/* 1.01 Academy — 清爽科技風（精簡版） */
:root {
  --bg: #f6f8fc;
  --card: #ffffff;
  --soft: #eef2f9;
  --text: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --primary: #4f46e5;
  --ok: #059669;
  --grad: linear-gradient(135deg, #06b6d4, #4f46e5 60%, #7c3aed);
  --grid: rgba(79, 70, 229, .06);
  --radius: 14px;
  --font: 'Inter', 'Noto Sans TC', system-ui, -apple-system, 'PingFang TC', 'Microsoft JhengHei', sans-serif;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme='light']) {
    --bg: #070b16; --card: #0e1424; --soft: #151d32; --text: #e6ebf5; --muted: #94a3b8;
    --border: #1e2a42; --primary: #818cf8; --ok: #34d399; --grid: rgba(129, 140, 248, .07); color-scheme: dark;
  }
}
:root[data-theme='dark'] {
  --bg: #070b16; --card: #0e1424; --soft: #151d32; --text: #e6ebf5; --muted: #94a3b8;
  --border: #1e2a42; --primary: #818cf8; --ok: #34d399; --grid: rgba(129, 140, 248, .07); color-scheme: dark;
}

* { box-sizing: border-box; }
body { margin: 0; font-family: var(--font); background: var(--bg); color: var(--text); line-height: 1.6; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
h1 { font-size: clamp(26px, 4vw, 36px); line-height: 1.25; margin: 24px 0 8px; }
h2 { font-size: 20px; margin: 32px 0 12px; }
h3 { font-size: 16px; margin: 6px 0; line-height: 1.4; }
.container { max-width: 1100px; margin: 0 auto; padding: 0 16px; }
.narrow { max-width: 460px; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.center { text-align: center; }
.pad { padding: 16px 18px; }
.grad { background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.row-between { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }

/* 按鈕與表單 */
.btn { display: inline-flex; align-items: center; justify-content: center; height: 44px; padding: 0 20px; border: 0; border-radius: 10px; background: var(--grad); color: #fff; font: inherit; font-weight: 600; cursor: pointer; transition: transform .15s; box-shadow: 0 6px 18px -8px rgba(79, 70, 229, .6); }
.btn:hover { transform: translateY(-1px); }
.btn:disabled { opacity: .6; cursor: wait; }
.btn-sm { height: 36px; padding: 0 14px; font-size: 14px; }
.btn-block { width: 100%; }
.btn-ghost { background: var(--soft); color: var(--text); box-shadow: none; }
.link { background: none; border: 0; padding: 0; font: inherit; color: var(--primary); cursor: pointer; }
.input { width: 100%; height: 44px; margin-top: 6px; padding: 0 14px; border: 1px solid var(--border); border-radius: 10px; background: var(--card); color: var(--text); font: inherit; }
.input:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 4px rgba(79, 70, 229, .12); }
label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 14px; }
.two { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
form.card, .narrow > .card { margin-bottom: 16px; }

/* 頁首 */
header { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--bg) 85%, transparent); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; gap: 12px; }
.nav nav { display: flex; align-items: center; gap: 16px; font-size: 14px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; }
.logo-mark { width: 32px; height: 32px; border-radius: 9px; background: var(--grad); color: #fff; display: grid; place-items: center; font: 700 11px 'JetBrains Mono', monospace; }
.icon-btn { display: grid; place-items: center; width: 36px; height: 36px; border-radius: 9px; border: 1px solid var(--border); background: var(--card); color: var(--text); cursor: pointer; font-size: 16px; }
@media (max-width: 520px) { .logo { font-size: 0; gap: 0; } .nav nav { gap: 12px; } }

/* 首頁 */
.hero { position: relative; padding: 56px 0 32px; text-align: center; overflow: hidden; }
.hero::before { content: ''; position: absolute; inset: 0; background-image: linear-gradient(var(--grid) 1px, transparent 1px), linear-gradient(90deg, var(--grid) 1px, transparent 1px); background-size: 40px 40px; mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%); -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%); }
.hero .container { position: relative; }
.hero h1 { font-size: clamp(30px, 5.5vw, 52px); font-weight: 900; letter-spacing: -.02em; }
.search { max-width: 420px; margin-top: 16px; }
.chips { display: flex; gap: 8px; flex-wrap: wrap; margin: 8px 0 20px; }
.chip { height: 34px; padding: 0 14px; border-radius: 999px; border: 1px solid var(--border); background: var(--card); color: var(--muted); font: inherit; font-size: 14px; cursor: pointer; }
.chip.active { background: var(--text); color: var(--bg); border-color: var(--text); }

/* 卡片 */
.card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 20px; margin-bottom: 40px; }
.course { transition: transform .2s, box-shadow .2s; }
.course:hover { transform: translateY(-3px); box-shadow: 0 18px 36px -18px rgba(15, 23, 42, .35); }
.thumb { aspect-ratio: 16 / 9; display: grid; place-items: center; color: #fff; position: relative; }
.thumb::before { content: ''; position: absolute; inset: 0; background-image: linear-gradient(rgba(255,255,255,.1) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.1) 1px, transparent 1px); background-size: 22px 22px; }
.thumb span { position: relative; font: 700 38px 'JetBrains Mono', monospace; }
.tag { font-size: 12px; color: var(--primary); font-weight: 600; }
.price { font: 700 18px 'JetBrains Mono', monospace; }
.price.free { color: var(--ok); font-family: var(--font); }
.owned { color: var(--ok); font-weight: 600; font-size: 14px; }

/* 課程頁 */
.course-page { display: grid; grid-template-columns: 1fr 320px; gap: 40px; padding-top: 24px; padding-bottom: 48px; align-items: start; }
.course-page .lead { font-size: 17px; }
.buy { position: sticky; top: 84px; }
.checks { padding: 0; list-style: none; display: grid; gap: 8px; }
.checks li::before { content: '✓  '; color: var(--ok); font-weight: 700; }
.chapter { padding: 14px 18px; margin-bottom: 10px; }
.lesson { display: flex; justify-content: space-between; gap: 12px; padding: 8px 0; border-top: 1px solid var(--border); font-size: 14px; margin-top: 8px; }
@media (max-width: 820px) { .course-page { grid-template-columns: 1fr; } .buy { position: static; order: -1; } }

/* 上課頁 */
.player { display: grid; grid-template-columns: 1fr 320px; min-height: calc(100vh - 65px); }
.player h2 { margin: 4px 0 16px; }
.side { border-left: 1px solid var(--border); background: var(--card); }
.side-ch { padding: 10px 18px; font-size: 12px; font-weight: 700; color: var(--muted); background: var(--soft); }
.side-l { display: flex; align-items: center; gap: 10px; padding: 12px 18px; font-size: 14px; border-left: 3px solid transparent; }
.side-l .small { margin-left: auto; }
.side-l:hover { background: var(--soft); }
.side-l.active { border-left-color: var(--primary); background: var(--soft); font-weight: 600; }
.dot { width: 18px; height: 18px; flex: none; border-radius: 50%; border: 2px solid var(--border); display: grid; place-items: center; font-size: 11px; color: #fff; }
.dot.done { background: var(--ok); border-color: var(--ok); }
.bar { height: 6px; border-radius: 9px; background: var(--soft); overflow: hidden; margin: 10px 0 4px; }
.bar i { display: block; height: 100%; background: var(--grad); }
@media (max-width: 820px) { .player { grid-template-columns: 1fr; } .side { border-left: 0; border-top: 1px solid var(--border); } }

/* 提示 */
.toast { position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%); z-index: 60; padding: 12px 18px; border-radius: 10px; background: var(--text); color: var(--bg); font-size: 14px; box-shadow: 0 12px 30px -10px rgba(0, 0, 0, .4); }
.footer { padding: 32px 16px; border-top: 1px solid var(--border); margin-top: 40px; }

/* 登入與影片 */
.btn-google { gap: 10px; background: var(--card); color: var(--text); border: 1px solid var(--border); box-shadow: none; }
.divider { display: flex; align-items: center; gap: 12px; margin: 18px 0; color: var(--muted); font-size: 13px; }
.divider::before, .divider::after { content: ''; flex: 1; height: 1px; background: var(--border); }
.notice { padding: 12px 14px; border-radius: 10px; background: var(--soft); font-size: 14px; margin-bottom: 10px; }
.user-name { max-width: 140px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.video { position: relative; aspect-ratio: 16 / 9; background: #000; border-radius: var(--radius); overflow: hidden; }
.player .video { border-radius: 0; }
.video iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.video.empty { display: grid; place-items: center; color: #94a3b8; }
code { font-family: 'JetBrains Mono', monospace; font-size: .9em; background: var(--soft); padding: 1px 6px; border-radius: 6px; }
@media (max-width: 520px) { .user-name { display: none; } }
[hidden] { display: none !important; }

/* 上課頁：單元資訊在影片上方、說明在影片下方 */
.lesson-head { display: flex; justify-content: space-between; align-items: flex-end; gap: 12px; flex-wrap: wrap; }
.lesson-head h2 { margin: 2px 0 0; }
.lesson-head p { margin: 0; }
.lesson-nav { display: flex; gap: 8px; flex-wrap: wrap; }
.lesson-note { border-top: 1px solid var(--border); line-height: 1.8; }
.lesson-note h3 { margin: 0 0 8px; }

/* 管理者：課程編輯 */
.thumb img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.textarea { height: auto; padding: 10px 14px; line-height: 1.6; resize: vertical; }
.check { display: flex; align-items: center; gap: 8px; font-weight: 500; }
.check input { width: 18px; height: 18px; accent-color: var(--primary); }
.notice-card { margin-bottom: 20px; border-color: var(--primary); }
.admin-list { display: grid; gap: 14px; margin: 20px 0 40px; }
.admin-row { display: grid; grid-template-columns: 200px 1fr; align-items: center; }
.admin-row .pad p { margin: 4px 0 10px; }
.editor { max-width: 860px; padding-bottom: 48px; }
.editor .card { margin-bottom: 18px; }
.editor h3 { margin: 0 0 14px; }
.cover-edit { display: grid; grid-template-columns: 280px 1fr; gap: 20px; align-items: start; }
.cover-preview { border-radius: var(--radius); overflow: hidden; border: 1px solid var(--border); }
.ed-chapter { border: 1px solid var(--border); border-radius: var(--radius); padding: 14px; margin-bottom: 14px; background: var(--soft); }
.ed-chapter > .row-between .input { flex: 1; margin-top: 0; }
.ed-lesson { background: var(--card); border: 1px solid var(--border); border-radius: 10px; padding: 12px 14px; margin: 12px 0; }
.ed-lesson label { margin-bottom: 10px; }
.editor-actions { display: flex; gap: 12px; justify-content: space-between; }
@media (max-width: 640px) {
  .admin-row, .cover-edit { grid-template-columns: 1fr; }
}

/* 常見問題與說明頁 */
.home-faq { margin-bottom: 24px; }
.faq { display: grid; gap: 10px; }
.faq details { padding: 0 18px; }
.faq summary { cursor: pointer; padding: 14px 0; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: '+'; color: var(--muted); font-size: 18px; line-height: 1; }
.faq details[open] summary::after { content: '−'; color: var(--primary); }
.faq-a { padding: 0 0 16px; color: var(--muted); line-height: 1.8; }
.info-page { max-width: 760px; padding-bottom: 32px; }
.info-page h2 { font-size: 18px; margin: 28px 0 8px; }
.info-page p { line-height: 1.9; }
.info-page .faq { margin-top: 16px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 20px; margin-bottom: 8px; }
.footer-links a:hover { color: var(--primary); }
.footer p { margin: 0; }

/* 管理者：學生開通 */
.admin-tabs { margin-top: 24px; }
.admin-tabs .chip { display: inline-flex; align-items: center; }
.student { margin-bottom: 12px; }
.student .check { margin: 8px 0; }
.search-small { max-width: 240px; margin-top: 0; }

/* 限時免費 */
.free-until { display: block; margin-top: 4px; font-size: 12px; font-weight: 600; color: #dc2626; }
.free-window { border: 1px dashed var(--border); border-radius: 10px; padding: 12px 14px 2px; margin: 4px 0 14px; }
.free-window p { margin: 4px 0 10px; }

/* 上課頁：請勿分享提醒 */
.share-warning { margin: 0; padding-top: 10px; padding-bottom: 10px; font-size: 13px; color: var(--muted); background: var(--soft); border-bottom: 1px solid var(--border); }

/* 管理者：上傳影片 */
.upload-row { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin: -2px 0 12px; }
.upload-row .btn { cursor: pointer; }
.video video { position: absolute; inset: 0; width: 100%; height: 100%; background: #000; }

/* 線上付款：訂單 */
.order-info { display: grid; grid-template-columns: 80px 1fr; gap: 6px 12px; margin: 0 0 14px; font-size: 14px; }
.order-info dt { color: var(--muted); }
.order-info dd { margin: 0; word-break: break-all; }
.table-wrap { overflow-x: auto; }
table.orders { width: 100%; border-collapse: collapse; }
table.orders th, table.orders td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); white-space: nowrap; }
table.orders th { font-size: 12px; color: var(--muted); background: var(--soft); }
.mono { font-family: 'JetBrains Mono', ui-monospace, monospace; }

/* 觀看期限 */
.expired { color: #dc2626; font-weight: 600; }
.grant-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; border-bottom: 1px dashed var(--border); padding: 4px 0; }
.grant-row .check { margin: 6px 0; }
.grant-exp { display: flex; align-items: center; gap: 8px; margin: 0; font-weight: 500; }
.grant-exp .input { width: auto; height: 36px; margin: 0; }