:root {
  color-scheme: light dark;
  --bg: #f7f7f5;
  --surface: #ffffff;
  --text: #1c1c1a;
  --muted: #5f5f5a;
  --line: #e4e4df;
  --accent: #2f6f4f;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #151514;
    --surface: #1f1f1d;
    --text: #ededea;
    --muted: #a3a39d;
    --line: #33332f;
    --accent: #7cc39b;
  }
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  -webkit-text-size-adjust: 100%;
}

header,
main,
footer {
  width: 100%;
  max-width: 640px;
  margin: 0 auto;
  padding-left: 16px;
  padding-right: 16px;
}

header {
  padding-top: 24px;
}

.brand {
  color: var(--text);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: 0.01em;
  text-decoration: none;
}

main {
  flex: 1;
  padding-top: 15vh;
  padding-bottom: 48px;
}

h1 {
  margin: 0 0 12px;
  font-size: 26px;
  font-weight: 600;
  line-height: 1.35;
}

p {
  margin: 0 0 12px;
  color: var(--muted);
}

a {
  color: var(--accent);
}

.actions {
  margin-top: 28px;
}

.button {
  display: inline-block;
  padding: 9px 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--text);
  font-size: 15px;
  text-decoration: none;
}

.button:hover {
  border-color: var(--muted);
}

footer {
  padding-bottom: 24px;
  color: var(--muted);
  font-size: 13px;
}

/* 分隔线画在内容区里，与正文左右对齐，不伸进两侧 16px 的留白。 */
footer::before {
  content: "";
  display: block;
  height: 1px;
  margin-bottom: 20px;
  background: var(--line);
}

footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 16px;
  margin-bottom: 6px;
}

footer a {
  color: var(--muted);
  text-decoration: none;
}

footer a:hover {
  color: var(--text);
  text-decoration: underline;
}