:root{color-scheme:dark;--navy:#0e2942;--blue:#1d6489;--gold:#ffd66b;--paper:#f7f2e7}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent;-webkit-user-select:none;user-select:none}[hidden]{display:none!important}html,body{min-height:100%;margin:0;overscroll-behavior:none}body{min-height:100dvh;padding:max(10px,env(safe-area-inset-top)) max(10px,env(safe-area-inset-right)) max(12px,env(safe-area-inset-bottom)) max(10px,env(safe-area-inset-left));background:radial-gradient(circle at 12% 12%,#4fa9bd55,transparent 28%),radial-gradient(circle at 90% 88%,#d8905455,transparent 28%),linear-gradient(145deg,#071927,#173f5c 55%,#5f3b56);color:#fff;font-family:Nunito,"Apple SD Gothic Neo","Malgun Gothic",sans-serif;touch-action:manipulation}
button{font:inherit;color:inherit;touch-action:manipulation}.shell{width:min(100%,820px);margin:auto;display:grid;gap:10px}header{display:flex;align-items:center;justify-content:space-between;gap:12px}header p{margin:0;color:#9edbe4;font-size:10px;font-weight:900;letter-spacing:.18em}h1{margin:2px 0 0;font-size:clamp(23px,6vw,36px);text-shadow:0 3px #071927}nav{display:flex;gap:6px}nav button{width:40px;height:40px;border:1px solid #ffffff45;border-radius:13px;background:#102f48cc;box-shadow:inset 0 1px #ffffff40,0 5px 13px #0004;cursor:pointer}nav button:active{transform:translateY(2px)}
.toolbar{display:grid;grid-template-columns:1.2fr 1fr;gap:8px}.art-picker,.difficulty{display:flex;gap:5px;padding:5px;border:1px solid #ffffff2d;border-radius:14px;background:#0b2338a8}.toolbar button{flex:1;border:0;border-radius:10px;background:transparent;padding:8px 5px;color:#b7cfdd;font-size:12px;font-weight:800;cursor:pointer}.toolbar button.selected{background:linear-gradient(145deg,#f4c75f,#e87967);color:#173047;box-shadow:0 4px 10px #0003}
.hud{display:grid;grid-template-columns:repeat(4,1fr);gap:7px}.hud div{padding:7px;border:1px solid #ffffff30;border-radius:12px;background:#102d45b8;text-align:center}.hud span{display:block;color:#8fc5d5;font-size:9px;font-weight:900;letter-spacing:.12em}.hud strong{display:block;margin-top:2px;font-size:clamp(14px,4vw,19px)}
.puzzle-frame{position:relative;padding:clamp(7px,1.8vw,14px);border:2px solid #ffffff65;border-radius:24px;background:linear-gradient(145deg,#f3dca9,#9e6e5f);box-shadow:0 24px 60px #0006,inset 0 2px #fff8}.board{--size:4;position:relative;z-index:2;display:grid;grid-template-columns:repeat(var(--size),1fr);gap:clamp(1px,.45vw,3px);aspect-ratio:4/3;padding:clamp(3px,.8vw,6px);border-radius:15px;background:#182f3b;touch-action:none;overflow:hidden}.piece{position:relative;min-width:0;border:0;background-repeat:no-repeat;cursor:grab;filter:drop-shadow(0 2px 1px #0007);transition:transform .16s ease,filter .16s ease;clip-path:polygon(0 0,38% 0,38% 8%,62% 8%,62% 0,100% 0,100% 38%,92% 38%,92% 62%,100% 62%,100% 100%,62% 100%,62% 92%,38% 92%,38% 100%,0 100%,0 62%,8% 62%,8% 38%,0 38%)}.piece::after{content:"";position:absolute;inset:7%;border:1px solid #ffffff2e;pointer-events:none}.piece.selected{z-index:5;transform:scale(.92);filter:drop-shadow(0 0 7px #ffe681) brightness(1.14);outline:3px solid #ffe681}.piece.correct::after{border:2px solid #74f5bd;box-shadow:inset 0 0 12px #39d89455}.piece.hint{animation:hint .55s ease-in-out 4}.piece.swapped{animation:swap .3s ease-out}
.preview{position:absolute;z-index:9;inset:0;display:grid;place-items:center;background:#071927e8;backdrop-filter:blur(5px);padding:25px}.preview img{width:min(92%,680px);max-height:82%;object-fit:contain;border:7px solid #f8e5bd;border-radius:16px;box-shadow:0 15px 35px #0008;-webkit-user-drag:none}.preview p{position:absolute;bottom:13px;margin:0;color:#ffe8a6;font-weight:800}
.overlay{position:absolute;z-index:8;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:24px;text-align:center;background:#0a253be5;backdrop-filter:blur(5px)}.overlay #overlay-kicker{margin:0;color:#ffd66b;font-size:11px;font-weight:900;letter-spacing:.2em}.overlay h2{margin:5px 0;font-size:clamp(25px,7vw,44px);text-shadow:0 3px #091c2b}.overlay p{max-width:470px;margin:4px 0;color:#cce4eb;line-height:1.5}.overlay button{margin-top:14px;border:0;border-radius:999px;background:linear-gradient(#ffe486,#eaa45e);color:#173047;padding:13px 29px;font-weight:1000;box-shadow:0 6px 0 #9f5f55,0 12px 25px #0006;cursor:pointer}.overlay button:active{transform:translateY(4px);box-shadow:0 2px 0 #9f5f55}.message{min-height:22px;margin:0;text-align:center;color:#d8edf1;font-size:13px;font-weight:800}
@keyframes hint{50%{transform:scale(.9);filter:brightness(1.35) drop-shadow(0 0 8px #ffe681)}}@keyframes swap{50%{transform:scale(.82) rotate(2deg)}}
@media(max-width:580px){body{padding-left:6px;padding-right:6px}.toolbar{grid-template-columns:1fr}.toolbar button{font-size:11px}.puzzle-frame{border-radius:18px}.hud{gap:4px}.hud div{padding:6px 2px}}
@media(max-height:650px) and (orientation:landscape){.shell{width:min(98vw,920px);grid-template-columns:minmax(230px,.85fr) minmax(410px,1.65fr);align-items:start}.puzzle-frame{grid-column:2;grid-row:1/6}header,.toolbar,.hud,.message{grid-column:1}.toolbar{grid-template-columns:1fr}.hud{grid-template-columns:repeat(2,1fr)}}