:root{--ink:#132238;--muted:#64748b;--line:#dbe4ee;--panel:#ffffff;--canvas:#f3f7fb;--blue:#2563eb;--blue-dark:#1d4ed8;--green:#147a55;--red:#b42318;--amber:#9a6700}*{box-sizing:border-box}body,html{min-height:100%}body{margin:0;background:var(--canvas);color:var(--ink);font-family:Arial,Noto Sans TC,Microsoft JhengHei,sans-serif;font-size:16px}button,input{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.62}a{color:var(--blue-dark)}.public-shell{min-height:100dvh;display:grid;place-items:center;padding:24px 16px;background:radial-gradient(circle at 20% 0,#e7f0ff 0,transparent 34%),var(--canvas)}.hero-card,.join-card{width:min(100%,480px);background:var(--panel);border:1px solid rgba(219,228,238,.95);border-radius:22px;padding:32px 24px;box-shadow:0 22px 60px rgba(30,64,98,.1)}.brand-mark{width:44px;height:44px;display:grid;place-items:center;border-radius:13px;background:var(--blue);color:#fff;font-weight:800;letter-spacing:.04em;margin-bottom:22px}.eyebrow{margin:0 0 8px;color:var(--blue-dark);font-size:13px;font-weight:700;letter-spacing:.1em}h1,h2,h3,p{margin-top:0}h1{margin-bottom:14px;font-size:clamp(28px,7vw,38px);line-height:1.18;letter-spacing:-.025em}h2{font-size:22px}h2,h3{margin-bottom:8px}h3{font-size:18px}.lead{margin-bottom:24px;color:var(--muted);line-height:1.7}.notice-box{display:grid;grid-gap:4px;gap:4px;margin:20px 0 24px;padding:14px 16px;border-radius:14px;background:#f0f6ff;color:#425574;line-height:1.55}.text-link{font-size:14px;font-weight:700}.admin-form,.join-form{display:grid;grid-gap:10px;gap:10px}label{font-weight:700;color:#334155}input{width:100%;min-height:50px;border:1px solid #cbd5e1;border-radius:12px;padding:0 14px;background:#fff;color:var(--ink);outline:none}input:focus{border-color:var(--blue);box-shadow:0 0 0 3px rgba(37,99,235,.14)}.primary-button,.secondary-button{min-height:48px;border-radius:12px;padding:0 16px;font-weight:700;border:1px solid transparent;transition:background .15s ease,border-color .15s ease}.primary-button{margin-top:8px;background:var(--blue);color:#fff}.primary-button:hover:not(:disabled){background:var(--blue-dark)}.secondary-button{background:#fff;color:#334155;border-color:#cbd5e1}.secondary-button:hover:not(:disabled){background:#f8fafc;border-color:#94a3b8}.course-meta,.helper-text,.status-text{color:var(--muted);font-size:14px;line-height:1.55}.helper-text{margin:4px 0 0}.status-text{margin:8px 0 0}.alert{margin:0 0 16px;padding:12px 14px;border-radius:12px;line-height:1.5;font-size:14px}.alert.error{background:#fff1f0;color:var(--red);border:1px solid #ffd2cf}.alert.warning{background:#fff8e6;color:var(--amber);border:1px solid #f2dfaa}.alert.success{background:#edfbf4;color:var(--green);border:1px solid #bce9d0}.admin-shell{width:min(100%,1080px);margin:0 auto;padding:28px 16px 64px}.admin-header{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin-bottom:22px}.admin-header h1{margin-bottom:0}.admin-card{margin-bottom:20px;padding:24px;background:var(--panel);border:1px solid var(--line);border-radius:18px;box-shadow:0 12px 35px rgba(30,64,98,.06)}.section-heading{margin-bottom:18px}.section-heading p{margin-bottom:0;color:var(--muted);line-height:1.55}.course-list{display:grid;grid-gap:12px;gap:12px}.course-item{padding:18px;border:1px solid var(--line);border-radius:14px;background:#fbfdff}.course-item-title{display:flex;flex-wrap:wrap;align-items:center;gap:10px}.course-item-title h3{margin-bottom:0}.status-pill{padding:4px 9px;border-radius:999px;font-size:12px;font-weight:700}.status-pill.active{background:#e8f8f0;color:var(--green)}.status-pill.inactive{background:#f1f5f9;color:#64748b}.course-meta{margin:8px 0 0}.join-url{margin:12px 0 0;color:#334155;font-size:14px;word-break:break-all}.course-actions{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}.course-actions .secondary-button{min-height:40px;font-size:14px}.log-table-wrap{overflow-x:auto;margin-top:14px;border-top:1px solid var(--line);padding-top:12px}table{width:100%;border-collapse:collapse;font-size:14px}td,th{padding:9px 8px;text-align:left;border-bottom:1px solid #e7edf4;vertical-align:top}th{color:#475569;font-size:12px}.empty-state{margin-bottom:0;color:var(--muted)}.meeting-shell{background:#000}#zmmtg-root,.meeting-shell{min-height:100dvh}@media (min-width:700px){.public-shell{padding:48px 24px}.hero-card,.join-card{padding:40px 36px}.admin-shell{padding:48px 24px 80px}}