/* 產品網站共用樣式：跟隨瀏覽器淺色／深色模式 */
:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --surface: #f1f3f4;
  --card: #ffffff;
  --border: #dadce0;
  --text: #202124;
  --muted: #5f6368;
  --primary: #1a73e8;
  --on-primary: #ffffff;
  --radius: 12px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #202124;
    --surface: #18191b;
    --card: #2d2e31;
    --border: #3c4043;
    --text: #e8eaed;
    --muted: #9aa0a6;
    --primary: #8ab4f8;
    --on-primary: #202124;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--surface);
  color: var(--text);
  font: 16px/1.7 'Segoe UI', 'Microsoft JhengHei', system-ui, sans-serif;
}
a { color: var(--primary); }
.wrap { max-width: 860px; margin: 0 auto; padding: 0 20px; }

/* 頂端列：標誌、頁面連結、語言切換 */
.top { background: var(--bg); border-bottom: 1px solid var(--border); }
.top .wrap { display: flex; align-items: center; gap: 16px; height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; color: var(--text); text-decoration: none; flex: 1; }
.brand img { width: 30px; height: 30px; }
.top nav a { color: var(--muted); text-decoration: none; font-size: 14px; }
.top nav a:hover { color: var(--text); }
.lang-switch button {
  font: inherit; font-size: 13px; padding: 2px 10px; border-radius: 999px; cursor: pointer;
  border: 1px solid var(--border); background: transparent; color: var(--muted);
}
.lang-switch button.on { background: var(--primary); color: var(--on-primary); border-color: transparent; }

/* 依語言顯示：<html data-lang="zh"> 時只顯示 .zh，en 時只顯示 .en */
html[data-lang='zh'] .en, html[data-lang='en'] .zh { display: none !important; }

/* 首頁 */
.hero { text-align: center; padding: 64px 0 40px; }
.hero img { width: 88px; height: 88px; }
.hero h1 { margin: 16px 0 8px; font-size: 34px; }
.hero p { margin: 0 auto; max-width: 560px; color: var(--muted); font-size: 18px; }
.button {
  display: inline-block; margin-top: 24px; padding: 10px 26px; border-radius: 999px;
  background: var(--primary); color: var(--on-primary); text-decoration: none; font-weight: 600;
}
.button.disabled { opacity: 0.6; pointer-events: none; }

section.card { background: var(--card); border-radius: var(--radius); padding: 24px 28px; margin: 20px 0; }
section.card h2 { margin-top: 0; font-size: 22px; }
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; padding: 0; list-style: none; }
.features li { background: var(--surface); border-radius: 10px; padding: 14px 16px; }
.features b { display: block; margin-bottom: 4px; }

table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); vertical-align: top; }
th { color: var(--muted); font-weight: 600; }

/* 條款、政策頁 */
.doc h1 { font-size: 28px; margin: 40px 0 4px; }
.doc .updated { color: var(--muted); font-size: 14px; margin-bottom: 24px; }
.doc h2 { font-size: 20px; margin-top: 32px; }
.doc li { margin: 4px 0; }

footer { color: var(--muted); font-size: 14px; text-align: center; padding: 32px 0 48px; }
footer a { color: var(--muted); margin: 0 8px; }