:root {
  --indigo: #5856d6;
  --peach: #ff958c;
  --pink: #ff2d55;
  --bg: #f7f6fb;
  --card: #ffffff;
  --text: #1c1b29;
  --muted: #6b6a7b;
  --border: rgba(28, 27, 41, 0.08);
  --radius: 20px;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111018;
    --card: #1c1b26;
    --text: #f2f1f8;
    --muted: #a3a1b5;
    --border: rgba(255, 255, 255, 0.08);
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Hiragino Sans GB",
    "Helvetica Neue", "Microsoft YaHei", sans-serif;
}

a { color: var(--indigo); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: 960px; margin: 0 auto; padding: 0 16px; }

/* Header */
.nav {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 0;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); font-weight: 700; font-size: 18px; }
.brand img { width: 32px; height: 32px; border-radius: 8px; }
.nav-links { display: flex; align-items: center; gap: 16px; font-size: 15px; }
.nav-links a { color: var(--muted); }
.lang-select {
  appearance: none; -webkit-appearance: none;
  border: 1px solid var(--border); background: var(--card); color: var(--text);
  border-radius: 999px; padding: 5px 30px 5px 12px; font: inherit; font-size: 14px; cursor: pointer;
  background-image: linear-gradient(45deg, transparent 50%, var(--muted) 50%), linear-gradient(135deg, var(--muted) 50%, transparent 50%);
  background-position: calc(100% - 15px) 55%, calc(100% - 10px) 55%;
  background-size: 5px 5px; background-repeat: no-repeat;
}
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0;
}
.translation-note {
  font-size: 14px; color: var(--muted); background: var(--card); border: 1px solid var(--border);
  border-radius: 12px; padding: 10px 14px;
}

/* Hero */
.hero {
  margin-top: 8px;
  border-radius: 28px;
  padding: 56px 24px;
  text-align: center;
  color: #fff;
  background: linear-gradient(160deg, var(--indigo), var(--peach));
}
.hero img { width: 112px; height: 112px; border-radius: 26px; box-shadow: 0 12px 32px rgba(0, 0, 0, 0.25); }
.hero h1 { font-size: clamp(34px, 7vw, 54px); line-height: 1.1; margin: 20px 0 8px; letter-spacing: -0.02em; }
.hero p { font-size: clamp(17px, 3vw, 20px); max-width: 560px; margin: 0 auto; opacity: 0.95; }
.badge {
  display: inline-block; margin-top: 28px; padding: 12px 22px; border-radius: 14px;
  background: rgba(0, 0, 0, 0.85); color: #fff; font-weight: 600;
}

/* Sections */
section { margin: 56px 0; }
h2 { font-size: clamp(26px, 5vw, 34px); line-height: 1.2; margin: 0 0 8px; letter-spacing: -0.01em; }
.lead { color: var(--muted); margin: 0 0 24px; }

.grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 22px;
}
.card .emoji { font-size: 28px; }
.card h3 { margin: 10px 0 4px; font-size: 18px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }

.privacy-callout {
  display: flex; gap: 18px; align-items: flex-start;
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px;
}
.privacy-callout .emoji { font-size: 36px; line-height: 1; }
.privacy-callout p { margin: 4px 0 0; color: var(--muted); }

/* Document pages (privacy, support) */
.doc { max-width: 720px; margin: 24px auto 64px; }
.doc h1 { font-size: clamp(30px, 6vw, 40px); line-height: 1.15; margin: 16px 0 4px; }
.doc .updated { color: var(--muted); font-size: 15px; margin: 0 0 32px; }
.doc h2 { font-size: 22px; margin: 32px 0 8px; }
.doc ul { padding-left: 22px; }
.doc li { margin: 6px 0; }

details {
  background: var(--card); border: 1px solid var(--border); border-radius: 16px;
  padding: 16px 20px; margin: 12px 0;
}
summary { cursor: pointer; font-weight: 600; }
details[open] summary { margin-bottom: 8px; }
details p, details ol, details ul { color: var(--muted); margin: 8px 0 0; }

.contact {
  margin-top: 32px; padding: 24px; border-radius: var(--radius); color: #fff;
  background: linear-gradient(160deg, var(--indigo), var(--peach));
}
.contact a { color: #fff; font-weight: 600; text-decoration: underline; }

/* Footer */
footer {
  border-top: 1px solid var(--border); padding: 24px 0 40px; color: var(--muted); font-size: 14px;
  display: flex; flex-wrap: wrap; gap: 8px 20px; justify-content: space-between;
}
footer nav { display: flex; gap: 16px; }
footer a { color: var(--muted); }

@media (max-width: 520px) {
  .nav-links a.hide-sm { display: none; }
  .hero { padding: 44px 18px; border-radius: 22px; }
  .privacy-callout { flex-direction: column; }
}