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/* 参考工作台的紫蓝磨砂侧栏，以及 parent.html 的绿调个人空间。 */
body:has(.shell){--primary:#6967ef;--soft:#f0efff;background:radial-gradient(ellipse at 90% 0%,#818afa16,transparent 42%),var(--bg)}html[data-theme=dark] body:has(.shell){--primary:#aaa6ff;--soft:#302d50}.shell .primary{background:linear-gradient(135deg,#6967ef,#819af5)}.topbar{padding:16px 20px;border:1px solid var(--border);border-radius:20px;background:var(--glass);backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px)}body:has(.portal){--primary:#197149;--soft:#dceee4;--bg:#f4f6f1;--text:#18201b;--muted:#68726b;--border:#e3e8e1;background:radial-gradient(circle at 85% -10%,#dcefe4 0,transparent 34rem),var(--bg)}html[data-theme=dark] body:has(.portal){--primary:#88d5ac;--soft:#254b3a;--bg:#121f1b;--text:#edf7f0;--muted:#a7c0b1;--border:#345044;background:radial-gradient(circle at 85% -10%,#294b3d,transparent 34rem),var(--bg)}.portal .hero{background:linear-gradient(135deg,#197149,#4a9872)}.portal .floating-nav{width:min(calc(100% - 24px),480px);justify-content:space-around;border-radius:20px}.portal .floating-nav button{flex:1}.floating-nav:has([data-tab]){width:min(calc(100% - 24px),480px);justify-content:space-around}.floating-nav:has([data-tab]) button{flex:1}.card,.sidebar,.floating-nav{-webkit-backdrop-filter:blur(18px)}.portal{padding-top:calc(26px + env(safe-area-inset-top))}@media(max-width:700px){.topbar{padding:12px}.sidebar.open{animation:drawerIn .3s cubic-bezier(.32,.72,0,1)}@keyframes drawerIn{from{transform:translateX(-100%)}to{transform:none}}}

.brand.compact{margin:0}.theme-control{width:125px;flex-shrink:0}.eyebrow.inverse{color:inherit}

/* Compact teacher workspace: quieter materials, consistent navigation, more room for content. */
body:has(.shell){--primary:#5b5bd6;--soft:#ededfb;--muted:#657184;--shadow:0 6px 24px #24324b08;background:radial-gradient(ellipse at 100% 0%,#858bea0b,transparent 48%),var(--bg)}
html[data-theme=dark] body:has(.shell){--primary:#b7b4ff;--soft:#32314b;--muted:#a7b4c5;--shadow:0 6px 24px #0002}
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.account-name{font-size:13px;font-weight:600;margin:0 8px 12px;overflow-wrap:anywhere}
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.sidebar .bottom .actions{gap:2px;margin-top:6px;flex-wrap:nowrap}
.sidebar .bottom .actions button{justify-content:center;min-height:40px;font-size:12px;padding:8px 4px}
.shell .main{margin-left:232px;padding:16px 8px 64px 0;min-width:0}
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.shell .topbar .tag{font-size:11px;font-weight:500;background:transparent;color:var(--muted);white-space:nowrap}
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.shell h3{font-weight:600;letter-spacing:-.2px}
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.shell .primary:hover{background:#5554cd}
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.shell .student-card h2{margin-top:22px;margin-bottom:12px;font-size:24px}
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.shell #content>.row.between{margin-bottom:16px;gap:14px}
.shell #content>.row.between>p{margin:0}
html[data-theme=dark] .shell .primary{background:#7672e3;color:white}
@media(max-width:900px){.shell .main{margin-left:224px;padding-right:0}.shell .sidebar{width:200px}.shell .grid{grid-template-columns:1fr}}
@media(max-width:700px){
 .shell{padding:0}
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}
@media(prefers-reduced-transparency:reduce){.shell .sidebar,.shell .topbar{background:var(--solid);backdrop-filter:none;-webkit-backdrop-filter:none}}
@media(prefers-contrast:more){.shell .sidebar,.shell .topbar,.shell .card{background:var(--solid);border-color:var(--muted)}}

body:has(.shell){min-height:100dvh;background-attachment:fixed;background-repeat:no-repeat}

@media(max-width:700px){.shell .actions button{flex:1 1 120px}.shell .sidebar .actions button{flex:1;min-width:0}}