:root{color-scheme:light;--background:#f4f6f2;--foreground:#141813;--muted:#5f695c;--line:#cfd8ca;--panel:#ffffff;--field:#eef3eb;--accent:#247d53;--accent-strong:#155a39;--lime:#a4d65e;--berry:#dc3f62;--amber:#f0b84c;--shadow:0 18px 50px rgba(20,24,19,0.11)}*{box-sizing:border-box}body,html{min-height:100%}body{margin:0;background:linear-gradient(135deg,rgba(164,214,94,.16),transparent 36%),linear-gradient(315deg,rgba(240,184,76,.16),transparent 38%),var(--background);color:var(--foreground);font-family:Arial,Noto Sans TC,sans-serif}a{color:inherit}button,input{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.55}.game-shell{min-height:100vh;display:grid;grid-template-rows:auto 1fr}.game-topbar{min-height:64px;display:flex;align-items:center;justify-content:space-between;gap:20px;padding:0 32px;border-bottom:1px solid rgba(207,216,202,.88);background:rgba(255,255,255,.86);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px)}.brand-link{display:inline-flex;align-items:center;gap:10px;color:var(--accent-strong);font-size:18px;font-weight:900;letter-spacing:0;text-decoration:none}.brand-link:before{width:28px;height:28px;border-radius:7px;background:linear-gradient(90deg,transparent 44%,rgba(255,255,255,.52) 44% 56%,transparent 56%),var(--accent);content:""}.nav-links{display:flex;gap:8px;align-items:center}.nav-links a{min-height:38px;display:inline-flex;align-items:center;border-radius:6px;padding:0 12px;color:var(--muted);font-size:14px;font-weight:700;text-decoration:none}.nav-links a:focus-visible,.nav-links a:hover{background:var(--field);color:var(--accent-strong)}.game-main,.leaderboard-main{width:min(1180px,calc(100% - 40px));margin:0 auto;padding:36px 0}.play-area{display:grid;grid-template-columns:minmax(320px,1fr) minmax(300px,380px);grid-gap:28px;gap:28px;align-items:start}.game-board-wrap,.game-panel,.leaderboard-hero,.ranking-table{border:1px solid var(--line);border-radius:8px;background:rgba(255,255,255,.92);box-shadow:var(--shadow)}.game-board-wrap{padding:clamp(14px,2.2vw,24px)}.score-strip{min-height:48px;display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:14px;color:var(--muted);font-size:15px}.score-strip strong{color:var(--accent-strong);font-size:24px}.game-board{width:min(100%,720px);aspect-ratio:1;display:grid;grid-template-columns:repeat(18,1fr);grid-gap:clamp(2px,.45vw,5px);gap:clamp(2px,.45vw,5px);margin:0 auto;border:10px solid #253525;border-radius:8px;background:#253525}.board-cell{aspect-ratio:1;border-radius:3px;background:#dde9d6}.board-cell:nth-child(odd){background:#d4e2cc}.board-cell.snake-body:nth-child(odd),.board-cell.snake-head:nth-child(odd),.snake-body,.snake-head{background:var(--accent)}.snake-head{box-shadow:inset 0 0 0 3px #0f4c32}.board-cell.food:nth-child(odd),.food{background:var(--berry);box-shadow:inset 0 0 0 3px #ffffff}.game-panel{padding:24px}.kicker{margin:0 0 10px;color:var(--accent);font-size:13px;font-weight:900;text-transform:uppercase}.kicker,h1{letter-spacing:0}h1{margin:0;font-size:clamp(34px,4.2vw,56px);line-height:1.04}.game-panel h1{font-size:clamp(30px,3.4vw,46px)}.start-form{display:grid;grid-gap:10px;gap:10px;margin-top:24px}.start-form label{color:var(--muted);font-size:14px;font-weight:700}.start-form input{min-height:46px;width:100%;border:1px solid var(--line);border-radius:6px;background:var(--field);color:var(--foreground);padding:0 13px;outline:none}.start-form input:focus{border-color:var(--accent);box-shadow:0 0 0 3px rgba(36,125,83,.16)}.button{min-height:44px;display:inline-flex;align-items:center;justify-content:center;border:1px solid var(--accent);border-radius:6px;background:var(--accent);color:#ffffff;padding:0 16px;font-weight:800;text-decoration:none}.button:focus-visible,.button:hover{background:var(--accent-strong)}.button.secondary{background:#ffffff;color:var(--accent-strong)}.button.secondary:focus-visible,.button.secondary:hover{background:var(--field)}.button.wide{width:100%;margin-top:16px}.result-box{display:grid;grid-gap:6px;gap:6px;margin-top:18px;border:1px solid rgba(220,63,98,.28);border-radius:8px;background:rgba(220,63,98,.08);padding:14px}.result-box span{color:var(--muted);font-size:14px;font-weight:700}.result-box strong{color:#9d203e;font-size:22px}.pad{width:184px;display:grid;grid-template-columns:repeat(3,52px);grid-gap:8px;gap:8px;margin:20px auto 0;justify-content:center}.pad button{width:52px;height:52px;border:1px solid var(--line);border-radius:8px;background:var(--field);color:var(--accent-strong);font-size:24px;font-weight:900}.pad button:first-child{grid-column:2}.pad button:focus-visible,.pad button:hover{border-color:var(--accent);background:#ffffff}.leaderboard-main{display:grid;grid-gap:20px;gap:20px}.leaderboard-hero{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;padding:28px}.leaderboard-copy{margin:12px 0 0;color:var(--muted);font-size:17px}.best-score{min-width:150px;display:grid;grid-gap:4px;gap:4px;border:1px solid var(--line);border-radius:8px;background:var(--field);padding:16px;text-align:right}.best-score span{color:var(--muted);font-size:14px;font-weight:700}.best-score strong{color:var(--accent-strong);font-size:42px}.ranking-table{overflow:hidden}.ranking-head,.ranking-row{display:grid;grid-template-columns:90px minmax(120px,1fr) 110px 150px;grid-gap:14px;gap:14px;align-items:center;padding:16px 20px}.ranking-head{background:var(--field);color:var(--muted);font-size:13px;font-weight:900;text-transform:uppercase}.ranking-head,.ranking-row{border-bottom:1px solid var(--line)}.ranking-row{min-height:66px}.ranking-row:last-child{border-bottom:0}.ranking-row strong{color:var(--accent-strong);font-size:20px}.ranking-row span:nth-child(2){font-weight:800;overflow-wrap:anywhere}.ranking-row span:nth-child(3){color:#9d203e;font-weight:900}.ranking-row time{color:var(--muted)}.empty-state{min-height:170px;display:grid;place-content:center;grid-gap:8px;gap:8px;padding:26px;color:var(--muted);text-align:center}.empty-state strong{color:var(--foreground);font-size:22px}.leaderboard-actions{display:flex;flex-wrap:wrap;gap:12px}@media (max-width:860px){.game-topbar{padding:0 20px}.leaderboard-hero,.play-area{grid-template-columns:1fr}.play-area{display:flex;flex-direction:column}.game-board-wrap,.game-panel{width:100%}.game-panel{order:-1}.leaderboard-hero{display:grid;align-items:start}.best-score{width:100%;text-align:left}.ranking-head{display:none}.ranking-row{grid-template-columns:64px 1fr;gap:8px 12px}.ranking-row span:nth-child(3),.ranking-row time{grid-column:2}}@media (max-width:520px){.game-topbar{align-items:flex-start;flex-direction:column;padding:14px 20px}.game-main,.leaderboard-main{width:min(100% - 24px,1180px);padding:18px 0}.game-panel,.leaderboard-hero{padding:18px}.game-panel h1,h1{font-size:30px}.score-strip{align-items:flex-start;flex-direction:column;gap:4px}.game-board{border-width:7px;gap:2px}}