:root{color-scheme:light;--paper:#faf8f4;--ink:#282927;--muted:#66635d;--wine:#811b2c;--line:#dedad1;font-family:system-ui,-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;font-size:16px}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink)}[hidden]{display:none!important}a{color:inherit;text-underline-offset:5px}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer}button,.button{transition:background .16s,color .16s}a:focus-visible,button:focus-visible{outline:3px solid #b46e15;outline-offset:5px}::selection{background:#f0d8b2;color:#282927}.brand{max-width:1160px;margin:auto;padding:30px 30px 0;display:flex;gap:14px;align-items:center;font-weight:700;letter-spacing:.03em}.brand img{border-radius:8px;object-fit:contain}.brand-en{display:block;font-size:11px;margin-top:3px;letter-spacing:.12em}.teacher-label{margin-left:auto;color:var(--muted);font-size:14px;font-weight:500;letter-spacing:0}.landing{max-width:1100px;margin:auto;padding:62px 30px 20px}.intro{margin-bottom:40px}h1,h2,p{margin:0}.intro h1{font-size:3.5rem;line-height:1.15;letter-spacing:-.03em}.intro p{font-size:20px;line-height:1.7;margin-top:18px;color:var(--muted)}.centres{border-top:1px solid var(--line)}.centre{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:32px 0;border-bottom:1px solid var(--line)}.centre h2{font-size:36px;line-height:1.2;letter-spacing:-.025em}.centre-title p{margin-top:7px;font-size:15px;color:var(--muted)}.actions{display:flex;gap:12px}.button{display:inline-flex;justify-content:center;align-items:center;gap:24px;padding:16px 22px;border-radius:10px;text-decoration:none;min-height:56px;font-size:17px;font-weight:600;white-space:nowrap}.primary{background:var(--wine);color:white}.primary:hover{background:#641322}.secondary{background:#ece8df;color:var(--ink)}.secondary:hover{background:#dfd9cc}svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}.how-to{margin-top:34px;display:flex;align-items:baseline;gap:42px}.how-to h2{font-size:17px;white-space:nowrap}.how-to ol{margin:0;padding-left:20px;display:flex;flex-wrap:wrap;gap:8px 34px;color:var(--muted);font-size:15px;line-height:1.8}footer{margin-top:46px;padding:24px 0 14px;display:flex;justify-content:space-between;align-items:center;gap:16px;color:var(--muted);font-size:14px}.text-button{border:0;background:none;color:var(--wine);padding:10px 0;text-decoration:underline;text-underline-offset:5px}.projection{min-height:100dvh;background:#101729;color:white;display:flex;flex-direction:column}.project-toolbar{display:flex;align-items:center;gap:20px;padding:18px 34px;border-bottom:1px solid #30394c}.back{text-decoration:none;font-size:15px;color:#d6dfed}.switcher{display:flex;gap:4px;margin:auto}.switcher a{text-decoration:none;padding:10px 20px;border-radius:7px;color:#cbd4e4;font-size:15px}.switcher a[aria-current=page]{background:#e8e2d6;color:#101729}.fullscreen{border:1px solid #566177;border-radius:7px;min-height:42px;background:transparent;color:white;padding:8px 14px;display:flex;gap:12px;align-items:center}.fullscreen:hover,.copy-url:hover{background:#28334a}.project-content{width:100%;max-width:1540px;flex:1;margin:auto;display:grid;grid-template-columns:1fr 1fr;gap:24px;align-items:center;padding:24px 5vw}.project-brand{font-size:21px;color:#d0d9e9;margin-bottom:28px}.project-copy h1{font-size:clamp(48px,6.7vw,96px);line-height:1.1;letter-spacing:-.035em;outline:none}.scan-prompt{font-size:clamp(24px,3.1vw,45px);line-height:1.5;margin-top:32px;font-weight:600}.check-centre{color:#cbd4e4;margin-top:14px;font-size:18px}.project-actions{display:flex;gap:18px;align-items:center;margin-top:32px}.light{background:#f1e7d5;color:#101729}.light:hover{background:white}.copy-url{border:0;background:transparent;color:#e6edf9;padding:14px 8px;border-radius:7px}.project-url{display:inline-block;font-size:clamp(13px,1.3vw,19px);margin-top:18px;color:#e9c786;overflow-wrap:anywhere;line-height:1.5}.qr-wrap{text-align:center;min-width:0}.qr-wrap img{max-width:100%;width:auto;height:auto;max-height:calc(100dvh - 140px);object-fit:contain;vertical-align:middle}.keyboard-hint{font-size:12px;color:#b7c2d5;text-align:center;padding:0 20px 14px}.status{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);max-width:calc(100vw - 32px);width:max-content;background:#fff;color:#20242a;border:1px solid #d7d1c4;box-shadow:0 6px 24px #0002;border-radius:10px;padding:13px 20px;z-index:10;font-size:15px;overflow-wrap:anywhere}.status a{color:#811b2c}.projection:fullscreen{overflow:auto}@media(min-width:1600px){.project-content{padding-inline:60px}}@media(max-width:740px){.brand{padding:22px 22px 0}.brand img{width:52px;height:52px}.landing{padding:42px 22px 12px}.intro{margin-bottom:28px}.intro h1{font-size:2.5rem}.intro p{font-size:17px}.centre{align-items:flex-start;flex-direction:column;gap:20px;padding:26px 0}.centre h2{font-size:31px}.actions{width:100%;gap:10px}.actions .button{flex:1;gap:12px;padding:14px 12px;font-size:16px}.how-to{display:block;margin-top:28px}.how-to ol{display:block;margin-top:10px;line-height:2}.how-to h2{font-size:16px}footer{margin-top:26px;align-items:flex-start;flex-direction:column;gap:2px}.project-toolbar{padding:12px 16px;gap:10px;flex-wrap:wrap}.switcher{order:3;width:100%;justify-content:center}.back{font-size:14px}.fullscreen{margin-left:auto;font-size:14px;padding:7px 10px}.project-content{grid-template-columns:1fr;padding:22px 24px;gap:24px}.project-brand{font-size:15px;margin-bottom:10px}.project-copy h1{font-size:46px}.scan-prompt{font-size:24px;margin-top:18px}.scan-prompt br{display:none}.check-centre{font-size:15px;margin-top:8px}.project-actions{margin-top:20px;gap:12px}.project-actions .button{font-size:15px;min-height:48px;padding:12px 17px}.project-url{font-size:13px;margin-top:12px}.qr-wrap img{max-height:none;width:min(100%,420px)}.keyboard-hint{display:none}}@media(max-height:600px) and (min-width:741px){.project-toolbar{padding-block:9px}.project-brand{margin-bottom:12px;font-size:16px}.project-copy h1{font-size:50px}.scan-prompt{font-size:27px;margin-top:14px}.project-actions{margin-top:14px}.project-content{padding-block:12px}.check-centre{margin-top:8px}.qr-wrap img{max-height:calc(100dvh - 112px)}}@media(prefers-reduced-motion:reduce){*{transition:none!important}}

.sheet-link{border:1px solid #c9c1b4;color:var(--wine);background:transparent}.sheet-link:hover{background:#eee9df}@media(max-width:1000px) and (min-width:741px){.centre{align-items:flex-start;flex-direction:column}.actions{width:100%}}@media(max-width:740px){.actions{flex-wrap:wrap}.actions .sheet-link{flex-basis:100%}}