:root{color:#183347;font-family:Inter,Noto Sans TC,Microsoft JhengHei,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:#7fdcea;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100svh;overflow:hidden}html,body,#root{height:100%}button,select{font:inherit}.app-shell{height:100svh;display:grid;place-items:center;overflow:hidden;padding:clamp(12px,2.4svh,24px) 18px;background-image:url(/background.jpg);background-size:cover;background-position:center;background-repeat:no-repeat;background-attachment:fixed;background-color:#7fdcea}.game-panel{width:min(1080px,100%);max-height:calc(100svh - clamp(24px,4.8svh,48px));--frame-height-budget: 392px;display:grid;gap:clamp(11px,1.45svh,16px);padding:clamp(17px,2.3svh,24px);border:1px solid rgb(255 255 255 / .58);border-radius:24px;background:#ffffff61;box-shadow:0 20px 60px #14536933;-webkit-backdrop-filter:blur(18px) saturate(1.24);backdrop-filter:blur(18px) saturate(1.24)}.top-bar{display:flex;align-items:end;justify-content:space-between;gap:18px}.brand-block{min-width:220px}.eyebrow{margin:0 0 4px;color:#1a7898;font-size:.78rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase}h1{margin:0;color:#17354b;font-size:clamp(1.55rem,3.6vw,2.45rem);line-height:1.08}.settings-row{display:flex;flex-wrap:wrap;align-items:center;justify-content:flex-end;gap:10px}.select-field,.language-toggle{min-height:44px;display:inline-flex;align-items:center;gap:8px;padding:6px;border:1px solid rgb(255 255 255 / .66);border-radius:999px;background:#ffffff7a;box-shadow:inset 0 1px #ffffff8f}.select-field span{padding-left:8px;color:#226079;font-size:.92rem;font-weight:800}select{height:32px;border:0;border-radius:999px;padding:0 28px 0 12px;color:#16364b;background:#ffffffe0;cursor:pointer}.language-toggle button{height:32px;border:0;border-radius:999px;padding:0 13px;color:#236179;background:transparent;font-weight:900;cursor:pointer}.language-toggle button.active{color:#fff;background:#188fb3;box-shadow:0 8px 18px #188fb347}.frame-card{position:relative;aspect-ratio:4 / 3;width:min(720px,100%,max(500px,calc((100svh - var(--frame-height-budget)) * 4 / 3)));min-width:min(100%,360px);margin:0 auto;overflow:hidden;display:grid;place-items:center;border:3px solid rgb(255 255 255 / .78);border-radius:20px;background:linear-gradient(135deg,#ffffffa6,#ffffff3d),#d6f8ff;box-shadow:0 24px 60px #0f435f3d,inset 0 1px #ffffffe0}.frame-card img{width:100%;height:100%;object-fit:contain;opacity:0;transform:scale(.985);transition:opacity .18s ease,transform .22s ease}.frame-card img.ready{opacity:1;transform:scale(1)}.image-skeleton{position:absolute;inset:0;display:grid;place-items:center;color:#23718c;font-weight:900;background:linear-gradient(90deg,transparent,rgb(255 255 255 / .42),transparent),#d6f8ffb8;background-size:220% 100%;animation:shimmer 1.1s linear infinite}.answer-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin-top:clamp(4px,.8svh,10px)}.answer-button{min-height:56px;border:1px solid rgb(255 255 255 / .7);border-radius:18px;padding:12px 16px;color:#15364b;background:#ffffffb8;box-shadow:0 10px 26px #14526921,inset 0 1px #ffffffbf;font-size:1rem;font-weight:900;line-height:1.3;cursor:pointer;transition:transform .15s ease,box-shadow .15s ease,background .15s ease,color .15s ease}.answer-button:not(:disabled):hover{transform:translateY(-2px);background:#fff8c7;box-shadow:0 16px 34px #14526933}.answer-button.correct{color:#fff;background:linear-gradient(135deg,#19b36b,#0d8f9f)}.answer-button.wrong{color:#fff;background:linear-gradient(135deg,#ff5f68,#e74b8b)}.answer-button.dimmed{opacity:.5}.result-row{min-height:42px;display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:12px}.result{font-size:1.02rem;font-weight:950}.result.correct{color:#057846}.result.wrong{color:#c52250}.next-button{min-height:38px;border:0;border-radius:999px;padding:0 22px;color:#fff;background:#17354b;box-shadow:0 14px 28px #17354b3d;font-weight:950;cursor:pointer}.status-message{display:grid;min-height:120px;place-items:center;color:#1d5d76;font-size:1.05rem;font-weight:900;text-align:center}.status-message.error{color:#bf2b4d}.source-credit{min-height:24px;margin:0;display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:0 4px;color:#17354bad;font-size:.78rem;font-weight:700;line-height:1.35;text-align:center}.source-credit a{color:inherit;text-decoration:underline;text-underline-offset:3px}@keyframes shimmer{0%{background-position:120% 0}to{background-position:-120% 0}}@media(max-width:720px){body{overflow:auto}.app-shell{min-height:100svh;height:auto;overflow:visible;padding:12px 10px;align-items:start}.game-panel{max-height:none;--frame-height-budget: 430px;gap:14px;padding:14px;border-radius:22px}.top-bar{align-items:stretch;flex-direction:column}.settings-row{justify-content:stretch}.select-field,.language-toggle{flex:1 1 auto;justify-content:center}.frame-card{width:100%;min-width:0;border-radius:18px}.answer-grid{grid-template-columns:1fr;gap:10px;margin-top:2px}.answer-button{min-height:54px;border-radius:16px}.source-credit{min-height:30px;padding-top:2px;font-size:.72rem}}@media(min-width:768px){.app-shell{background-image:url(/bg-desktop.jpg);background-position:center bottom}}