:root {
  --bg: #ffffff;
  --surface: #ffffff;
  --surface-soft: #f4f7ff;
  --text: #222831;
  --muted: #6b7280;
  --line: #d8d8d8;
  --accent: #2a82d7;
  --accent-dark: #3f85b5;
  --danger: #c62828;
  --success: #1b7f3b;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: #ffffff;
  color: var(--text);
}

.page-shell {
  width: min(100%, 390px);
  margin: 0 auto;
  background: #ffffff;
  min-height: 100vh;
}

.site-header {
  background: #d9d9d9;
}

.brand-row {
  display: block;
  padding: 10px 16px 14px;
}

.site-title {
  display: inline-block;
  font-size: 52px;
  line-height: 1;
  color: #2280ff;
  text-decoration: none;
  margin-bottom: 18px;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
}

.site-nav a {
  color: #2280ff;
  text-decoration: none;
  font-size: 20px;
}

.content {
  padding-bottom: 28px;
}

.auth-shell {
  background: #ffffff;
}

.auth-tabs {
  display: none;
}

.auth-single-card {
  background: #ffffff;
}

.auth-status-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 10px 16px 0;
}

.auth-summary {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}

.ghost-button {
  border: 1px solid #cfd6df;
  background: #ffffff;
  color: #5b6574;
  border-radius: 8px;
  padding: 8px 10px;
  font-size: 13px;
}

.ghost-button:disabled {
  opacity: 0.5;
}

.auth-pane {
  display: none;
  padding: 18px 0 0;
}

.auth-pane.active {
  display: block;
}

.auth-pane h1 {
  margin: 0;
  padding: 0 16px 10px;
  font-size: 60px;
  line-height: 1.05;
  font-weight: 500;
  color: #20242d;
  border-bottom: 1px solid #d8d8d8;
}

.auth-form-compact {
  display: grid;
  gap: 28px;
  padding: 22px 0 0;
}

.auth-form label {
  display: grid;
  gap: 10px;
  padding: 0 16px;
}

.auth-form label span {
  font-size: 18px;
  font-weight: 700;
  color: #1f2937;
}

.auth-form input {
  width: 100%;
  height: 62px;
  padding: 0 14px;
  border: 2px solid #d2d2d2;
  border-radius: 7px;
  background: #eaf1ff;
  font-size: 20px;
  color: #1f2937;
  outline: none;
}

.auth-form input:focus {
  border-color: #91b9eb;
}

.primary-button {
  margin: 8px 16px 0;
  width: 210px;
  height: 58px;
  border: none;
  border-radius: 12px;
  background: var(--accent-dark);
  color: #ffffff;
  font-size: 18px;
  cursor: pointer;
}

.form-message {
  min-height: 28px;
  margin: 10px 16px 0;
  font-size: 14px;
}

.form-message.error {
  color: var(--danger);
}

.form-message.success {
  color: var(--success);
}

.post-list {
  display: grid;
  gap: 14px;
  padding: 18px 16px 0;
}

.post-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 16px 18px;
}

.post-card h2 {
  margin: 8px 0 10px;
  font-size: 24px;
  line-height: 1.3;
  font-weight: 700;
}

.post-card p {
  margin: 0;
  color: #333333;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  color: var(--muted);
  font-size: 13px;
}

.tag {
  color: var(--accent);
}

.post-intro {
  margin-bottom: 12px;
}

.number-groups {
  display: grid;
  gap: 4px;
  margin: 14px 0 16px;
  font-family: "Cascadia Code", Consolas, monospace;
}

.sub-list {
  display: grid;
  gap: 12px;
}

.sub-list strong {
  display: inline-block;
  margin-bottom: 3px;
  font-size: 14px;
}