*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #F9FFF8;
  --text: #000000;
  --text-secondary: #282A35;
  --text-muted: #888;
  --border: #e0e0e0;
  --btn-bg: #FFFFFF;
  --btn-text: #282A35;
  --btn-border: #d0d0d0;
  --btn-active-bg: #000000;
  --btn-active-text: #FFFFFF;
  --btn-hover-bg: #f0f0f0;
  --link: #2563eb;
  --footer-text: #999;
}

[data-theme="dark"] {
  --bg: #282A35;
  --text: #F9FFF8;
  --text-secondary: #A2A2A2;
  --text-muted: #777;
  --border: #393D49;
  --btn-bg: #393D49;
  --btn-text: #A2A2A2;
  --btn-border: #4a4e5a;
  --btn-active-bg: #F9FFF8;
  --btn-active-text: #282A35;
  --btn-hover-bg: #444857;
  --link: #60a5fa;
  --footer-text: #666;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  transition: background 0.2s, color 0.2s;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 32px 20px 64px;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 40px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
}

.logo {
  font-size: 28px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.5px;
}

.logo-accent {
  color: #41A135;
}

.controls {
  display: flex;
  align-items: center;
  gap: 12px;
}

.theme-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--btn-border);
  border-radius: 6px;
  background: var(--btn-bg);
  color: var(--btn-text);
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}

.theme-btn:hover {
  background: var(--btn-hover-bg);
}

.icon-moon { display: none; }

[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: block; }

.lang-switcher {
  display: flex;
  gap: 0;
  border: 1px solid var(--btn-border);
  border-radius: 6px;
  overflow: hidden;
}

.lang-btn {
  padding: 6px 14px;
  border: none;
  background: var(--btn-bg);
  color: var(--btn-text);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}

.lang-btn:not(:last-child) {
  border-right: 1px solid var(--btn-border);
}

.lang-btn.active {
  background: var(--btn-active-bg);
  color: var(--btn-active-text);
}

.lang-btn:hover:not(.active) {
  background: var(--btn-hover-bg);
}

.updated {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 32px;
}

h1 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 8px;
  letter-spacing: -0.5px;
}

h2 {
  font-size: 20px;
  font-weight: 700;
  margin-top: 36px;
  margin-bottom: 12px;
  color: var(--text);
}

h3 {
  font-size: 16px;
  font-weight: 600;
  margin-top: 20px;
  margin-bottom: 8px;
  margin-left: 16px;
  color: var(--text-secondary);
}

h3 + ul {
  margin-left: 32px;
}

p {
  margin-bottom: 12px;
  color: var(--text-secondary);
}

ul {
  margin-bottom: 12px;
  padding-left: 24px;
  margin-left: 16px;
}

li {
  margin-bottom: 6px;
  color: var(--text-secondary);
}

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

a:hover {
  text-decoration: underline;
}

footer {
  margin-top: 48px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--footer-text);
  text-align: center;
}

@media (max-width: 480px) {
  .container { padding: 20px 16px 48px; }
  h1 { font-size: 24px; }
  h2 { font-size: 18px; }
  header { flex-wrap: wrap; gap: 12px; }
}