:root{font-family:"Segoe UI","Microsoft YaHei",sans-serif;color:#25364b;background:#f4f7fa;font-size:16px;--blue:#2769bd;--line:#dbe3ec;--ink:#182b40}
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78px)}.workspace.student{grid-template-columns:1fr}.sidebar{background:#fff;border-right:1px solid var(--line);overflow:auto}.sidebar section{padding:24px 20px}.library{border-bottom:1px solid var(--line)}.section-heading{display:flex;align-items:center;justify-content:space-between}.section-heading h2{margin-bottom:16px}.section-heading span{font:13px Consolas,monospace;color:#8191a4}.upload-button{display:block;text-align:center;color:var(--blue);border-style:dashed;background:#f6f9fc;font-size:14px}.document-list{display:flex;flex-direction:column;gap:8px;margin-top:20px;max-height:35vh;overflow:auto}.document-item{text-align:left;font-size:14px;padding:12px;line-height:1.6;word-break:break-word}.document-item small{display:block;color:#7b8b9e;font:12px Consolas,monospace;margin-top:4px}.document-item.selected{border-color:var(--blue);background:#edf3fa;box-shadow:inset 3px 0 var(--blue)}.class-controls h2{margin-bottom:14px}.class-controls .primary,.class-controls .secondary{width:100%;font-size:14px}.code-label{font-size:13px;color:#6d829a}.code-label strong{display:block;font:23px Consolas,monospace;color:var(--ink);letter-spacing:3px;margin:10px 0 16px}.room-resume{width:100%;text-align:left;font-size:13px;margin-top:10px}.presentation{min-width:0;display:flex;flex-direction:column;padding:24px 28px 16px;overflow:hidden}.presentation-heading{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-shrink:0;margin-bottom:18px}.presentation-heading h1{font-size:20px;font-weight:600;margin:6px 0 0;line-height:1.5}.page-label{font:18px Consolas,monospace;white-space:nowrap;color:#6d829a}.canvas-area{background:var(--ink);border-radius:9px;flex:1;min-height:120px;display:flex;align-items:center;justify-content:center;padding:14px;position:relative;overflow:hidden}.empty-canvas{text-align:center;color:#bac8d7;padding:25px}.empty-symbol{font:70px Consolas,monospace;color:#8298b2;display:block;margin-bottom:20px}.empty-canvas h2{font-weight:500}.empty-canvas p{font-size:14px;color:#8fa4bc}.slide-frame{position:relative;flex-shrink:0;max-width:100%;max-height:100%;aspect-ratio:16/9;overflow:hidden;box-shadow:0 8px 35px #06101d50;user-select:none}.slide-frame img{width:100%;height:100%;display:block;object-fit:fill}.slide-frame svg{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}.slide-frame.pen{touch-action:none;cursor:crosshair}.slide-frame.laser-mode{touch-action:none;cursor:crosshair}.laser{position:absolute;width:13px;height:13px;border-radius:50%;background:#ff523e;box-shadow:0 0 0 5px #ff523e30,0 0 15px #ff523e;transform:translate(-50%,-50%);pointer-events:none}.canvas-message{position:absolute;background:#102034dc;color:white;padding:14px 22px;border-radius:8px;max-width:80%;text-align:center;line-height:1.6;font-size:14px}.presentation-footer{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:16px 0 13px;flex-shrink:0;flex-wrap:wrap}.navigation,.tools{display:flex;align-items:center;gap:6px;font-size:14px}.navigation label{display:flex;align-items:center;gap:5px;color:#6d829a}.navigation input{width:57px;padding:8px;text-align:center;appearance:textfield}.navigation input::-webkit-inner-spin-button{appearance:none}.navigation button,.tools button{padding:8px 10px}.tools button.active{color:var(--blue);border-color:#7da9de;background:#e8f1fc}.color-label{padding:3px;border:1px solid var(--line);border-radius:6px;height:34px}.color-label input{padding:0;width:28px;height:26px;cursor:pointer;border:none}.page-track{height:3px;background:#dce4ed;flex-shrink:0}.page-track div{height:100%;background:var(--blue);width:0;transition:width .2s}.presentation:fullscreen{background:#f4f7fa;padding:14px}.presentation:fullscreen .presentation-heading{margin-bottom:10px}.presentation:fullscreen .canvas-area{border-radius:0}.presentation:fullscreen .presentation-footer{padding:8px 0}#toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);background:#25364b;color:#fff;padding:14px 22px;border-radius:8px;box-shadow:0 6px 20px #10203430;max-width:90vw;z-index:10;font-size:14px;line-height:1.6}#toast.error{background:#943c36}dialog{border:1px solid var(--line);border-radius:12px;width:420px;max-width:90vw;padding:28px;color:inherit}dialog::backdrop{background:#10203470}dialog label{font-size:14px;display:block;margin-top:16px}dialog input{margin-top:8px}.dialog-actions{display:flex;justify-content:flex-end;gap:8px;margin-top:24px}
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@media(max-width:1000px){.workspace{grid-template-columns:235px 1fr}.presentation{padding:20px 16px 12px}.topbar{padding:0 18px}.tools{gap:4px}.tools button{padding:8px}.top-actions{gap:2px}.brand small{display:none}}
@media(max-width:700px){.topbar{height:auto;min-height:68px;padding:12px 16px;flex-wrap:wrap}.brand{font-size:17px}.brand-mark{width:34px;height:34px;font-size:19px}.top-actions{font-size:12px;flex-wrap:wrap}.top-actions button{font-size:12px;padding:6px}.entry{margin:40px auto;padding:0 20px}.entry-title h1{font-size:27px;line-height:1.5}.entry-forms{grid-template-columns:1fr;gap:16px}.entry-card{padding:24px}.workspace{height:auto;min-height:calc(100dvh - 100px);grid-template-columns:1fr;display:flex;flex-direction:column}.sidebar{border-right:none;border-bottom:1px solid var(--line);display:grid;grid-template-columns:1fr 1fr;max-height:270px;flex-shrink:0}.sidebar section{padding:16px}.document-list{max-height:115px;margin-top:10px}.document-item{padding:8px;font-size:13px}.library{border-bottom:none;border-right:1px solid var(--line)}.sidebar h2{font-size:16px}.sidebar .hint{font-size:12px}.code-label strong{font-size:19px;letter-spacing:2px;margin:7px 0}.presentation{flex:1;min-height:430px;padding:18px 12px 12px}.presentation-heading h1{font-size:16px}.canvas-area{min-height:240px;padding:6px}.presentation-footer{padding:12px 0;gap:10px}.tools,.navigation{font-size:12px}.navigation input{padding:6px;width:48px}.student .presentation{height:calc(100dvh - 105px);min-height:350px}.student .presentation-heading{margin-bottom:10px}.student .canvas-area{min-height:120px}.student .presentation-footer{justify-content:center}.presentation:fullscreen{min-height:0;height:100dvh}.presentation:fullscreen .canvas-area{min-height:0}.eyebrow{font-size:11px}}
@media(prefers-reduced-motion:reduce){*{transition:none!important}}