:root{--bg: #f5f6f8;--panel: #ffffff;--text: #1a1d21;--muted: #6b7280;--border: #e3e5e8;--accent: #06c755;--accent-dark: #05a648;--danger: #e5484d;color-scheme:light dark}@media (prefers-color-scheme: dark){:root{--bg: #16181c;--panel: #1f2226;--text: #f2f3f5;--muted: #9aa0a8;--border: #2c2f34}}*{box-sizing:border-box}body{margin:0;font-family:-apple-system,Segoe UI,PingFang TC,Noto Sans TC,sans-serif;background:var(--bg);color:var(--text)}.app{display:flex;flex-direction:column;min-height:100vh}.topbar{display:flex;align-items:center;gap:2rem;padding:1rem 1.5rem;background:var(--panel);border-bottom:1px solid var(--border)}.topbar h1{font-size:1.1rem;margin:0;white-space:nowrap}.topbar nav{display:flex;gap:1.25rem}.topbar nav a{color:var(--muted);text-decoration:none;font-weight:500;padding-bottom:4px}.topbar nav a.active{color:var(--accent-dark);border-bottom:2px solid var(--accent)}.content{flex:1;padding:1.5rem}.muted{color:var(--muted)}.error-banner{background:#e5484d1f;color:var(--danger);border:1px solid var(--danger);padding:.6rem 1rem;border-radius:8px;margin-bottom:1rem}.success-banner{background:#06c7551f;color:var(--accent-dark);border:1px solid var(--accent);padding:.6rem 1rem;border-radius:8px;margin-top:1rem}.dashboard{display:grid;grid-template-columns:260px 1fr;gap:1rem;height:calc(100vh - 130px)}.user-list{background:var(--panel);border:1px solid var(--border);border-radius:12px;padding:1rem;overflow-y:auto}.user-list h2{font-size:.95rem;margin-top:0}.user-list ul{list-style:none;padding:0;margin:0;display:flex;flex-direction:column;gap:.25rem}.user-list button{width:100%;text-align:left;padding:.6rem .75rem;background:transparent;border:none;border-radius:8px;color:var(--text);cursor:pointer;font-size:.9rem}.user-list button:hover{background:var(--bg)}.user-list button.active{background:var(--accent);color:#fff}.thread{display:flex;flex-direction:column;background:var(--panel);border:1px solid var(--border);border-radius:12px;padding:1rem;overflow:hidden}.messages{flex:1;overflow-y:auto;display:flex;flex-direction:column;gap:.5rem;padding:.5rem}.bubble{max-width:60%;padding:.55rem .85rem;border-radius:14px;display:flex;flex-direction:column;gap:2px}.bubble time{font-size:.65rem;opacity:.6}.bubble.in{align-self:flex-start;background:var(--bg);border:1px solid var(--border)}.bubble.out{align-self:flex-end;background:var(--accent);color:#fff}.reply-box{display:flex;gap:.5rem;margin-top:.75rem}.reply-box input{flex:1;padding:.6rem .85rem;border-radius:999px;border:1px solid var(--border);background:var(--bg);color:var(--text)}button{cursor:pointer;font-family:inherit}.reply-box button,.rule-form button,.broadcast-page button{background:var(--accent);color:#fff;border:none;padding:.6rem 1.2rem;border-radius:999px;font-weight:600}.reply-box button:hover,.rule-form button:hover,.broadcast-page button:hover{background:var(--accent-dark)}button.danger{background:transparent;color:var(--danger);border:1px solid var(--danger);padding:.3rem .75rem;border-radius:6px;font-weight:500}.rules-page{display:grid;grid-template-columns:360px 1fr;gap:1.5rem;align-items:start}.rule-form,.rule-list{background:var(--panel);border:1px solid var(--border);border-radius:12px;padding:1.25rem}.rule-form label{display:flex;flex-direction:column;gap:.35rem;margin-bottom:.85rem;font-size:.85rem;color:var(--muted)}.rule-form input,.rule-form select,.rule-form textarea{padding:.55rem .7rem;border-radius:8px;border:1px solid var(--border);background:var(--bg);color:var(--text);font-family:inherit}table{width:100%;border-collapse:collapse;font-size:.9rem}th,td{text-align:left;padding:.6rem .5rem;border-bottom:1px solid var(--border)}tr.disabled-row{opacity:.5}.broadcast-page{max-width:560px}.broadcast-page textarea{width:100%;padding:.75rem;border-radius:10px;border:1px solid var(--border);background:var(--panel);color:var(--text);font-family:inherit;margin-bottom:.85rem;resize:vertical}