/* 由 reference/exploring-space-v6.html 搬過來的樣式（配色、字型、版面）。改外觀請先對照參考檔。 */
:root{
  --ground:#F6F7F9; --surface:#FFFFFF; --ink:#17212B; --muted:#55606E;
  --line:#E2E6EB; --line-soft:#EEF1F4; --chip-line:#D5DDE6;
  --accent:#1D5C8C; --accent-dark:#123E61; --accent-soft:#EAF1F8;
  --learn-bg:#F3F6FA; --module-bg:#E8EEF5;
  --warn-ink:#8A4A12; --warn-bg:#FBF4EC; --tip-ink:#1E6B52; --tip-bg:#EDF7F2; --tip-line:#B8DCCB;
  --on-accent:#FFFFFF; --rail:#9AAABB;
  --fig-sun:#F0B341; --fig-lit:#FFF6DA; --fig-dark:#4A5563; --fig-earth:#3D7FB8;
  --fig-line:#8897A8; --fig-umbra:#2E3742; --fig-pen:#A9B4C1; --fig-text:#3B4552;
  --todo:#C62828; --todo-bg:#FDECEC;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --ground:#12171D; --surface:#1A2129; --ink:#E6EBF0; --muted:#9BA7B4;
    --line:#2A333D; --line-soft:#232B34; --chip-line:#36414D;
    --accent:#7FB3DD; --accent-dark:#A9CDEB; --accent-soft:#1F3347;
    --learn-bg:#1E2630; --module-bg:#22303F;
    --warn-ink:#E8B583; --warn-bg:#2B231B; --tip-ink:#8FD3B6; --tip-bg:#17281F; --tip-line:#2F5444;
    --on-accent:#0E1A26; --rail:#5B6B7C;
    --fig-sun:#E8A92F; --fig-lit:#F3E9C8; --fig-dark:#5A6676; --fig-earth:#4F95CF;
    --fig-line:#6D7C8D; --fig-umbra:#0B0F14; --fig-pen:#4A5562; --fig-text:#C9D2DC; --todo:#FF8A80; --todo-bg:#3A1C1C;
  }
}
:root[data-theme="dark"]{
  --ground:#12171D; --surface:#1A2129; --ink:#E6EBF0; --muted:#9BA7B4;
  --line:#2A333D; --line-soft:#232B34; --chip-line:#36414D;
  --accent:#7FB3DD; --accent-dark:#A9CDEB; --accent-soft:#1F3347;
  --learn-bg:#1E2630; --module-bg:#22303F;
  --warn-ink:#E8B583; --warn-bg:#2B231B; --tip-ink:#8FD3B6; --tip-bg:#17281F; --tip-line:#2F5444;
  --on-accent:#0E1A26; --rail:#5B6B7C;
  --fig-sun:#E8A92F; --fig-lit:#F3E9C8; --fig-dark:#5A6676; --fig-earth:#4F95CF;
  --fig-line:#6D7C8D; --fig-umbra:#0B0F14; --fig-pen:#4A5562; --fig-text:#C9D2DC; --todo:#FF8A80; --todo-bg:#3A1C1C;
}
:root{box-sizing:border-box;padding-top:env(safe-area-inset-top,0px);padding-bottom:env(safe-area-inset-bottom,0px)}
html{scroll-padding-top:calc(env(safe-area-inset-top,0px) + 68px);background:var(--ground)}
*,*::before,*::after{box-sizing:border-box}
body{margin:0;background:var(--ground);color:var(--ink);font-family:'IBM Plex Sans','Noto Sans TC',system-ui,sans-serif;font-size:15px;line-height:1.55}
a{color:var(--accent)} a:hover{color:var(--accent-dark)}
:focus-visible{outline:3px solid var(--accent);outline-offset:2px}
button{font:inherit;cursor:pointer}
h1,h2,h3,h4{margin:0}
p{margin:0}

.topbar{background:var(--surface);border-bottom:1px solid var(--line)}
.topbar-inner{max-width:1120px;margin:0 auto;padding:0 24px;height:64px;display:flex;align-items:center;gap:32px}
.brand{font-weight:700;font-size:18px;color:var(--ink);text-decoration:none}
.back{display:inline-flex;align-items:center;gap:6px;min-height:44px;text-decoration:none;font-weight:600}
main{max-width:1120px;margin:0 auto;padding:32px 24px 64px;display:flex;flex-direction:column;gap:24px}
.course{font-size:13px;font-weight:600;color:var(--muted)}
.book-head h1{font-size:32px;line-height:1.2}
.sub{color:var(--muted)}

/* Terms: blue = has Chinese on hover / tap */
.term{color:var(--accent);font-weight:700;border-bottom:1px dotted var(--accent);cursor:help;border-radius:2px}
.term.open{background:var(--accent-soft)}
b.plain{font-weight:700}
.pop{position:fixed;z-index:50;background:var(--ink);color:var(--surface);font-size:15px;font-weight:500;padding:6px 12px;border-radius:8px;pointer-events:none;opacity:0;transform:translateY(4px);transition:opacity .12s,transform .12s;max-width:260px;font-family:'Noto Sans TC',system-ui,sans-serif}
.pop.show{opacity:1;transform:none}
@media (prefers-reduced-motion: reduce){.pop{transition:none}}

/* Book page */
.col-head,.lesson-row{display:grid;grid-template-columns:minmax(0,2fr) minmax(0,3fr)}
.col-head{gap:12px;padding:0 4px;font-size:13px;font-weight:700;color:var(--muted)}
.module{display:flex;flex-direction:column;gap:8px}
.module-head{background:var(--module-bg);border-radius:10px;padding:10px 12px 10px 20px;display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}
.module-head h2{font-size:18px}
.ov-link{display:inline-flex;align-items:center;gap:6px;min-height:44px;padding:0 16px;border-radius:22px;background:var(--surface);border:1px solid var(--chip-line);text-decoration:none;font-weight:600;font-size:14px}
.lesson-row{background:var(--surface);border:1px solid var(--line);border-radius:10px;overflow:hidden}
.learn{background:var(--learn-bg);padding:18px 20px;display:flex;flex-direction:column;gap:12px;border-right:1px solid var(--line)}
.lesson-no{font-size:13px;color:var(--muted)}
.lesson-name{font-size:17px;font-weight:600}
.lesson-name .term{color:var(--ink);font-weight:600;border-bottom-color:var(--chip-line)}
.tools{display:flex;flex-wrap:wrap;gap:8px}
.tool{display:inline-flex;align-items:center;gap:6px;min-height:44px;padding:0 14px;border-radius:8px;background:var(--surface);border:1px solid var(--chip-line);color:var(--ink);text-decoration:none;font-size:14px;font-weight:500}
.tool:hover{border-color:var(--accent);color:var(--ink)}
.tool svg{stroke:var(--accent)}
.skills{list-style:none;margin:0;padding:8px 0}
.skills li{display:flex;align-items:center;gap:12px;padding:0 20px;min-height:44px}
.skills .num{width:20px;flex-shrink:0;font-size:14px;color:var(--muted);text-align:right}
.skills a{flex-grow:1;text-decoration:none}
.score{min-width:44px;text-align:center;font-size:13px;border-radius:6px;padding:2px 8px;color:var(--muted);border:1px dashed var(--chip-line)}
.pending{color:var(--muted);font-size:14px;padding:12px 20px}
.todo{border:1.5px dashed var(--todo);background:var(--todo-bg);color:var(--todo);border-radius:8px;padding:10px 14px;font-size:14px;font-family:'Noto Sans TC','IBM Plex Sans',system-ui,sans-serif;line-height:1.5}
.todo b{font-weight:700}
.todo .src{display:block;font-size:12.5px;opacity:.85}
.todo-list{display:flex;flex-direction:column;gap:8px}
.skills li.todo-li,.aside li.todo-li{min-height:0;padding-top:4px;padding-bottom:4px;border-bottom:none}
.todo-li span{color:var(--todo);font-size:13px;font-weight:600;font-family:'Noto Sans TC','IBM Plex Sans',system-ui,sans-serif}

/* Overview tree (縱貫線) */
.ov{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:20px;display:flex;flex-direction:column;gap:20px}
.ov-lesson{display:grid;grid-template-columns:44px minmax(0,1fr);gap:16px}
.ov-band{background:var(--accent);color:var(--on-accent);border-radius:22px;display:flex;align-items:center;justify-content:center;padding:16px 0;text-decoration:none}
.ov-band span{writing-mode:vertical-rl;transform:rotate(180deg);font-weight:700;font-size:14px;letter-spacing:.02em;white-space:nowrap}
.ov-band:hover{color:var(--on-accent);background:var(--accent-dark)}
.ov-secs{display:flex;flex-direction:column;gap:12px}
.ov-sec{display:grid;grid-template-columns:168px minmax(0,1fr);gap:0;align-items:center}
.ov-node{display:flex;align-items:center;justify-content:center;text-align:center;min-height:52px;padding:8px 12px;border:1.5px solid var(--accent);border-radius:8px;background:var(--accent-soft);color:var(--accent-dark);font-weight:700;font-size:14px;line-height:1.3;text-decoration:none;position:relative}
.ov-node:hover{background:var(--surface);color:var(--accent-dark)}
.ov-node::after{content:"";position:absolute;right:-18px;top:50%;width:18px;border-top:2px solid var(--rail)}
.ov-leaves{list-style:none;margin:0 0 0 18px;padding:2px 0 2px 16px;border-left:2px solid var(--rail);display:flex;flex-direction:column;gap:6px}
.ov-leaves li{position:relative;font-size:14px;line-height:1.45}
.ov-leaves li::before{content:"";position:absolute;left:-16px;top:.72em;width:10px;border-top:2px solid var(--rail)}
.ov-leaves .k{font-weight:700;color:var(--accent)}
.ov.compact{padding:16px 18px}
.ov-title{font-size:13px;font-weight:700;color:var(--muted)}

/* Lesson page */
.lesson-head h1{font-size:30px;line-height:1.2}
.tabbar{position:sticky;top:0;z-index:20;background:var(--ground);display:flex;align-items:flex-end;justify-content:space-between;gap:12px;border-bottom:1px solid var(--line);padding-top:env(safe-area-inset-top,0px);margin-top:calc(-1 * env(safe-area-inset-top,0px))}
.tabs{display:flex;gap:4px;overflow-x:auto}
.zh-toggle{display:inline-flex;align-items:center;gap:10px;min-height:44px;margin-bottom:4px;padding:0 12px 0 14px;border-radius:22px;border:1px solid var(--chip-line);background:var(--surface);color:var(--ink);font-weight:600;font-size:14px;font-family:'Noto Sans TC','IBM Plex Sans',system-ui,sans-serif;flex-shrink:0}
.zh-toggle .sw{width:34px;height:20px;border-radius:10px;background:var(--chip-line);position:relative;transition:background .15s}
.zh-toggle .sw::after{content:"";position:absolute;left:2px;top:2px;width:16px;height:16px;border-radius:50%;background:var(--surface);transition:transform .15s}
.zh-toggle[aria-pressed="true"]{border-color:var(--accent)}
.zh-toggle[aria-pressed="true"] .sw{background:var(--accent)}
.zh-toggle[aria-pressed="true"] .sw::after{transform:translateX(14px)}
.zh{display:none;font-family:'Noto Sans TC',system-ui,sans-serif;color:var(--muted);font-size:14px;line-height:1.6;font-weight:400;margin-top:2px}
body.zh-on .zh{display:block}
.pt-title .zh{font-size:14px;margin-top:0}
.subsec h3 .zh{display:none}
body.zh-on .subsec h3 .zh{display:inline;margin-left:8px}
.tab{min-height:48px;padding:0 18px;border-bottom:3px solid transparent;color:var(--muted);font-weight:500;text-decoration:none;display:inline-flex;align-items:center}
.tab[aria-selected="true"]{border-bottom-color:var(--accent);color:var(--ink);font-weight:700}
.study-grid{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:24px;align-items:start}
.notes{display:flex;flex-direction:column;gap:16px;min-width:0}

details.pt{background:var(--surface);border:1px solid var(--line);border-radius:12px;overflow:hidden}
details.pt > summary{list-style:none;display:flex;align-items:center;gap:14px;padding:14px 20px;min-height:60px;cursor:pointer}
details.pt > summary::-webkit-details-marker{display:none}
.pt-no{flex-shrink:0;width:34px;height:34px;border-radius:9px;background:var(--accent);color:var(--on-accent);display:flex;align-items:center;justify-content:center;font-weight:700}
.pt-title{font-size:18px;font-weight:700;flex-grow:1}
.chev{flex-shrink:0;transition:transform .15s;stroke:var(--muted)}
details.pt[open] .chev{transform:rotate(180deg)}
.pt-body{padding:4px 24px 24px 68px;display:flex;flex-direction:column;gap:22px;border-top:1px solid var(--line-soft)}
.subsec{display:flex;flex-direction:column;gap:12px;padding-top:18px}
.subsec h3{font-size:16px;display:flex;gap:10px;align-items:baseline}
.subsec h3 .letter{color:var(--accent);font-weight:700}
.subsec.with-fig{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,340px);column-gap:24px;row-gap:12px;align-items:start}
.subsec.with-fig h3{grid-column:1 / -1}
.subsec.with-fig .flow.a{grid-column:1;grid-row:2}
.subsec.with-fig .flow.b{grid-column:1;grid-row:3}
.subsec.with-fig .prac-row{grid-row:4}
.subsec.with-fig figure{grid-column:2;grid-row:2 / span 2}
.flow{display:flex;flex-direction:column;gap:12px;min-width:0}
ol.pts{margin:0;padding-left:22px;display:flex;flex-direction:column;gap:8px}
ol.pts li::marker{color:var(--muted);font-weight:600}
.note{font-size:13.5px;color:var(--muted);display:flex;gap:8px}
.note .lbl{flex-shrink:0;font-weight:700;color:var(--muted);border:1px solid var(--chip-line);border-radius:4px;padding:0 5px;font-size:12px;height:20px;line-height:18px;margin-top:1px}
.qa{background:var(--warn-bg);border-radius:10px;padding:12px 16px}
.qa .lbl{font-size:13px;font-weight:700;color:var(--warn-ink);margin-bottom:4px}
.qa .q{font-weight:600}
.qa details{margin-top:6px}
.qa details summary{cursor:pointer;color:var(--warn-ink);font-weight:600;font-size:14px;min-height:32px;display:inline-flex;align-items:center}
.qa details p{margin-top:4px}
figure{margin:0;background:var(--learn-bg);border-radius:10px;padding:12px}
figure svg{width:100%;height:auto;display:block}
figure.wide svg{margin:0 auto}
figure.wide .f-txt{font-size:11px}
figcaption{font-size:13px;color:var(--muted);margin-top:6px}
.cmp{min-width:0}
.cmp .ttl{font-size:14px;font-weight:700;margin-bottom:8px}
.cmp-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:10px}
.cmp table{border-collapse:collapse;width:100%;min-width:480px;font-size:14px}
.cmp th,.cmp td{padding:9px 12px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line-soft)}
.cmp thead th{background:var(--learn-bg);font-weight:700}
.cmp tbody th{font-weight:600}
.cmp tbody tr:last-child th,.cmp tbody tr:last-child td{border-bottom:none}
.pt-foot{display:flex;flex-wrap:wrap;align-items:center;justify-content:flex-end;gap:12px;border-top:1px dashed var(--line);padding-top:16px}
.prac-row{display:flex;justify-content:flex-end;grid-column:1 / -1}
.prac{display:inline-flex;align-items:center;gap:4px;min-height:40px;padding:0 10px 0 16px;border-radius:20px;background:var(--accent);color:var(--on-accent);text-decoration:none;font-weight:700;font-size:14px}
.prac:hover{background:var(--accent-dark);color:var(--on-accent)}
.prac svg{stroke:currentColor}
.skills li.grp,.aside li.grp{min-height:0;padding-top:12px;padding-bottom:2px;font-size:12.5px;font-weight:700;color:var(--muted);text-transform:none;border-bottom:none}
.skills li.grp:first-child,.aside li.grp:first-child{padding-top:4px}
li.grp .term{color:var(--muted);font-weight:700;border-bottom-color:var(--chip-line)}
.prac-c{display:flex;align-items:center;gap:6px;flex-wrap:wrap}
.prac-c .lbl{font-size:13px;font-weight:700;color:var(--muted);margin-right:4px}
.prac-c a{display:inline-flex;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:0 12px;border-radius:22px;border:1.5px solid var(--accent);color:var(--accent-dark);text-decoration:none;font-weight:700;font-size:14px}
.prac-c a:hover{background:var(--accent);color:var(--on-accent)}
.prac-m{display:none;flex-direction:column;gap:8px;width:100%}
.prac-m a{display:flex;align-items:center;min-height:44px;padding:8px 16px;border-radius:22px;background:var(--accent);color:var(--on-accent);text-decoration:none;font-weight:600;font-size:14px;line-height:1.35}
.next{display:inline-flex;align-items:center;gap:6px;min-height:44px;padding:0 4px 0 16px;border:none;background:none;color:var(--accent);font-weight:700;font-size:14px;text-decoration:none;margin-left:auto}
.next:hover{color:var(--accent-dark)}
.next svg{stroke:currentColor}
details.glance{display:block}
details.glance > summary{list-style:none;cursor:pointer;display:flex;align-items:center;justify-content:space-between;min-height:28px}
details.glance > summary::-webkit-details-marker{display:none}
details.glance[open] > summary{margin-bottom:12px}
details.glance[open] .chev{transform:rotate(180deg)}

.aside{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:18px;display:flex;flex-direction:column;gap:8px;position:sticky;top:72px}
.aside h2{font-size:13px;font-weight:700;color:var(--muted)}
.aside ol{list-style:none;margin:0;padding:0}
.aside li{display:flex;align-items:center;gap:10px;min-height:44px;border-bottom:1px solid var(--line-soft)}
.aside li:last-child{border-bottom:none}
.aside li a{flex-grow:1;text-decoration:none;font-size:14px}
.aside .s{font-size:13px;font-weight:700;color:var(--muted)}

.vocab{list-style:none;margin:0;padding:0;background:var(--surface);border:1px solid var(--line);border-radius:12px}
.vocab li{padding:14px 22px;border-bottom:1px solid var(--line-soft)}
.vocab li:last-child{border-bottom:none}
.vocab .tw{font-size:17px}
.vocab .ex{color:var(--muted)}
.hint{font-size:13px;color:var(--muted)}

/* Figures */
.f-sun{fill:var(--fig-sun)} .f-lit{fill:var(--fig-lit)} .f-dark{fill:var(--fig-dark)}
.f-earth{fill:var(--fig-earth)} .f-line{stroke:var(--fig-line);fill:none}
.f-umbra{fill:var(--fig-umbra)} .f-pen{fill:var(--fig-pen);opacity:.55}
.f-txt{fill:var(--fig-text);font-family:'IBM Plex Sans',system-ui,sans-serif;font-size:15px}
.f-txt.b{font-weight:700}
.f-axis{stroke:var(--fig-text);stroke-width:1.6}
.f-ray{stroke:var(--fig-sun);stroke-width:2;fill:none}

@media (max-width:900px){
  .study-grid{grid-template-columns:minmax(0,1fr)}
  .aside{position:static}
  .subsec.with-fig{display:flex;flex-direction:column}
}
@media (max-width:720px){
  .lesson-row{grid-template-columns:minmax(0,1fr)}
  .learn{border-right:none;border-bottom:1px solid var(--line)}
  .col-head{display:none}
  .book-head h1{font-size:26px}
  main{padding:20px 16px 32px}
  .pt-body{padding:4px 16px 20px}
  details.pt > summary{padding:12px 16px}
  .ov{padding:14px}
  .ov-lesson{grid-template-columns:minmax(0,1fr);gap:10px}
  .ov-band{padding:10px 16px;justify-content:flex-start}
  .ov-band span{writing-mode:horizontal-tb;transform:none}
  .ov-sec{grid-template-columns:minmax(0,1fr);gap:8px}
  .ov-node{justify-content:flex-start;text-align:left;min-height:44px}
  .ov-node::after{display:none}
  .ov-leaves{margin-left:14px}
  .lesson-head h1{font-size:26px}
  .prac-c{display:none}
  .prac-m{display:flex}
  .next{margin-left:0;padding-left:0}
  .zh-toggle{padding:0 10px}
}

/* ===== 以下是 v6 原型沒有、網站另外需要的樣式（沿用 v6 的顏色變數） ===== */
.topbar-inner .zh-toggle{margin-left:auto;margin-bottom:0}
.zh-toggle.htmx-request{opacity:.6}
.site-foot{max-width:1120px;margin:0 auto;padding:20px 24px 40px;border-top:1px solid var(--line);font-size:12.5px;color:var(--muted);font-family:'Noto Sans TC','IBM Plex Sans',system-ui,sans-serif;line-height:1.6}
.zh-inline{font-family:'Noto Sans TC',system-ui,sans-serif;color:var(--muted);font-weight:400}

/* 練習功能（階段 3）尚未開放：停用狀態 */
.prac.is-disabled,.prac.is-disabled:hover{background:var(--chip-line);color:var(--muted);cursor:not-allowed}
.skills .prac-off{flex-grow:1;color:var(--ink)}
.aside li a .n{color:var(--muted)}

/* 首頁 */
.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:16px}
.card{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:18px 20px;display:flex;flex-direction:column;gap:10px}
.card h3{font-size:17px}
.chips{display:flex;flex-wrap:wrap;gap:6px}
.chip{font-size:12.5px;font-weight:600;padding:2px 10px;border-radius:12px;background:var(--accent-soft);color:var(--accent-dark)}
.card ul{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:4px}
.card li a{display:inline-flex;align-items:center;min-height:36px;font-weight:600;text-decoration:none}
.empty{color:var(--muted)}
.notice{background:var(--warn-bg);color:var(--warn-ink);border-radius:10px;padding:12px 16px}
.section-title{font-size:20px}

/* 技能頁 */
.skill-body{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:4px 24px 24px}
@media (max-width:720px){.skill-body{padding:4px 16px 20px}.site-foot{padding:16px 16px 32px}}
.module-head .term,.ov-band .term{color:inherit;border-bottom-color:var(--chip-line)}
.module-head h2 .zh,.lesson-name .zh,.lesson-head h1 .zh{font-size:14px}
.brand{white-space:nowrap;flex-shrink:0}
.back{min-width:0}
.back span{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
@media (max-width:720px){.topbar-inner{padding:0 16px;gap:16px}}

/* ---------- 階段 2：帳號、設定、家長／家教頁（沿用 v6 的配色與字型） ---------- */
.acct{display:flex;align-items:center;gap:14px;font-size:14px;font-weight:600;flex-wrap:wrap}
.acct a{text-decoration:none}
.acct form{margin:0}
.topbar-inner .acct{margin-left:auto}
.topbar-inner .zh-toggle + .acct,.topbar-inner .zh-locked + .acct{margin-left:0}
.linkish{background:none;border:0;padding:0;color:var(--accent);font-weight:600;font-size:14px}
.role-switch{display:inline-flex;gap:4px}
.chip-btn{border:1px solid var(--chip-line);background:var(--surface);color:var(--ink);border-radius:16px;padding:4px 12px;font-size:13px;font-weight:600}
.chip-btn[aria-pressed="true"]{background:var(--accent);border-color:var(--accent);color:var(--on-accent)}
.zh-locked{margin-left:auto;font-size:13px;color:var(--muted);max-width:280px}
.messages{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:8px}
.msg{border-radius:10px;padding:12px 16px;background:var(--tip-bg);color:var(--tip-ink);border:1px solid var(--tip-line)}
.msg.error{background:var(--todo-bg);color:var(--todo);border-color:var(--todo)}
.panel{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:20px 24px;display:flex;flex-direction:column;gap:12px}
.panel.narrow{max-width:480px;width:100%;margin:0 auto}
.panel h1{font-size:26px}
.panel h2{font-size:19px}
.panel h3{font-size:15px;margin-top:6px}
.panel form{display:flex;flex-direction:column;gap:12px;margin:0}
.panel form.inline,.panel form.row-actions{flex-direction:row;align-items:center;flex-wrap:wrap;gap:8px}
.panel form.inline-form{flex-direction:row;align-items:flex-end;flex-wrap:wrap;gap:10px}
.field{display:flex;flex-direction:column;gap:4px;border:0;margin:0;padding:0}
.field label,.field legend{font-weight:600;font-size:14px}
.field input,.field select,.field textarea,.panel select,.redeem input{font:inherit;padding:10px 12px;border:1px solid var(--chip-line);border-radius:8px;background:var(--surface);color:var(--ink);min-height:44px}
.field textarea{min-height:100px}
.field .opt,.help{color:var(--muted);font-size:13px;font-weight:400}
.radio,.check{display:flex;align-items:flex-start;gap:8px;font-weight:400 !important;font-size:14px;min-height:32px}
.radio input,.check input{min-height:auto;margin-top:4px}
.err,.form-errors{color:var(--todo);font-size:13px}
.form-errors{background:var(--todo-bg);border-radius:8px;padding:10px 12px}
.has-error input{border-color:var(--todo)}
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:0 18px;border-radius:22px;border:1px solid var(--accent);background:var(--accent);color:var(--on-accent);font-weight:600;text-decoration:none;font-size:15px}
.btn:hover{color:var(--on-accent);background:var(--accent-dark)}
.btn-secondary{background:var(--surface);color:var(--accent)}
.btn-secondary:hover{background:var(--accent-soft);color:var(--accent-dark)}
.btn-danger{background:var(--todo);border-color:var(--todo)}
.btn-small{min-height:34px;padding:0 12px;font-size:13px}
.btn-block{width:100%}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.links{font-size:14px;color:var(--muted)}
.or{display:flex;align-items:center;gap:10px;color:var(--muted);font-size:13px}
.or::before,.or::after{content:"";flex:1;border-top:1px solid var(--line)}
table.simple{border-collapse:collapse;width:100%;font-size:14px}
table.simple th,table.simple td{text-align:left;padding:8px 10px;border-bottom:1px solid var(--line-soft);vertical-align:middle}
table.simple th{color:var(--muted);font-weight:600;font-size:13px}
.badge{display:inline-block;padding:2px 10px;border-radius:12px;font-size:12px;font-weight:600;background:var(--line-soft);color:var(--muted)}
.badge.ok{background:var(--tip-bg);color:var(--tip-ink)}
.code-box{display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.code-box .code{font-family:ui-monospace,Menlo,monospace;font-size:26px;font-weight:700;letter-spacing:4px;color:var(--accent)}
.redeem input[name="code"]{font-family:ui-monospace,Menlo,monospace;letter-spacing:1px}
.outline-lessons{margin:0;padding-left:20px;display:flex;flex-direction:column;gap:8px}
.outline-point{margin:4px 0 0 4px;color:var(--muted);font-size:14px}
.outline-point ul{margin:2px 0 0;padding-left:18px;color:var(--ink)}
.foot-links{display:block;margin-top:6px}
@media (max-width:640px){
  .topbar-inner{gap:12px;flex-wrap:wrap;height:auto;min-height:64px;padding-top:8px;padding-bottom:8px}
  .panel{padding:16px}
}