/* Target Six v1.25 — brighter, tactile mathematical play. */
:root{--sky:#123d5d;--sky-deep:#092941;--board:#17435d;--board-light:#20536c;--ink:#fffaf0;--muted:#b9cfda;--line:#5a7f91;--cyan:#65e1db;--blue:#63b8ef;--cream:#fff7e5;--cream-2:#e8f3f1;--gold:#f4c96b;--green:#6fe0b5;--red:#ff9b9b}
body{min-height:100vh;color:var(--ink);background:radial-gradient(ellipse at 50% 39%,#3d7895 0,#255a75 18%,transparent 48%),radial-gradient(circle at 12% 18%,#2b7592 0,transparent 31rem),radial-gradient(circle at 88% 14%,#65568a55 0,transparent 30rem),linear-gradient(180deg,#164766 0,#0d3450 48%,#08243a 100%)}
body::before{content:"";position:fixed;z-index:-1;inset:0;pointer-events:none;opacity:.2;background-image:radial-gradient(circle,#d8f4ff 0 1px,transparent 1.4px),radial-gradient(circle,#ffe6a8 0 1px,transparent 1.3px);background-position:0 0,31px 27px;background-size:74px 74px,113px 113px;animation:sky-drift 28s linear infinite}body::after{content:"+   ×   ÷   −";position:fixed;z-index:-1;right:4vw;top:27vh;color:#d8f6ff0d;font:600 clamp(40px,7vw,94px)/1 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:2.4vw;transform:rotate(-8deg);pointer-events:none}
.game-skip{position:fixed;top:10px;left:10px;z-index:100;padding:11px 14px;border-radius:7px;background:var(--cream);color:#102f42;transform:translateY(-150%)}.game-skip:focus{transform:none}
.site-header{position:relative;top:0;width:min(1120px,calc(100% - 40px));min-height:70px;height:auto;margin:0 auto;padding:12px 0;border:0;border-bottom:1px solid #d9f2ff38;border-radius:0;background:transparent;box-shadow:none;backdrop-filter:none;color:#edf9ff}.brand-mark{border:1px solid #dff7ff3b;border-radius:10px 4px 10px 4px;background:#d7f5ff18;box-shadow:inset 0 1px #ffffff24}.brand strong{color:#fffdf6;font-weight:700}.brand small{color:#b8d4df;font-size:10px}.game-nav{display:flex;align-items:center;gap:25px;color:#c8dde6;font-size:13px}.game-nav>a{min-height:44px;display:inline-flex;align-items:center}.game-nav a:hover,.how-link:hover{color:#fff}.how-link{min-height:44px;padding:0;border:0;background:transparent;color:#c8dde6;font-size:13px}.how-link span{border:1px solid #8fd9de;border-radius:50%;background:#e2ffff12;color:#b7ffff}
.intro{max-width:1120px;padding:24px 20px 21px;text-align:left}.intro::before{display:none}.intro .eyebrow{margin-bottom:8px;color:#9ff6ea;font-size:11px;font-weight:700;letter-spacing:1.4px}.intro h1{color:#fffdf7;font-size:clamp(38px,4.3vw,54px);font-weight:630;letter-spacing:-2.8px;line-height:.98}.intro h1 span{margin-left:.16em;color:#a9f0eb}.intro>p:last-child{max-width:620px;margin:11px 0 0;color:#c5dce4;font-size:14px;line-height:1.5}
.game-shell{width:min(1120px,calc(100% - 40px));margin:0 auto 48px;overflow:hidden;border:1px solid #a7d5e46b;border-radius:18px 7px 18px 7px;background:#17435d;box-shadow:0 32px 80px #041b2d70,0 1px #d7f5ff2e inset}.setup-panel{padding:15px 20px;grid-template-columns:215px 1fr;gap:22px;border-bottom:1px solid #9fc9d54a;background:#24546b}
.panel-heading{display:grid;align-content:center;gap:8px}.panel-heading h2{margin:0 0 3px;color:#fffdf6;font-size:16px;font-weight:700;letter-spacing:-.25px}.panel-heading p{color:#b8d1db;font-size:11px}.daily-entry{display:grid;grid-template-columns:23px auto;grid-template-rows:auto auto;align-items:center;column-gap:7px;width:100%;min-width:0;padding:7px 9px;border:1px solid #f2ce7d73;border-radius:9px 3px 9px 3px;background:#fff2c714;color:#fff6d8;text-align:left}.daily-entry>span{grid-row:1/3;color:var(--gold);font-size:18px}.daily-entry strong{font-size:10px;line-height:1.1}.daily-entry small{color:#ddcfa6;font-size:8px;line-height:1.2}.daily-entry:hover:not(:disabled){transform:translateY(-1px);background:#fff1c522}.daily-entry.complete>span{color:var(--green)}
.setup-controls{grid-template-columns:minmax(280px,1.2fr) minmax(220px,.9fr) minmax(145px,.58fr);gap:15px}.control-label,.mix-label{margin-bottom:6px;color:#d2e1e6;font-size:11px;font-weight:700}.mix-label span{color:#9beae4;font-size:10px}.mode-control,.segment-control{padding:3px;border:1px solid #9fc1cc59;border-radius:9px 4px 9px 4px;background:#10374e}.mode-control button,.segment-control button{border-radius:6px 2px 6px 2px;color:#b4ccd6}.mode-control button{min-height:43px;padding:6px 9px}.mode-control strong{font-size:13px;font-weight:700}.mode-control small{font-size:9px}.mode-control button:hover:not(:disabled),.segment-control button:hover:not(:disabled){background:#2c6078;color:#fff}.mode-control button.selected{background:#e8f5f2;color:#16394c;box-shadow:0 2px 0 #bddedb}.segment-control button{min-height:43px;font-size:12px}.segment-control button.selected{background:#8de4de;color:#123849;box-shadow:0 2px 0 #54aaa7}.primary-button{min-height:49px;border:1px solid #96e9e4;border-radius:9px 3px 9px 3px;background:#73ddd5;color:#11384a;box-shadow:0 4px 0 #328e91;font-size:12px;font-weight:800}.primary-button:hover:not(:disabled){transform:translateY(-1px);background:#91ebe4;box-shadow:0 5px 0 #328e91}.primary-button:active:not(:disabled){transform:translateY(2px);box-shadow:0 2px 0 #328e91}.primary-button:disabled{background:#72929f;color:#dce7e8;box-shadow:0 3px 0 #4b7180}
.play-panel{position:relative;padding:18px 30px 30px;display:grid;grid-template-columns:225px minmax(0,1fr);gap:0 32px;background:radial-gradient(ellipse at 62% 35%,#4d8297 0,#2c627a 26%,transparent 67%),linear-gradient(105deg,#1a4861,#214f67 54%,#174158)}.play-panel::before{content:"";position:absolute;inset:54px 20px 15px 245px;pointer-events:none;background:radial-gradient(ellipse,#c4f6ee18 0,transparent 69%)}
.game-topbar,.timer-track{grid-column:1/-1;position:relative;z-index:1}.game-topbar{min-height:36px}.round-status{color:#d0e1e7;font-size:12px}.status-dot{background:#9bb4bd;box-shadow:0 0 0 4px #e8f6f522}.round-status.playing .status-dot{background:#83eee0;box-shadow:0 0 0 4px #68e5d82e}.round-status.finished .status-dot{background:var(--gold);box-shadow:0 0 0 4px #f4c96b2e}.session-stats{color:#a9c3cd;font-size:9px}.session-stats span+span{border-color:#b4d2dc40}.session-stats strong{color:#fff7e7;font-size:12px}.timer{color:#bad0d8}.timer strong{color:#fffaf1;font-size:24px}.timer-track{height:2px;margin-top:11px;border-radius:2px;background:#0c30454f}.timer-track i{background:#86e6dd}
.target-area{position:relative;z-index:1;min-height:0;height:100%;margin:19px 0 0;padding:24px 14px;align-content:start;border:0;border-right:1px solid #b0d7df45;border-radius:0;background:transparent;color:#fff}.target-area::before{inset:15px 20px auto;width:138px;height:138px;margin:auto;border:1px solid #bceef26b;border-radius:50%;background:radial-gradient(circle,#d6fff45c 0,#69dacf24 42%,transparent 70%);box-shadow:0 0 45px #8de8dc24;mask-image:none}.target-meta{justify-content:center}.target-meta span{color:#c4dce4;font-size:10px;font-weight:700}.target-meta em{padding:3px 7px;border:1px solid #eacb7b75;border-radius:8px 3px 8px 3px;background:#f3cf7b14;color:#ffe5a2;font-size:8px}.target-area>strong{margin-top:23px;color:#fffdf7;font:700 66px/1 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:-5px;text-shadow:0 2px 0 #3c6d7c,0 0 24px #a7fff053}.target-prompt{max-width:155px;margin-top:22px;color:#b8d1da;text-align:center}.pre-round .target-area>strong{margin-top:33px;color:#95b6c2;font-size:24px;letter-spacing:3px}.target-preview{display:none}
.answer-area{position:relative;z-index:1;min-width:0;padding:20px 0 0;border:0}.values-heading{align-items:end}.values-heading p{color:#b5ced7;font-size:12px}.builder-kicker{color:#9ff2e9;font-size:10px;font-weight:750;letter-spacing:.8px;text-transform:none}.round-progress{padding:0;border:0;border-radius:0;background:transparent}.round-progress strong{color:#b8cfd7;font-size:10px;font-weight:650}.round-progress span{background:#bddde26b}.working-values{min-height:88px;margin-top:13px;padding:0;grid-template-columns:repeat(6,minmax(0,1fr));gap:11px;border:0;border-radius:0;background:transparent}.working-values:empty::before{color:#a9c2cc}
.working-tile{position:relative;min-height:80px;padding:11px 5px 9px;border:1px solid #fffdf1;border-bottom:5px solid #9ebfbe;border-radius:15px 5px 15px 5px;background:linear-gradient(145deg,#fffdf4,#dcebea);color:#17384a;box-shadow:0 10px 17px #08263b42,0 1px #fff inset;transition:transform .14s ease,border-color .14s,background .14s,box-shadow .14s,opacity .14s}.working-tile::before{content:"";position:absolute;left:8px;top:8px;width:10px;height:3px;border-radius:2px;background:#83c8ce66}.working-tile strong{font:750 25px/1 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:-1px}.working-tile small{margin-top:8px;color:#65808d;font-size:8px;font-weight:700}.working-tile.original.small-number,.working-tile.original.large-number{border-color:#fffdf1;background:linear-gradient(145deg,#fffdf4,#dcebea);color:#17384a}.working-tile.original.large-number{background:linear-gradient(145deg,#fff9e9,#eadfc5);border-bottom-color:#c0a76d}.working-tile.original.small-number small,.working-tile.original.large-number small{color:#65808d}.working-tile.original.large-number::after{content:"";position:absolute;right:8px;top:8px;width:6px;height:6px;border-radius:50%;background:#d4a744}.working-tile.result{border-color:#bafff4;border-bottom-color:#359d99;background:linear-gradient(145deg,#e0fff8,#a5e5dd);color:#104d55}.working-tile.result small{color:#3e777c}.working-tile:hover:not(:disabled){transform:translateY(-4px) rotate(-.45deg);border-color:#fff;box-shadow:0 15px 21px #08263b54,0 1px #fff inset}.working-tile:nth-child(even):hover:not(:disabled){transform:translateY(-4px) rotate(.45deg)}.working-tile.selected{transform:translateY(-5px) scale(1.025);border-color:#fff9d7;box-shadow:0 0 0 3px #75e3da,0 16px 23px #08263b5e}.working-tile:disabled{opacity:.52;filter:saturate(.7)}.working-tile.is-new{animation:tile-result-in .31s cubic-bezier(.2,.85,.24,1) both}.working-tile.merge-left{animation:merge-left .28s ease-in both}.working-tile.merge-right{animation:merge-right .28s ease-in both}.working-values.undoing{animation:undo-reveal .23s ease-out}.working-values.invalid-shake{animation:invalid-shake .27s ease}
.builder-heading{margin-top:19px}.builder-heading h3{margin-top:3px;color:#fffaf0;font-size:16px;font-weight:650}.operator-row{margin-top:9px;grid-template-columns:repeat(4,48px);gap:8px}.operator-row button{height:44px;border:1px solid #a7cbd56e;border-bottom:3px solid #2c596c;border-radius:11px 3px 11px 3px;background:#2a5d74;color:#effbfc;font:700 19px/1 ui-monospace,SFMono-Regular,Menlo,monospace;box-shadow:0 4px 9px #09273a2b;transition:transform .13s,background .13s,border-color .13s}.operator-row button:hover:not(:disabled){transform:translateY(-2px);border-color:#d9ffff;color:#fff}.operator-row button.selected{transform:translateY(-2px);border-color:#fff0bc;background:#f2cf7b;color:#173a49;box-shadow:0 3px 0 #9b7942}.operator-row button:disabled{border-color:#7294a14a;border-bottom-color:#315a6a;background:#1d4960;color:#7799a6}
.player-steps{margin-top:14px;gap:0;border-top:1px solid #a8cbd54a}.player-steps li{min-height:35px;padding:7px 2px;gap:10px;border:0;border-bottom:1px solid #9fc4cf36;border-radius:0;background:transparent}.player-steps li>span{width:21px;height:21px;border-radius:7px 2px 7px 2px;background:#dff5f0;color:#195267;font-size:9px}.player-steps li strong{color:#edf8f7;font:650 13px/1.3 ui-monospace,SFMono-Regular,Menlo,monospace}.player-steps .empty-step{min-height:40px;border:0;border-bottom:1px solid #9fc4cf36;background:transparent;color:#aac3cc}.previous-solutions{margin-top:11px;border-top:1px solid #b5d5dc3d;color:#d9eaee}.previous-solutions summary{padding:9px 1px;cursor:pointer;color:#c4dae1;font-size:10px;font-weight:700}.previous-solutions summary span{display:inline-grid;place-items:center;width:18px;height:18px;margin-left:5px;border-radius:50%;background:#f2d47b;color:#183c4c}.previous-solutions section{display:grid;grid-template-columns:74px 1fr;gap:8px;padding:8px 0;border-top:1px solid #abcbd333}.previous-solutions section>strong{color:#efd993;font-size:9px}.previous-solutions ol{display:flex;flex-wrap:wrap;gap:5px}.previous-solutions li{color:#e2f0f2;font:600 10px/1.35 ui-monospace,SFMono-Regular,Menlo,monospace}
.edit-row{margin-top:12px}.edit-row button{min-width:0;min-height:39px;padding:0 13px;border:1px solid #a8cad563;border-radius:8px 3px 8px 3px;background:#214f66;color:#d8e8ed;font-size:11px;font-weight:700}.edit-row button:hover:not(:disabled){transform:translateY(-1px);border-color:#d7f7f7;color:#fff}.edit-row button:nth-child(3){border-color:#e8ce836e;color:#ffe9a8}.answer-actions{margin-top:10px;grid-template-columns:1fr}.answer-actions.can-submit{grid-template-columns:1fr 1fr}.answer-actions button,.result-actions button{min-height:44px;border-radius:9px 3px 9px 3px;font-size:11px;font-weight:750}.check-button,.play-again-button{background:#79ded6;color:#14394a;box-shadow:0 3px 0 #348f91}.solution-button,.retry-button,.share-button,.try-another-button{border:1px solid #afd0d868;background:#1d4b63;color:#dcebed}.try-another-button{border-color:#f1d6878a;color:#ffedb0}.feedback{min-height:40px;margin-top:10px;padding:6px 0;gap:9px;border:0!important;border-radius:0;background:transparent!important;color:#b8cfd7!important;font-size:11px}.feedback-icon{width:22px;height:22px;border-radius:8px 2px 8px 2px;background:#d9efed1c!important;color:#d8eced!important}.feedback.success{color:#aff3d6!important}.feedback.error{color:#ffd0d0!important}.feedback.solution{color:#ffe9a8!important}.feedback.solution .feedback-icon{color:#f4cf71!important}
.results-panel{margin:0;padding:2px 0 0;border:0;border-radius:0;background:transparent}.results-heading{padding:18px 0 15px;border-bottom:1px solid #b4d3da47;border-radius:0;background:transparent!important;color:#fffaf0!important}.results-heading span,.solution-steps>span,.result-player-steps>span{color:#b2cbd4!important;font-size:9px;font-weight:700}.results-heading h3{margin-top:5px;font-size:26px;font-weight:700;letter-spacing:-.8px}.results-heading>strong{padding:0;background:transparent!important;color:#ffe191!important;font-size:28px}.result-player-steps{margin-top:14px}.result-player-steps ol{margin-top:8px;grid-template-columns:1fr;gap:0;border-top:1px solid #a5c7cf47}.result-player-steps li{min-height:33px;padding:6px 1px;border:0;border-bottom:1px solid #a5c7cf38;border-radius:0;background:transparent}.result-player-steps li strong{color:#edf6f5;font:650 13px/1.3 ui-monospace,SFMono-Regular,Menlo,monospace}.step-number{color:#ffe397;font-size:16px}.result-grid{margin-top:14px;grid-template-columns:repeat(4,1fr);border:1px solid #b5d2d94a;border-radius:10px 3px 10px 3px;background:#123d55}.result-grid>div{padding:10px 12px}.result-grid>div+div{border-color:#aacbd44a}.result-grid span{color:#adc7d0;font-size:9px}.result-grid strong{color:#fff9ed;font-size:13px}.solution-steps{margin-top:14px;padding-top:12px;border-color:#a9c9d24a}.solution-steps ol{margin-top:8px;gap:0;border-top:1px solid #a5c7cf47}.solution-steps li{min-height:42px;padding:7px 1px;border:0;border-bottom:1px solid #a5c7cf38;border-radius:0;background:transparent}.solution-steps li strong{color:#e5f2f3;font:650 13px/1.3 ui-monospace,SFMono-Regular,Menlo,monospace}.solution-steps li small{color:#abc4cd;font-size:9px}.exact-result .solution-steps{display:none}.result-invitation{margin:15px 0 0;color:#ffe29a;font-size:13px;font-weight:650}.result-actions{margin-top:12px;grid-template-columns:1.35fr 1fr 1fr 1fr;gap:8px}.share-button:hover:not(:disabled),.retry-button:hover:not(:disabled),.try-another-button:hover:not(:disabled){border-color:#d9f4f4;color:#fff}
.success-burst{position:absolute;z-index:8;left:8%;top:12%;width:170px;height:170px;border-radius:50%;opacity:0;pointer-events:none;background:radial-gradient(circle,#fff8d7 0 4%,#ffe18d9c 5%,#76ebd769 25%,transparent 67%)}.success-burst::before,.success-burst::after{content:"✦";position:absolute;inset:-22%;display:grid;place-items:start end;color:#ffe899;font-size:23px;border:1px solid #befff0b0;border-radius:50%}.success-burst::after{content:"·  ✦  ·";inset:-53%;place-items:end start;border-color:#ffd87970;font-size:17px}.celebrating .success-burst{animation:success-burst .98s ease-out}.celebrating .target-area>strong{animation:target-win .98s ease-out}.celebrating .target-area{filter:brightness(1.13)}.celebrating .working-tile{animation:piece-cheer .72s ease-out}
.countdown-overlay{border-radius:0;background:#123d55e8;backdrop-filter:blur(3px)}.countdown-overlay strong{font-size:96px;font-weight:650;color:#fff8e7}.rules{width:min(1120px,calc(100% - 40px));margin-bottom:45px;padding:27px 30px;border:1px solid #a4c9d44d;border-radius:14px 5px 14px 5px;background:#153d54;box-shadow:0 20px 48px #071e2e38}.rules .eyebrow{color:#9ae9e2}.rules h2{font-weight:620}.rule-flow>div{border-color:#96bdc85c;border-radius:10px 3px 10px 3px;background:#1d4a61}.rule-note{color:#b5cdd5}.tutorial-dialog{border-radius:14px 5px 14px 5px}.tutorial-card{border-color:#80a9b87a;border-radius:14px 5px 14px 5px;background:#19465e;color:#edf8f8}.tutorial-card h2{color:#fff9ed;font-weight:650}.tutorial-card>p:not(.eyebrow),.tutorial-card ol{color:#c0d6dd}.dialog-close{border-color:#9fc2cd65;border-radius:8px 3px 8px 3px;background:#28576d;color:#e1eff1}.tutorial-example{border-radius:11px 4px 11px 4px;background:#10394f}.tutorial-example span,.tutorial-example strong{border-radius:9px 3px 9px 3px;background:#eaf3ee;color:#173b4b}.tutorial-example strong{background:#b9f0df;color:#174e50}.secondary-button{border-color:#a8cbd465;border-radius:8px 3px 8px 3px;background:#1b4960;color:#e2eff1}footer{border-top:1px solid #a0c3ce45;background:#08263b59;color:#aac4cd}footer .brand strong{color:#ecf6f5}
@keyframes sky-drift{to{background-position:24px 8px,5px 45px}}@keyframes tile-result-in{0%{opacity:0;transform:scale(.7) rotate(-3deg)}65%{opacity:1;transform:scale(1.07) rotate(1deg)}100%{transform:scale(1)}}@keyframes merge-left{to{opacity:0;transform:translateX(34%) scale(.78) rotate(2deg)}}@keyframes merge-right{to{opacity:0;transform:translateX(-34%) scale(.78) rotate(-2deg)}}@keyframes undo-reveal{from{opacity:.45;transform:translateY(5px) scale(.98)}to{opacity:1;transform:none}}@keyframes invalid-shake{25%{transform:translateX(-4px) rotate(-.3deg)}50%{transform:translateX(3px) rotate(.3deg)}75%{transform:translateX(-2px)}}@keyframes success-burst{0%{opacity:0;transform:scale(.3) rotate(-10deg)}22%{opacity:1}100%{opacity:0;transform:scale(1.7) rotate(12deg)}}@keyframes target-win{0%,100%{transform:scale(1)}30%{transform:scale(1.14);text-shadow:0 2px 0 #907233,0 0 42px #fff0a2}62%{transform:scale(1.035)}}@keyframes piece-cheer{0%,100%{transform:none}36%{transform:translateY(-8px) rotate(-1deg)}66%{transform:translateY(-2px) rotate(1deg)}}
@media(max-width:980px){.setup-panel{grid-template-columns:1fr}.panel-heading{align-items:flex-start}.daily-entry{max-width:210px}.setup-controls{grid-template-columns:1fr 1fr}.primary-button{grid-column:1/-1}.play-panel{grid-template-columns:185px minmax(0,1fr);padding-inline:22px}.working-tile small{display:none}.result-actions{grid-template-columns:1fr 1fr}}
@media(max-width:720px){body{background:radial-gradient(circle at 50% 26%,#39748e 0,transparent 23rem),linear-gradient(180deg,#174a69,#0b2c46)}body::after{display:none}.site-header{width:calc(100% - 28px);min-height:62px;padding:9px 0}.game-nav{gap:15px;font-size:12px}.how-link{font-size:12px}.how-link span{display:none}.brand small{font-size:9px}.intro{padding:23px 18px 21px}.intro h1{font-size:37px;letter-spacing:-2px}.intro h1 span{display:block;margin-left:0}.intro>p:last-child{font-size:13px}.game-shell{width:calc(100% - 16px);border-radius:14px 5px 14px 5px}.setup-panel{padding:14px}.panel-heading{display:flex;align-items:center}.daily-entry{width:auto;max-width:190px}.setup-controls{display:block}.mix-control{margin-top:12px}.mode-control button{min-height:50px}.segment-control button{min-height:46px}.primary-button{margin-top:12px}.play-panel{display:block;min-height:0;padding:14px;background:radial-gradient(ellipse at 50% 25%,#4f879b 0,transparent 24rem),#1d4b63}.play-panel::before{display:none}.target-area{height:auto;min-height:126px;margin:10px 0 18px;padding:13px;border-right:0;border-bottom:1px solid #b5d5dc47}.target-area::before{top:0;width:122px;height:122px}.target-area>strong{margin-top:12px;font-size:58px}.pre-round .target-area>strong{margin-top:18px}.answer-area{padding-top:0}.values-heading{align-items:flex-start}.round-progress{width:auto}.working-values{grid-template-columns:repeat(3,minmax(0,1fr));gap:9px}.working-tile{min-height:68px}.working-tile strong{font-size:23px}.working-tile small{display:block;font-size:8px}.operator-row{grid-template-columns:repeat(4,1fr);gap:8px}.operator-row button{height:50px}.edit-row{display:grid;grid-template-columns:repeat(2,1fr);gap:8px}.edit-row button{padding:0 6px;min-height:46px}.answer-actions button{min-height:49px}.previous-solutions section{grid-template-columns:1fr}.results-panel{margin:0;padding:0 0 12px}.result-grid{grid-template-columns:repeat(2,1fr)}.result-grid>div:nth-child(3){border-top:1px solid #aacbd44a;border-left:0}.result-grid>div:nth-child(4){border-top:1px solid #aacbd44a}.result-actions{grid-template-columns:1fr 1fr}.result-actions button{min-height:49px}.success-burst{left:calc(50% - 85px);top:55px}.rules{width:calc(100% - 20px);padding:25px 18px}.rule-flow>div{min-height:62px}.tutorial-card{padding:25px 18px}.round-running .game-skip,.round-preparing .game-skip,.results-visible .game-skip{display:none}}
@media(max-width:420px){.panel-heading{display:block}.daily-entry{width:100%;max-width:none;margin-top:10px}.session-stats{gap:7px}.session-stats span{padding:0 7px}.working-values{gap:7px}.working-tile{min-width:0}.result-actions{grid-template-columns:1fr}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}

/* v1.25 puzzle-table refinement */
.round-summary{display:none;align-items:center;justify-content:space-between;gap:18px;min-height:38px}.round-summary strong{color:#eaf7f3;font-size:11px;letter-spacing:.02em}.round-summary button{min-height:32px;padding:0 11px;border:1px solid #a9cbd464;border-radius:16px;background:transparent;color:#d4e6eb;font-size:10px;font-weight:700}.round-summary button:hover{border-color:#e2f6f7;color:#fff}
.round-preparing .intro,.round-running .intro,.results-visible .intro{display:none}.round-preparing .rules,.round-running .rules,.results-visible .rules{display:none}.round-preparing .game-shell,.round-running .game-shell,.results-visible .game-shell{margin-top:18px}.round-preparing .setup-panel,.round-running .setup-panel,.results-visible .setup-panel{display:block;padding:7px 20px;background:#153d53}.round-preparing .setup-panel>.panel-heading,.round-preparing .setup-controls,.round-running .setup-panel>.panel-heading,.round-running .setup-controls,.results-visible .setup-panel>.panel-heading,.results-visible .setup-controls{display:none}.round-preparing .round-summary,.round-running .round-summary,.results-visible .round-summary{display:flex}
.play-panel{display:block;padding:17px 30px 30px;background:radial-gradient(ellipse at 50% 38%,#568ba0 0,#32677e 28%,#1a4961 72%)}.play-panel::before{inset:48px 8% 20px;background:radial-gradient(ellipse at 50% 32%,#f6e6bc18 0,#b8fff11a 28%,transparent 69%)}
.target-area{width:100%;height:auto;min-height:160px;margin:10px 0 0;padding:18px 0 10px;border:0;border-bottom:1px solid #b5d8df35;place-items:center;text-align:center}.target-area::before{inset:5px 0 auto;width:142px;height:142px;background:radial-gradient(circle,#d6fff45c 0,#69dacf20 43%,transparent 70%);transition:filter .25s,transform .25s,box-shadow .25s}.target-meta{width:auto;gap:9px;justify-content:center}.target-area>strong{margin-top:12px;font-size:64px}.target-prompt{display:none!important}.distance-readout{position:relative;z-index:1;min-height:18px;margin-top:8px;color:#d8e8e8;font-size:11px;font-weight:650;letter-spacing:.01em}.target-area.distance-near::before{filter:brightness(1.12);box-shadow:0 0 46px #88e7d63d}.target-area.distance-hot::before{filter:brightness(1.25);box-shadow:0 0 58px #a7f4df68;animation:target-breathe 1.6s ease-in-out infinite}.target-area.distance-exact::before{filter:brightness(1.35);box-shadow:0 0 66px #baffdf88}
.answer-area{max-width:950px;margin:0 auto;padding:15px 0 0}.values-heading{margin-bottom:0}.values-heading p{display:none}.working-values{min-height:90px;margin-top:10px;gap:13px}.working-tile{min-height:86px;border-radius:20px 7px 18px 6px;box-shadow:0 12px 0 #12394b45,0 17px 25px #092b3f42,0 1px #fff inset}.working-tile::before{width:13px;height:3px;background:#6099a477}.working-tile strong{font-size:28px}.working-tile:hover:not(:disabled){transform:translateY(-5px) rotate(-.6deg);box-shadow:0 15px 0 #12394b38,0 22px 28px #092b3f55,0 1px #fff inset}.working-tile:nth-child(even):hover:not(:disabled){transform:translateY(-5px) rotate(.6deg)}.working-tile.selected{transform:translateY(-7px) scale(1.035);box-shadow:0 0 0 3px #64ddd3,0 16px 0 #12394b33,0 23px 30px #092b3f59}.used-slot{position:relative;min-height:86px;border:1px dashed #bee0e43b;border-radius:20px 7px 18px 6px;background:#153f5550}.used-slot i{position:absolute;left:50%;top:50%;width:16px;height:2px;border-radius:2px;background:#bad5da52;transform:translate(-50%,-50%) rotate(-18deg)}
.calculation-stage{display:flex;align-items:center;justify-content:center;gap:12px;min-height:62px;margin-top:18px;border-top:1px solid #bddce243;border-bottom:1px solid #bddce243;color:#a9c8d1;font:700 22px/1 ui-monospace,SFMono-Regular,Menlo,monospace}.calculation-stage span,.calculation-stage strong{min-width:42px;text-align:center}.calculation-stage b{display:grid;place-items:center;width:34px;height:34px;border-radius:50%;background:#173f56;color:#d8eef0}.calculation-stage i{color:#8fb4bf;font-style:normal}.calculation-stage.has-values{color:#fff8e7}.calculation-stage.has-values b{background:#f3ce77;color:#183a49}.calculation-stage.landed strong{color:#91f0d9;animation:calculation-impact .34s cubic-bezier(.2,.8,.2,1)}.calculation-stage.merging span{animation:calculation-inward .28s ease-in both}.builder-instruction{min-height:17px;margin-top:7px;color:#d6e7e9;text-align:center;font-size:11px}.operator-row{width:max-content;margin:9px auto 0;padding:5px;grid-template-columns:repeat(4,48px);gap:5px;border:1px solid #a9cbd45c;border-radius:24px;background:#173f56;box-shadow:0 8px 20px #0b2b3e42}.operator-row button{height:40px;border:0;border-bottom:2px solid transparent;border-radius:50%;background:transparent;box-shadow:none}.operator-row button:hover:not(:disabled){transform:translateY(-2px);background:#2e6378}.operator-row button.selected{transform:translateY(-2px);border:0;border-bottom:2px solid #a27936;background:#f2cf7b;color:#173a49;box-shadow:0 4px 0 #9b7942}.operator-row button:disabled{border:0;background:transparent;color:#7295a2;box-shadow:none}
.math-trail{display:grid;grid-template-columns:105px 1fr;gap:15px;margin-top:15px;padding-top:12px;border-top:1px solid #b2d1d83d}.math-trail>div small{display:block;margin-top:3px;color:#a9c3cc;font-size:9px}.player-steps{position:relative;margin:0;border:0}.player-steps::before{content:"";position:absolute;left:10px;top:13px;bottom:13px;width:1px;background:#82cfc870}.player-steps li{position:relative;z-index:1;min-height:32px;padding:4px 0;gap:10px;border:0;background:transparent}.player-steps li>span{border:1px solid #9de5dd;background:#24576c;color:#dffffb}.player-steps li strong{font-size:12px}.player-steps li strong i{color:#f2d582;font-style:normal}.player-steps .empty-step{min-height:28px;padding-top:5px;border:0;color:#aac6ce;font-size:10px}.player-steps .empty-step::before{content:"";width:7px;height:7px;margin:0 7px;border-radius:50%;background:#8dc9c5}.edit-row{justify-content:center;margin-top:13px}.edit-row button{background:#1a455b}.edit-row #hint-button{border-color:#f2d27b8c;color:#ffebad}.edit-row #hint-button::before{content:"✦";margin-right:5px;color:#f3cf72}.feedback{max-width:650px;margin:8px auto 0;justify-content:center;text-align:center}.answer-actions{max-width:620px;margin-inline:auto}
.mode-practice .timer,.mode-daily .timer{opacity:.38}.mode-practice .timer-track,.mode-daily .timer-track{opacity:.3}.mode-challenge .timer strong{font-size:18px;letter-spacing:.03em}
.results-visible .values-heading{display:flex}.results-visible .working-values{display:grid}.results-visible .math-trail,.results-visible .player-steps{display:grid}.results-visible .calculation-stage,.results-visible .builder-instruction,.results-visible .answer-area>.operator-row,.results-visible .edit-row,.results-visible .answer-actions,.results-visible .feedback{display:none}.results-panel{max-width:760px;margin:18px auto 0;padding:18px 22px;border-top:1px solid #f0d98d78;background:#153f5655}.exact-result .result-player-steps{display:none}.results-heading{padding-top:0}.result-actions{grid-template-columns:1.35fr 1fr 1fr 1fr}.try-another-button{background:#f0d078;color:#173b4b;font-weight:800}
@keyframes target-breathe{50%{transform:scale(1.025)}}@keyframes calculation-inward{50%{transform:translateX(8px);filter:brightness(1.2)}100%{transform:none}}@keyframes calculation-impact{0%{opacity:0;transform:scale(.65)}65%{opacity:1;transform:scale(1.12)}100%{transform:scale(1)}}
@media(max-width:720px){.round-preparing .site-header,.round-running .site-header,.results-visible .site-header{display:none}.round-preparing .setup-panel,.round-running .setup-panel,.results-visible .setup-panel{display:block!important}.round-preparing .game-shell,.round-running .game-shell,.results-visible .game-shell{width:100%;margin:0;border:0}.round-summary{min-height:40px}.play-panel{padding:12px 14px 22px}.target-area{min-height:133px;margin-top:5px;padding-top:11px}.target-area::before{width:122px;height:122px}.target-area>strong{font-size:57px}.answer-area{padding-top:10px}.working-values{grid-template-columns:repeat(3,minmax(0,1fr));gap:9px}.working-tile,.used-slot{min-height:70px}.working-tile strong{font-size:24px}.calculation-stage{min-height:57px;margin-top:14px;font-size:19px}.operator-row{width:100%;grid-template-columns:repeat(4,1fr)}.operator-row button{height:45px}.math-trail{grid-template-columns:1fr;gap:6px}.math-trail>div{display:flex;align-items:center;justify-content:space-between}.edit-row{grid-template-columns:repeat(4,1fr);gap:6px}.edit-row button{min-height:44px;font-size:10px}.result-actions{grid-template-columns:1fr 1fr}.results-panel{padding-inline:8px}.results-visible .working-values{display:grid}}
@media(max-width:440px){.edit-row{grid-template-columns:repeat(2,1fr)}.result-actions{grid-template-columns:1fr}.round-summary strong{font-size:10px}}
@media(prefers-reduced-motion:reduce){.target-area.distance-hot::before{animation:none}}

/* v1.26 premium game feel — quieter structure, stronger play materials. */
:root{--sky:#213244;--sky-deep:#101d2b;--board:#354c5e;--board-light:#496274;--muted:#c2ced3;--line:#7e929e;--cyan:#69d7d0;--blue:#79acd3;--cream:#fff7e7;--cream-2:#ebe5d8;--gold:#e9c575;--green:#79d9aa;--red:#f09a9a}
body{background:radial-gradient(ellipse at 50% 38%,#617486 0,#3e5365 21%,transparent 50%),radial-gradient(circle at 12% 18%,#476477 0,transparent 31rem),radial-gradient(circle at 88% 14%,#675e7655 0,transparent 30rem),linear-gradient(180deg,#344b5f 0,#22384b 48%,#101f30 100%)}
body::before{opacity:.15;background-image:radial-gradient(circle,#eef7f7 0 1px,transparent 1.35px),radial-gradient(circle,#f5dfad 0 1px,transparent 1.25px),linear-gradient(27deg,transparent 49.7%,#d9e4e70a 50%,transparent 50.3%);background-size:83px 83px,127px 127px,190px 190px}
body::after{color:#edf3f40b}
.game-shell{border-color:#c1cbd052;background:#334b5d;box-shadow:0 32px 80px #07131f78,0 1px #ffffff30 inset}
.setup-panel,.round-preparing .setup-panel,.round-running .setup-panel,.results-visible .setup-panel{background:#293e50;border-color:#8799a34f}
.round-motto{color:#aebdc4;font:500 10px/1.3 Georgia,serif;font-style:italic;letter-spacing:.02em}
.daily-entry{grid-template-columns:23px auto auto}.daily-entry>span:first-child{grid-row:1/3}.daily-five{display:flex;grid-column:3;grid-row:1/3;gap:3px;align-items:center;margin-left:auto}.daily-five i{width:5px;height:5px;border:1px solid #dfca9785;border-radius:50%;background:transparent}.daily-five i.complete{border-color:#78d6a7;background:#78d6a7;box-shadow:0 0 7px #78d6a770}
.play-panel{isolation:isolate;background:radial-gradient(ellipse at 50% 30%,#738491 0,#526a7a 27%,#344d60 68%,#293f52 100%)}
.play-panel::before{z-index:-1;inset:38px 7% 20px;background:radial-gradient(ellipse at 50% 25%,#fff3d51a 0,#dbe8e818 26%,transparent 68%),repeating-radial-gradient(circle at 50% 26%,transparent 0 76px,#ecf2f20c 77px 78px,transparent 79px 132px)}
.play-panel::after{content:"";position:absolute;z-index:-1;inset:82px 12% auto;height:260px;pointer-events:none;opacity:.28;background:linear-gradient(31deg,transparent 49.7%,#eef3f31c 50%,transparent 50.3%),linear-gradient(-31deg,transparent 49.7%,#eef3f312 50%,transparent 50.3%);background-size:118px 72px}
.game-topbar{border-color:#d8e0e02b}.round-status strong,.session-stats,.timer{color:#d9e1e2}.session-stats span{background:transparent;border-color:#c8d1d125}.session-stats span+span{border-left-color:#c8d1d125}
.target-area{overflow:visible;border-color:#d8dddc31}.target-area::before{background:radial-gradient(circle,#fff6dc33 0 20%,#cfe1df24 21% 42%,transparent 43% 51%,#dce7e719 52% 53%,transparent 54% 69%);border:1px solid #d7dfde36;box-shadow:inset 0 0 0 12px #d7e0df08;transition:filter .3s,transform .3s,box-shadow .3s,border-color .3s}
.target-area::after{content:"";position:absolute;z-index:0;top:0;width:154px;height:154px;border-radius:50%;opacity:.44;background:repeating-conic-gradient(from 0deg,#e7ecec80 0 1deg,transparent 1deg 15deg);-webkit-mask:radial-gradient(circle,transparent 0 70%,#000 71% 74%,transparent 75%);mask:radial-gradient(circle,transparent 0 70%,#000 71% 74%,transparent 75%);pointer-events:none}
.target-meta span,.target-meta em,.builder-kicker{text-transform:none;letter-spacing:.04em}.target-area>strong{color:#fff9e9;text-shadow:0 2px 0 #24313a,0 7px 20px #16243050}.distance-readout{color:#e0e5e4}.target-area.distance-warm::before{filter:brightness(1.07);border-color:#d8d0a05e;box-shadow:0 0 34px #e4cc7950}.target-area.distance-near::before{filter:brightness(1.13);border-color:#9fd6c56e;box-shadow:0 0 48px #79d5bd52}.target-area.distance-hot::before{filter:brightness(1.23);border-color:#8ce4bf9e;box-shadow:0 0 58px #7be1b06b;animation:target-breathe 1.6s ease-in-out infinite}.target-area.distance-exact::before{filter:brightness(1.33);border-color:#fff0adad;box-shadow:0 0 72px #8ee5bb88,0 0 24px #fff0b06e inset}
.working-tile{border-color:#d7d0c07c;background:radial-gradient(circle at 22% 18%,#ffffffde 0 4%,transparent 5%),radial-gradient(circle at 76% 72%,#aa9f8d29 0 3%,transparent 4%),linear-gradient(145deg,#fffaf0 0,#e9e3d6 44%,#d2c9b9 100%);color:#263947;box-shadow:0 12px 0 #22323e4d,0 18px 26px #1726335c,0 1px #fff inset}.working-tile::after{content:"";position:absolute;inset:5px;border:1px solid #77705f17;border-radius:16px 5px 15px 5px;pointer-events:none}.working-tile.result{background:radial-gradient(circle at 20% 18%,#ffffffa8 0 4%,transparent 5%),linear-gradient(145deg,#d9efe9,#b7dbd3 55%,#91c0b6);color:#173f46}.working-tile.large-number{background:radial-gradient(circle at 22% 18%,#ffffffc9 0 4%,transparent 5%),linear-gradient(145deg,#fff2cb,#e7d198 52%,#cdb879);color:#3e392b}.working-tile small{color:#5d676b}.working-tile.large-number small{color:#6f623e}.used-slot{border-color:#d5dcda37;background:#2c435352}
.calculation-stage{border-color:#d3dcdb38;color:#bdc8cb}.calculation-stage b,.operator-row{background:#293b4b}.calculation-stage.has-values b,.operator-row button.selected{background:#e9c879;color:#2a3942}.operator-row{border-color:#aebabe50;box-shadow:0 8px 20px #17263355}.operator-row button:hover:not(:disabled){background:#465d6d}.operator-row button:disabled{color:#778b95}
.math-trail{border-color:#d2dad936}.math-trail>div small,.player-steps .empty-step{color:#b9c5c8}.player-steps::before{background:#a7c8c06b}.player-steps li>span{border-color:#bdd9d2;background:#3d5966;color:#eff8f3}
.edit-row button{background:#344c5e;border-color:#aab6ba54;color:#dce3e4}.edit-row #hint-button{border-color:#e4ca7c75;color:#f6dda0}.solution-button{min-height:28px!important;width:max-content;margin:0 auto;padding:0 5px!important;border:0!important;border-bottom:1px solid #c7d0d270!important;border-radius:0!important;background:transparent!important;color:#c7d0d2!important;box-shadow:none!important;font-size:10px!important}.answer-actions.can-submit .solution-button{align-self:center}.feedback{color:#c5ced0!important}
.results-panel{background:linear-gradient(180deg,#2d435366,#263b4b30);border-color:#e5ca7f71}.results-heading{border-color:#ccd4d337}.results-heading span,.solution-steps>span,.result-player-steps>span{font-size:10px;text-transform:none;letter-spacing:.04em}.result-grid{display:flex;flex-wrap:wrap;gap:0;margin-top:15px;border:0;border-top:1px solid #cbd3d237;border-bottom:1px solid #cbd3d237;border-radius:0;background:transparent}.result-grid>div{flex:1;min-width:90px;padding:10px 12px}.result-grid>div+div{border-left:1px solid #cbd3d22f}.result-grid span{text-transform:none;letter-spacing:.02em}.result-achievements{display:flex;flex-wrap:wrap;gap:18px;margin-top:14px}.result-achievements[hidden]{display:none}.result-achievements>span{display:grid;grid-template-columns:18px auto;grid-template-rows:auto auto;column-gap:6px;align-items:center;color:#f1d98d}.result-achievements i{grid-row:1/3;font-style:normal}.result-achievements strong{font-size:11px}.result-achievements small{color:#bfc8ca;font-size:9px}.result-record{margin-top:10px;color:#f4d882;font:700 12px/1.3 Georgia,serif}.result-actions{grid-template-columns:1.5fr 1fr 1fr auto}.try-another-button{background:#eacb7b;color:#273942;box-shadow:0 3px 0 #987f49}.share-button{padding-inline:14px}.result-invitation{font-family:Georgia,serif;font-weight:600}
.celebrating .success-burst{animation:success-burst 1.15s ease-out}.celebrating .target-area>strong{animation:target-win 1.15s ease-out}.celebrating .working-tile{animation:piece-cheer .86s ease-out}.celebrating .working-tile.result{animation:result-lock 1.05s cubic-bezier(.2,.75,.2,1)}.merge-left{animation-duration:.34s}.merge-right{animation-duration:.34s}.undoing .working-tile{animation:undo-reveal .32s cubic-bezier(.2,.8,.2,1)}
@keyframes result-lock{0%,100%{transform:none}32%{transform:translateY(-18px) scale(.97);box-shadow:0 16px 30px #17263370,0 0 0 2px #92dfc5}62%{transform:translateY(-6px);box-shadow:0 13px 24px #1726335c,0 0 18px #92dfc550}}
@media(max-width:720px){body{background:radial-gradient(circle at 50% 25%,#5d7180 0,transparent 24rem),linear-gradient(180deg,#394f61,#15293b)}.play-panel{background:radial-gradient(ellipse at 50% 21%,#708390 0,#465f70 33%,#2c4355 100%)}.play-panel::after{display:none}.round-motto{display:none}.target-area::after{top:-1px;width:134px;height:134px}.daily-entry{grid-template-columns:23px auto auto}.result-grid{display:grid;grid-template-columns:repeat(2,1fr)}.result-grid>div:nth-child(3){border-left:0}.result-actions{grid-template-columns:1fr 1fr}.result-achievements{gap:12px}.result-achievements>span{min-width:calc(50% - 6px)}}
@media(max-width:440px){.result-actions{grid-template-columns:1fr}.result-achievements{display:grid}.result-achievements>span{min-width:0}}
@media(prefers-reduced-motion:reduce){.target-area.distance-hot::before{animation:none}.merge-left,.merge-right,.undoing .working-tile{animation:none!important}}

/* v1.29 retention and product polish — additions only; approved game layout retained. */
.sound-toggle{min-height:34px;padding:0 12px;border:1px solid #aebabe50;border-radius:18px;background:#293e50;color:#d9e2e3;font-size:10px;font-weight:750;letter-spacing:.02em}.sound-toggle:hover{border-color:#d8e0e0;color:#fff}.onboarding-coach{position:absolute;z-index:18;top:68px;left:50%;display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:10px;width:min(520px,calc(100% - 30px));min-height:52px;padding:9px 12px;border:1px solid #ebd0898c;border-radius:12px;background:#1d3447f2;box-shadow:0 14px 36px #0d1c2c72,0 0 22px #e7ca7250;transform:translateX(-50%);color:#f8f2df}.onboarding-coach[hidden]{display:none}.onboarding-coach>span{display:grid;place-items:center;min-width:42px;height:27px;border-radius:15px;background:#eacb7b;color:#293942;font-size:9px;font-weight:850}.onboarding-coach strong{font-size:12px}.onboarding-coach button{min-height:32px;padding:0 10px;border:0;border-bottom:1px solid #bdc9cb;background:transparent;color:#dbe4e5;font-size:10px}.progress-dialog{width:min(680px,calc(100% - 24px));border:1px solid #bdc8cb60;border-radius:18px;background:#263d50;color:#f5f7f5;box-shadow:0 28px 85px #07131fbf}.progress-dialog::backdrop{background:#07131fd1;backdrop-filter:blur(7px)}.progress-card{position:relative;padding:28px}.progress-card h2{margin:5px 0 20px;font:750 clamp(24px,4vw,36px)/1.05 system-ui,sans-serif}.progress-card .dialog-close{position:absolute;right:16px;top:14px}.progress-grid{display:grid;grid-template-columns:repeat(3,1fr);border:1px solid #bdc8cb42;border-radius:12px;overflow:hidden}.progress-grid>div{min-height:92px;padding:18px;border-right:1px solid #bdc8cb2e;border-bottom:1px solid #bdc8cb2e}.progress-grid>div:nth-child(3n){border-right:0}.progress-grid>div:nth-child(n+4){border-bottom:0}.progress-grid span{display:block;color:#bdc9cd;font-size:10px}.progress-grid strong{display:block;margin-top:8px;color:#fff4d5;font-size:21px}.progress-play{width:100%;margin-top:18px}.result-grid>div{min-width:84px}.results-panel[data-outcome="exact"] .result-routes{color:#8ee2bd}@media(max-width:720px){.game-nav{gap:7px}.sound-toggle{min-height:42px;padding:0 10px}.onboarding-coach{position:sticky;top:8px;margin:-4px auto 8px;transform:none}.progress-grid{grid-template-columns:repeat(2,1fr)}.progress-grid>div:nth-child(3n){border-right:1px solid #bdc8cb2e}.progress-grid>div:nth-child(2n){border-right:0}.progress-grid>div:nth-child(n+4){border-bottom:1px solid #bdc8cb2e}.progress-grid>div:nth-child(n+5){border-bottom:0}}@media(max-width:440px){.game-nav>a{display:none}.progress-card{padding:25px 16px}.progress-grid>div{min-height:80px;padding:14px}.progress-grid strong{font-size:17px}.onboarding-coach{grid-template-columns:auto 1fr}.onboarding-coach button{grid-column:2;justify-self:start}}

/* v1.30 game-feel polish. */
.working-tile:active:not(:disabled){transform:translateY(-1px) scale(.965)!important;box-shadow:0 6px 0 #22323e4d,0 9px 16px #1726334a,0 1px #fff inset}.working-tile.is-new{animation:stone-land-v130 .38s cubic-bezier(.18,.75,.2,1)}.round-refreshing .target-area>strong{animation:target-reveal-v130 .48s ease-out both}.round-refreshing .working-tile{animation:stones-enter-v130 .46s cubic-bezier(.18,.75,.2,1) both}.round-refreshing .working-tile:nth-child(2){animation-delay:.035s}.round-refreshing .working-tile:nth-child(3){animation-delay:.07s}.round-refreshing .working-tile:nth-child(4){animation-delay:.105s}.round-refreshing .working-tile:nth-child(5){animation-delay:.14s}.round-refreshing .working-tile:nth-child(6){animation-delay:.175s}.calculation-stage.merging b{animation:operator-compress-v130 .3s ease}.merge-left{filter:brightness(1.09)}.merge-right{filter:brightness(1.09)}.target-area.distance-near::after{animation:target-ring-drift-v130 4s linear infinite}.target-area.distance-hot::before{animation:target-breathe 1.15s ease-in-out infinite}.target-area.distance-almost::before{filter:brightness(1.32);border-color:#b1f3d8b8;box-shadow:0 0 70px #79e9bd83,0 0 20px #fff1b057 inset;animation:target-almost-v130 .78s ease-in-out infinite}.target-area.distance-almost::after{opacity:.8;animation:target-ring-drift-v130 1.8s linear infinite}.result-record{width:max-content;max-width:100%;padding:7px 11px;border:1px solid #efd78366;border-radius:16px;background:#d9b44e13;animation:record-reveal-v130 .5s ease-out}.result-daily-streak{margin-top:9px;color:#d8e2e2;font-size:11px}.result-daily-streak[hidden]{display:none}.alternate-route-found .results-panel{border-top-color:#8de2d2;box-shadow:0 -8px 32px #69d6ca1a}.alternate-route-found .results-heading h3{color:#f2d783}.alternate-route-found #result-points{color:#8fe2cf}.alternate-route-found .result-invitation{color:#f2da91}.daily-five.set-complete::after{content:"✓";margin-left:3px;color:#79d9aa;font-size:9px;font-weight:900}.result-actions #new-puzzle{order:1}.result-actions #try-another{order:2}.result-actions #share-result{order:3}.result-actions #retry-puzzle{order:4}.result-actions #new-puzzle{background:#eacb7b;color:#273942;box-shadow:0 3px 0 #987f49}.result-actions #try-another{background:#3f6675;color:#f5f7ef;box-shadow:none}
@keyframes stone-land-v130{0%{opacity:.2;transform:translateY(-12px) scale(.9);box-shadow:0 3px 0 #22323e3d}65%{opacity:1;transform:translateY(2px) scale(1.02)}100%{transform:none}}@keyframes stones-enter-v130{0%{opacity:0;transform:translateY(13px) scale(.94)}100%{opacity:1;transform:none}}@keyframes target-reveal-v130{0%{opacity:.25;transform:scale(.82);filter:blur(3px)}100%{opacity:1;transform:none;filter:none}}@keyframes operator-compress-v130{45%{transform:scale(.83);filter:brightness(1.35)}100%{transform:none}}@keyframes target-ring-drift-v130{to{transform:rotate(360deg)}}@keyframes target-almost-v130{50%{transform:scale(1.055);filter:brightness(1.42)}}@keyframes record-reveal-v130{0%{opacity:0;transform:translateY(6px)}100%{opacity:1;transform:none}}
@media(max-width:720px){.answer-area{display:flex;flex-direction:column}.values-heading{order:1}.working-values{order:2}.answer-area>.operator-row{order:3}.calculation-stage{order:4}.builder-instruction{order:5}.math-trail{order:6}.previous-solutions{order:7}.edit-row{order:8}.answer-actions{order:9}.feedback{order:10}.results-panel{order:11}.result-actions #new-puzzle,.result-actions #try-another,.result-actions #share-result{min-height:52px}.result-daily-streak{text-align:center}.round-refreshing .working-tile{animation-duration:.38s}}
@media(prefers-reduced-motion:reduce){.round-refreshing .target-area>strong,.round-refreshing .working-tile,.working-tile.is-new,.target-area.distance-near::after,.target-area.distance-hot::before,.target-area.distance-almost::before,.target-area.distance-almost::after,.result-record{animation:none!important}}

/* v1.32/v1.33 premium progress, arrival and shared challenge modes. */
.arrival-bridge{position:fixed;z-index:9999;inset:0;display:grid;place-content:center;justify-items:center;gap:8px;overflow:hidden;background:radial-gradient(circle,#39218b 0,#12134d 35%,#061027 68%,#020611 100%);color:#eafcff;animation:arrival-clear-v133 .46s ease-out forwards}.arrival-bridge[hidden]{display:none}.arrival-bridge::before,.arrival-bridge i{content:"";position:absolute;left:50%;top:50%;width:84vmin;height:84vmin;border:2px solid #5fe2ff;border-radius:50%;transform:translate(-50%,-50%);box-shadow:0 0 70px #3ed5ff80,0 0 110px #a842ef66 inset;animation:arrival-ring-v133 .46s ease-out forwards}.arrival-bridge i{width:58vmin;height:58vmin;border-color:#d961ff;animation-delay:.03s}.arrival-bridge>span,.arrival-bridge>strong,.arrival-bridge>em,.arrival-bridge>div{position:relative;z-index:2}.arrival-bridge>span{text-transform:uppercase;letter-spacing:.26em;font-size:10px}.arrival-bridge>strong{font-size:clamp(54px,11vw,112px);line-height:.82;text-shadow:0 0 35px #6ce7ff}.arrival-bridge>div{display:flex;gap:8px;margin-top:13px}.arrival-bridge b{display:grid;place-items:center;width:46px;height:46px;border:1px solid #9aeaff70;border-radius:11px;background:#203774cc;box-shadow:0 8px 24px #04091f88;font-size:14px;animation:arrival-stone-v133 .38s ease-out both}.arrival-bridge b:nth-child(2){animation-delay:.035s}.arrival-bridge b:nth-child(3){animation-delay:.07s}.arrival-bridge b:nth-child(4){animation-delay:.105s}.arrival-bridge b:nth-child(5){animation-delay:.14s}.arrival-bridge b:nth-child(6){animation-delay:.175s}.arrival-bridge>em{margin-top:10px;font-style:normal;font-size:12px;letter-spacing:.12em}.portal-arrival main,.portal-arrival .site-header{animation:game-arrive-v133 .42s ease-out both}@keyframes arrival-clear-v133{0%,72%{opacity:1}100%{opacity:0;visibility:hidden}}@keyframes arrival-ring-v133{from{opacity:.72;transform:translate(-50%,-50%) scale(1.55)}to{opacity:.18;transform:translate(-50%,-50%) scale(.88)}}@keyframes arrival-stone-v133{from{opacity:0;transform:translateY(-18px) scale(.86)}to{opacity:1;transform:none}}@keyframes game-arrive-v133{from{opacity:.42;transform:scale(.985)}to{opacity:1;transform:none}}
.game-nav>button:not(.sound-toggle):not(.how-link){min-height:34px;padding:0 10px;border:0;background:transparent;color:#cbd6d9;font:700 10px/1 system-ui,sans-serif}.game-nav>button:hover{color:#fff}.mode-banner{display:grid;grid-template-columns:auto 1fr auto;gap:2px 12px;align-items:center;margin:0 0 12px;padding:10px 12px;border:1px solid #c3d0d238;border-radius:12px;background:#20394bb8}.mode-banner[hidden]{display:none}.mode-banner>span{grid-row:1/3;align-self:stretch;padding:8px 10px;border-radius:8px;background:#72d9da1c;color:#a7e8e7;font-size:9px;font-weight:850;text-transform:uppercase;letter-spacing:.1em}.mode-banner strong{font-size:14px}.mode-banner small{color:#b9c7ca;font-size:10px}.mode-banner button{grid-column:3;grid-row:1/3;min-height:34px;padding:0 11px;border:1px solid #bec9cc42;border-radius:18px;background:transparent;color:#dae3e4;font-size:9px}.mode-sprint .mode-banner>span{background:#f0a15d1c;color:#ffc18c}.mode-route-hunter .mode-banner>span{background:#bd8cff20;color:#d8bdff}.mode-perfect-route .mode-banner>span{background:#e7ca791c;color:#f4dfa3}.challenge-hud{display:flex;justify-content:center;gap:0;margin:0 0 12px;border-block:1px solid #c4ced02d}.challenge-hud[hidden]{display:none}.challenge-hud>span{min-width:110px;padding:9px 18px;text-align:center}.challenge-hud>span+span{border-left:1px solid #c4ced02d}.challenge-hud small{display:block;color:#aebdc2;font-size:8px;text-transform:uppercase;letter-spacing:.1em}.challenge-hud strong{display:block;margin-top:3px;color:#fff3d2;font-size:18px}.progress-dialog{width:min(820px,calc(100% - 24px));max-height:calc(100vh - 24px);overflow:auto}.progress-hero{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:1px;margin-bottom:12px;border-radius:12px;overflow:hidden;background:#bfc9cb38}.progress-hero>div{min-height:112px;padding:20px;background:#20394c}.progress-hero>div:first-child{background:linear-gradient(135deg,#294e5c,#244050)}.progress-hero span{color:#bdc9cd;font-size:10px}.progress-hero strong{display:block;margin-top:10px;color:#fff1c6;font-size:clamp(28px,5vw,44px);line-height:1}.progress-grid{grid-template-columns:repeat(4,1fr)}.progress-grid>div{min-height:76px;padding:14px}.progress-grid>div:nth-child(n){border-bottom:0}.progress-grid>div:nth-child(4){border-right:0}.progress-section{margin-top:14px;padding:14px;border:1px solid #bcc8ca32;border-radius:12px;background:#20394a80}.progress-section-heading{display:flex;justify-content:space-between;align-items:end;margin-bottom:12px}.progress-section-heading span{display:block;color:#9fb0b6;font-size:8px;text-transform:uppercase;letter-spacing:.12em}.progress-section-heading strong{display:block;margin-top:3px;font-size:13px}.progress-section-heading small{color:#d8c887;font-size:10px}.weekly-activity{display:grid;grid-template-columns:repeat(7,1fr);gap:8px}.weekly-day{display:grid;gap:6px;justify-items:center}.weekly-day span{font-size:8px;color:#aebcc0}.weekly-day i{display:flex;align-items:end;width:100%;height:42px;padding:3px;border-radius:7px;background:#172e40}.weekly-day i::after{content:"";width:100%;height:var(--activity,3px);min-height:3px;border-radius:5px;background:linear-gradient(#8adfd2,#4c9fa4)}.weekly-day strong{font-size:9px;color:#e7eeee}.daily-history{display:flex;gap:7px;overflow:auto}.daily-history span{display:grid;gap:3px;min-width:70px;padding:9px;border:1px solid #b9c6c833;border-radius:9px;color:#aebdc1;font-size:9px}.daily-history strong{color:#eff4ef;font-size:11px}.daily-history .complete{border-color:#7cd8ad5e}.daily-history .complete strong{color:#91e2b8}.achievement-list{display:grid;grid-template-columns:repeat(2,1fr);gap:8px}.achievement-item{display:grid;grid-template-columns:26px 1fr;gap:2px 8px;padding:10px;border:1px solid #c7d0d12b;border-radius:9px}.achievement-item i{grid-row:1/3;display:grid;place-items:center;width:26px;height:26px;border-radius:50%;background:#d4b75e18;color:#efd783;font-style:normal}.achievement-item strong{font-size:10px}.achievement-item small{color:#aebcc0;font-size:8px}.challenge-records>div:last-child{display:flex;gap:16px;flex-wrap:wrap}.challenge-records>div:last-child span{color:#aebcc0;font-size:9px}.challenge-records>div:last-child strong{margin-left:5px;color:#f5e5ad}.challenges-dialog{width:min(720px,calc(100% - 24px));border:1px solid #bdc8cb60;border-radius:20px;background:#20384b;color:#f5f7f5;box-shadow:0 28px 85px #07131fbf}.challenges-dialog::backdrop{background:#07131fd1;backdrop-filter:blur(7px)}.challenges-card{position:relative;padding:28px}.challenges-card>.dialog-close{position:absolute;right:16px;top:14px}.challenges-card h2{margin:4px 0 18px;font-size:clamp(25px,4vw,38px)}.featured-daily{display:grid;grid-template-columns:1fr auto;gap:4px 12px;width:100%;padding:16px;border:1px solid #e4cd7b66;border-radius:12px;background:linear-gradient(135deg,#334c58,#263e50);color:#fff;text-align:left}.featured-daily span{font-size:9px;text-transform:uppercase;letter-spacing:.12em;color:#dfcb8a}.featured-daily strong{font-size:14px}.featured-daily em{grid-column:2;grid-row:1/3;align-self:center;color:#f4e2a8;font-size:10px;font-style:normal}.challenge-list{display:grid;gap:1px;margin-top:14px;border:1px solid #bdc8ca35;border-radius:12px;overflow:hidden;background:#bdc8ca35}.challenge-list button{display:grid;grid-template-columns:34px 1fr auto;align-items:center;gap:10px;min-height:72px;padding:10px 14px;border:0;background:#243f52;color:#eef3f2;text-align:left}.challenge-list button:hover{background:#2c4a5d}.challenge-list i{color:#79d8d6;font:700 10px/1 ui-monospace,monospace;font-style:normal}.challenge-list strong,.challenge-list small{display:block}.challenge-list strong{font-size:12px}.challenge-list small{margin-top:3px;color:#adbdc2;font-size:9px}.challenge-list em{color:#dbe5e5;font-size:9px;font-style:normal}.challenge-list button[data-challenge="sprint"] i{color:#ffb678}.challenge-list button[data-challenge="route-hunter"] i{color:#c69bff}.challenge-list button[data-challenge="perfect-route"] i{color:#efd27d}.mode-sprint .target-area::before{border-color:#f1a56570}.mode-route-hunter .target-area::before{border-color:#bd8cff70}.mode-perfect-route .target-area::before{border-color:#e7ca7970}
@media(max-width:720px){.arrival-bridge b{width:38px;height:38px}.game-nav{flex-wrap:wrap}.game-nav>button:not(.sound-toggle):not(.how-link){min-height:42px}.mode-banner{grid-template-columns:auto 1fr}.mode-banner button{grid-column:1/3;grid-row:auto}.challenge-hud>span{min-width:0;flex:1;padding:8px 6px}.progress-hero{grid-template-columns:1fr 1fr}.progress-hero>div:first-child{grid-column:1/3}.progress-grid{grid-template-columns:repeat(2,1fr)}.progress-grid>div:nth-child(2){border-right:0}.weekly-activity{gap:4px}.achievement-list{grid-template-columns:1fr}.challenges-card,.progress-card{padding:24px 15px}.challenge-list button{min-height:68px;padding:9px}.featured-daily{grid-template-columns:1fr}.featured-daily em{grid-column:1;grid-row:auto}.challenge-records>div:last-child{display:grid;gap:7px}}
@media(prefers-reduced-motion:reduce){.arrival-bridge,.arrival-bridge::before,.arrival-bridge i,.arrival-bridge b,.portal-arrival main,.portal-arrival .site-header{animation:none!important}.arrival-bridge{display:none!important}}

/* v1.34 — calmer universe, signature stones, less dashboard chrome. */
body{background:radial-gradient(ellipse at 50% 34%,#526a7b 0,#344d61 27%,transparent 58%),radial-gradient(circle at 84% 18%,#514b7450 0,transparent 28rem),linear-gradient(180deg,#263f55 0,#182f43 50%,#0d2132 100%)}
body::before{opacity:.15;background-size:92px 92px,137px 137px;animation-duration:42s}
.site-header{border-bottom-color:#dce6e52b}.game-nav{gap:22px}.intro{padding-top:28px}.intro .eyebrow{color:#b8cbc9;letter-spacing:.09em}.intro h1{font-weight:650;letter-spacing:-.055em}.intro h1 span{color:#d9d3ab}.intro>p:last-child{color:#bdc9cd}
.game-shell{border:1px solid #d6dfdf3b;border-radius:12px 3px 12px 3px;background:#293f51;box-shadow:0 34px 80px #07192575,inset 0 1px #fff2;overflow:hidden}
.setup-panel{border-bottom-color:#d8e1e12c;background:linear-gradient(90deg,#314a5d,#2c4356)}
.play-panel{background:radial-gradient(ellipse at 50% 23%,#687c89 0,#465d6d 27%,#2c4355 68%,#263d4e 100%)}
.play-panel::before{background:radial-gradient(ellipse at 50% 25%,#fff0c517 0,#d5e7e616 27%,transparent 68%)}
.play-panel::after{content:"";position:absolute;z-index:0;inset:62px 7% auto;height:330px;pointer-events:none;opacity:.23;background:linear-gradient(30deg,transparent 49.7%,#e7eeee16 50%,transparent 50.3%),linear-gradient(-30deg,transparent 49.7%,#e7eeee10 50%,transparent 50.3%);background-size:132px 80px;mask-image:linear-gradient(#000,transparent 88%)}
.game-topbar,.timer-track,.target-area,.answer-area{position:relative;z-index:1}
.round-status,.session-stats,.timer{color:#bbc7ca}.session-stats strong{color:#f6edcf}.timer-track{background:#172c3a80}.timer-track i{background:#85c9c3}
.target-area{border-color:#d5dddc26}.target-area::before{width:154px;height:154px;border-color:#e5e4d65c;background:radial-gradient(circle,#fff9e833 0 17%,#cddfdd20 18% 41%,transparent 42% 52%,#e6eceb17 53% 54%,transparent 55% 70%);box-shadow:inset 0 0 0 13px #dce5e407,0 0 38px #89c8be20}
.target-area::after{width:168px;height:168px;opacity:.46;background:repeating-conic-gradient(from 0deg,#eef0e99a 0 1deg,transparent 1deg 15deg);-webkit-mask:radial-gradient(circle,transparent 0 72%,#000 73% 75%,transparent 76%);mask:radial-gradient(circle,transparent 0 72%,#000 73% 75%,transparent 76%);animation:target-orbit-v134 32s linear infinite}
.target-meta span{color:#c8d1d2;letter-spacing:.04em}.target-meta em{border-color:#d9c57e66;background:#ddc57710;color:#f5dda1}.target-area>strong{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-weight:720;color:#fff8e8;text-shadow:0 3px 0 #303f47,0 8px 28px #1424306b;letter-spacing:-.07em}.distance-readout{color:#d7dfde}
.working-values{gap:12px}.working-tile{min-height:84px;border:1px solid #fffef4;border-bottom:5px solid #a3bab7;border-radius:13px 4px 13px 4px;background:linear-gradient(145deg,#fffdf1 0,#edf0e8 48%,#d7e3df 100%);box-shadow:0 12px 19px #17273359,0 2px 0 #fff inset,0 -1px 0 #9cafaa inset;transition:transform .12s ease,box-shadow .12s ease,filter .12s ease,opacity .14s}
.working-tile::before{left:9px;top:8px;width:14px;height:3px;background:linear-gradient(90deg,#fff,#8fb5b2);opacity:.7}.working-tile::after{content:"";position:absolute;inset:4px;border:1px solid #fff9;border-radius:9px 2px 9px 2px;pointer-events:none}
.working-tile strong{font-weight:760;color:#273941;text-shadow:0 1px #fff}.working-tile small{color:#687b7f;letter-spacing:.02em;text-transform:none}
.working-tile.original.large-number{border-color:#fff8db;border-bottom-color:#b79955;background:linear-gradient(145deg,#fff9e5 0,#f0e5c9 52%,#d8c495 100%);box-shadow:0 12px 20px #17273359,0 2px 0 #fff9 inset,0 -1px 0 #aa8c4f inset}.working-tile.original.large-number::before{background:linear-gradient(90deg,#fff3c2,#bb964e)}
.working-tile:hover:not(:disabled){transform:translateY(-4px);filter:brightness(1.025);box-shadow:0 17px 24px #17273366,0 2px 0 #fff inset,0 0 0 2px #76d4cd4f}.working-tile.selected{transform:translateY(-5px);border-color:#8eddd7;box-shadow:0 18px 26px #14242f6b,0 0 0 2px #70d3cb80,0 0 26px #66cfc641}.working-tile:active:not(:disabled){transform:translateY(-1px) scale(.97)!important}
.operator-row{gap:5px;padding:5px;border:1px solid #c7d1d037;border-radius:10px 3px 10px 3px;background:#263b4a99;box-shadow:inset 0 1px #fff12}.operator-row button{width:44px;height:40px;border:1px solid transparent;border-radius:8px 2px 8px 2px;background:transparent;color:#dce5e4;font-size:18px}.operator-row button:hover:not(:disabled){border-color:#9ecbc7;background:#354f5d;color:#fff}.operator-row button.selected{border-color:#9de1da;background:#dfeceb;color:#26444d;box-shadow:0 2px 0 #749e9a}
.calculation-stage{border-color:#d2d9d833;background:#283d4c8f;color:#e5eceb}.calculation-stage span,.calculation-stage strong{color:#fff8e7}
.math-trail{margin-top:18px;padding-top:13px;border-top:1px solid #d2dada2e}.math-trail>div{align-items:baseline}.math-trail>div small{color:#aebabc}.player-steps::before{left:11px;background:linear-gradient(#c2ddd77a,#9aa9a84a)}.player-steps li{min-height:36px}.player-steps li>span{width:23px;height:23px;border-radius:50%;border-color:#b8d6d1;background:#344e59;color:#f5f5e9;box-shadow:0 0 0 3px #2d4553}.player-steps li strong{font-weight:620;color:#f3f3e8}.player-steps .empty-step::before{background:#c7d7d2}
.edit-row button{border-radius:7px 2px 7px 2px;background:#2e4454}.feedback{border-radius:8px 2px 8px 2px;background:#2a405082!important}.results-panel{border-radius:10px 3px 10px 3px;background:linear-gradient(180deg,#3147578c,#2539486b)}
.sound-toggle{border-color:#c5cece43;background:#293c4b}.sound-toggle[aria-pressed="true"]{color:#aeb8ba;box-shadow:inset 0 0 0 1px #0002}
@keyframes target-orbit-v134{to{transform:rotate(360deg)}}
@media(max-width:720px){
  body{background:radial-gradient(circle at 50% 19%,#536a78 0,transparent 22rem),linear-gradient(180deg,#324a5c,#172b3c)}
  .intro{padding-inline:16px}.intro h1{font-size:clamp(35px,11vw,46px)}.game-shell{width:calc(100% - 12px)}
  .play-panel{padding:11px 12px 22px;background:radial-gradient(ellipse at 50% 17%,#607783 0,#40596a 32%,#293f51 78%)}.play-panel::after{display:none}
  .target-area{min-height:142px}.target-area::before{width:130px;height:130px}.target-area::after{width:142px;height:142px}.target-area>strong{font-size:58px}
  .working-values{grid-template-columns:repeat(3,1fr);gap:9px}.working-tile{min-height:72px}.operator-row{position:sticky;bottom:8px;z-index:9;align-self:center;box-shadow:0 9px 26px #0d1b26a6,inset 0 1px #fff2}.operator-row button{width:48px;height:46px}
  .math-trail{margin-top:14px}.edit-row button{min-height:48px}
}
@media(prefers-reduced-motion:reduce){.target-area::after{animation:none}.working-tile,.operator-row button{transition:none}}