:root{--bg:#fbfaf7;--card:#fff;--ink:#2b2a28;--mute:#6f6b64;--line:#e6e2d9;--accent:#d9644a;--accent2:#f3d9d0;--ok:#3f7d58;--warn:#b6711c}
:root[data-theme=dark]{--bg:#17181a;--card:#212325;--ink:#ecebe7;--mute:#a09c94;--line:#34363a;--accent:#f08a70;--accent2:#4a2f28;--ok:#7bc496;--warn:#e0a458}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.65 -apple-system,"PingFang TC","Noto Sans TC",sans-serif}
a{color:inherit}
.top{position:sticky;top:0;z-index:5;display:flex;gap:14px;align-items:center;padding:10px 16px;background:var(--bg);border-bottom:1px solid var(--line);flex-wrap:wrap}
.brand{font-weight:700;text-decoration:none;font-size:18px}.brand span{color:var(--accent);margin-left:6px;font-weight:600}
nav{display:flex;gap:4px;flex-wrap:wrap}nav a{padding:4px 10px;border-radius:999px;text-decoration:none;color:var(--mute);font-size:15px}
nav a.on{background:var(--accent2);color:var(--ink)}
#searchForm{margin-left:auto;flex:1;max-width:340px;min-width:180px}
#q{width:100%;padding:8px 14px;border:1px solid var(--line);border-radius:999px;background:var(--card);color:var(--ink);font-size:16px}
.icon{width:34px;height:34px;border-radius:50%;border:1px solid var(--line);background:var(--card);color:var(--ink);cursor:pointer;font-size:15px}
main{max-width:1180px;margin:0 auto;padding:20px 16px 40px;min-height:70vh}
h1{font-size:24px;margin:6px 0 14px}h2{font-size:18px;margin:26px 0 10px}
.filters{display:flex;gap:8px;flex-wrap:wrap;align-items:center;margin-bottom:16px}
.chip,.sel{border:1px solid var(--line);background:var(--card);color:var(--ink);border-radius:999px;padding:5px 13px;font-size:14px;cursor:pointer}
.chip.on{background:var(--accent);border-color:var(--accent);color:#fff}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:18px}
.card{background:var(--card);border:1px solid var(--line);border-radius:12px;overflow:hidden;position:relative;display:flex;flex-direction:column}
.card.sel-on{outline:3px solid var(--accent)}
.card a.thumb{position:relative;display:block;aspect-ratio:16/9;background:#ddd}
.card img{width:100%;height:100%;object-fit:cover;display:block}
.dur{position:absolute;right:6px;bottom:6px;background:rgba(0,0,0,.78);color:#fff;font-size:12px;padding:1px 6px;border-radius:4px}
.card .b{padding:10px 12px 12px;display:flex;flex-direction:column;gap:4px;flex:1}
.card .t{font-weight:600;line-height:1.4;text-decoration:none}
.meta{color:var(--mute);font-size:13px}
.tags{display:flex;gap:6px;flex-wrap:wrap;margin-top:2px}
.tag{font-size:12px;padding:1px 8px;border-radius:999px;background:var(--accent2)}
.tag.safe{background:#f6e3c6;color:#7a4a05}:root[data-theme=dark] .tag.safe{background:#4a3a1c;color:#f0c27a}
.acts{position:absolute;top:6px;left:6px;display:flex;gap:6px;opacity:0;transition:.15s}.card:hover .acts,.card.sel-on .acts,.card:focus-within .acts{opacity:1}
.acts button{border:0;border-radius:50%;width:30px;height:30px;background:rgba(0,0,0,.7);color:#fff;cursor:pointer;font-size:14px}.acts button.on{background:var(--accent)}
.empty{color:var(--mute);padding:40px 0;text-align:center}
.player{position:relative;aspect-ratio:16/9;max-width:860px;background:#000;border-radius:12px;overflow:hidden}.player iframe{position:absolute;inset:0;width:100%;height:100%;border:0}
.vwrap{display:grid;grid-template-columns:minmax(0,1fr);gap:20px}
.btns{display:flex;gap:8px;flex-wrap:wrap;margin:12px 0}.btn{border:1px solid var(--line);background:var(--card);color:var(--ink);padding:6px 14px;border-radius:999px;cursor:pointer;font-size:14px;text-decoration:none}.btn.on{background:var(--accent);color:#fff;border-color:var(--accent)}
ul.sum{padding-left:20px}ul.sum li{margin:6px 0}
ol.pts{list-style:none;padding:0;margin:0;max-width:860px}ol.pts li{display:flex;gap:10px;padding:8px 0;border-bottom:1px solid var(--line)}
.ts{flex:none;border:0;background:var(--accent2);color:var(--ink);border-radius:6px;padding:2px 10px;cursor:pointer;font-variant-numeric:tabular-nums;height:28px}
.note{background:var(--accent2);border-radius:10px;padding:10px 14px;font-size:14px;margin:12px 0;max-width:860px}
.cats{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:14px}.cat{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:16px;text-decoration:none}.cat b{display:block;font-size:17px}.cat span{color:var(--mute);font-size:14px}
footer{max-width:1180px;margin:20px auto 0;padding:0 16px 36px}
footer .thanks{display:flex;flex-direction:column;gap:6px;align-items:center;text-align:center;background:var(--accent2);border-radius:14px;padding:18px 20px;line-height:1.7}
footer .thanks b{font-size:17px}footer .thanks span{max-width:640px}
footer .fine{margin-top:18px;text-align:center;color:var(--mute);font-size:13px}footer .fine p{margin:4px auto;max-width:720px}
footer .fine a{color:var(--mute);text-underline-offset:3px}footer .fine i{font-style:normal;margin:0 6px}
dialog{border:1px solid var(--line);border-radius:12px;background:var(--card);color:var(--ink);max-width:420px}dialog::backdrop{background:rgba(0,0,0,.45)}
dl{display:grid;grid-template-columns:90px 1fr;gap:6px 10px}dt{font-weight:700;font-variant-numeric:tabular-nums}dd{margin:0}

.about{max-width:720px;margin:0 auto}.about p,.about li{line-height:1.9}.about ul.sum{padding-left:22px}.about a{color:var(--accent)}
nav a.about-link{background:var(--accent);color:#fff;font-weight:600}nav a.about-link.on{background:var(--accent);color:#fff;box-shadow:0 0 0 2px var(--accent2)}
body{line-break:strict;word-break:auto-phrase;text-wrap:pretty}h1,h2,.card .t{text-wrap:balance}
.nb{white-space:nowrap}
h2[id]{scroll-margin-top:84px}
.why{font-size:17px;margin:2px 0 8px;max-width:860px}
.ours{background:var(--accent2);border-radius:12px;padding:12px 16px;margin:16px 0;max-width:860px}.ours b{display:block;margin-bottom:4px}.ours ul{margin:0;padding-left:20px}.ours li{margin:4px 0}
.stats{display:flex;gap:28px;flex-wrap:wrap;margin:6px 0 18px}.stats div{display:flex;flex-direction:column}.stats b{font-size:34px;line-height:1.1;color:var(--accent)}.stats span{color:var(--mute);font-size:14px}

/* ---- 2026-11-03 改版：學 HackerTube，選項收起來、一路往下滑都是影片 ---- */
.top{flex-wrap:nowrap;gap:10px;padding:10px 16px;position:sticky}
.brand{white-space:nowrap}.brand span{display:none}
.menu{display:none}
#searchForm{display:flex;flex:1;max-width:380px;min-width:0;margin-left:auto}
#q{flex:1;min-width:0;border-radius:999px 0 0 999px;border-right:0;padding:8px 14px}
.sbtn{border:1px solid var(--line);background:var(--card);color:var(--ink);border-radius:0 999px 999px 0;padding:0 14px;cursor:pointer;display:inline-flex;align-items:center}
.icon{display:inline-flex;align-items:center;justify-content:center;flex:none}
nav{display:none}
body.menu-open nav{display:flex;position:absolute;top:100%;left:0;right:0;flex-direction:column;gap:4px;background:var(--bg);border-bottom:1px solid var(--line);padding:8px 12px 14px;box-shadow:0 10px 20px rgba(0,0,0,.12)}
nav a{padding:13px 14px;font-size:16px;border-radius:10px}
nav a.about-link{text-align:center;margin-top:6px}
.menu{display:inline-flex}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.bar{display:flex;align-items:center;gap:12px;margin:2px 0 14px}
.fbtn{display:inline-flex;gap:8px;align-items:center;border:1px solid var(--line);background:var(--card);color:var(--ink);border-radius:999px;padding:9px 18px;font-size:16px;cursor:pointer}
.fbtn.has{border-color:var(--accent);color:var(--accent)}
.fpanel{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:12px;margin-bottom:18px}
.fpanel .filters{margin-bottom:10px}.fpanel .filters:last-child{margin-bottom:0}
.grid{grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:26px 20px}
.card{background:none;border:0;border-radius:0;overflow:visible}
.card a.thumb{border-radius:12px;overflow:hidden}
.card .b{padding:10px 2px 0;gap:3px}.card .t{font-size:17px;font-weight:600}
.tag.safe{margin-left:8px}
.acts{top:8px;left:8px}
.sel{font-size:16px;padding:8px 14px}.chip{padding:8px 14px}
@media(hover:none){.acts{opacity:1}}
@media(min-width:520px){.brand span{display:inline}}
@media(max-width:640px){
  .top{padding:8px 12px;gap:8px}.icon{width:40px;height:40px}
  main{padding:12px 12px 28px}h1{font-size:20px;line-height:1.45}h2{font-size:17px}
  .grid{grid-template-columns:1fr;gap:24px}
  .ts{height:36px;min-width:52px}.btn{padding:9px 16px}
  footer .thanks{padding:16px 14px}
}

/* ---- 左側選單（學 HackerTube）：所有功能收在 ☰，說明收在 ? ---- */
.menu{display:inline-flex}
#side{position:fixed;top:var(--hh,57px);left:0;bottom:0;width:230px;padding:8px 10px 24px;background:var(--bg);overflow-y:auto;z-index:6;display:flex;flex-direction:column;gap:2px;transform:translateX(-102%);transition:transform .18s}
#side a{display:flex;align-items:center;gap:16px;padding:11px 14px;border-radius:12px;text-decoration:none;font-size:15px;color:var(--ink);border:2px solid transparent}
#side a:hover{background:var(--accent2)}
#side a.on{background:var(--accent2);border-color:var(--accent)}
.sidefoot{margin-top:18px;padding:14px 14px 0;border-top:1px solid var(--line);display:flex;flex-direction:column;gap:6px}
.sidefoot a{padding:4px 0;gap:0;font-size:13px;color:var(--mute);border:0;border-radius:0;text-decoration:underline;text-underline-offset:3px}
#scrim{display:none;position:fixed;inset:0;background:rgba(0,0,0,.45);z-index:5}
body.menu-open #side{transform:none;top:0;padding-top:14px;box-shadow:0 0 30px rgba(0,0,0,.35)}
body.menu-open #scrim{display:block}
body.feed footer{display:none}
@media(min-width:900px){
  #side{transform:none}body.side-collapsed #side{transform:translateX(-102%)}
  body:not(.side-collapsed){padding-left:230px}
  body.menu-open #side{top:var(--hh,57px);padding-top:8px;box-shadow:none}body.menu-open #scrim{display:none}
}
body.video footer .thanks{display:none}