:root {
  --bg: #0b1020;
  --panel: #121933;
  --text: #e6e8ef;
  --muted: #a7acc0;
  --accent: #7aa2ff;
  --accent-2: #a7ffcf;
  --border: #263055;
  --shadow: rgba(0, 0, 0, 0.25);
}

:root[data-theme="light"] {
  --bg: #f5f7ff;
  --panel: #ffffff;
  --text: #1a233a;
  --muted: #5b6280;
  --accent: #2f58ff;
  --accent-2: #0946c5;
  --border: #d7dcf5;
  --shadow: rgba(15, 23, 42, 0.16);
}

* { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, "Helvetica Neue", Arial, "Apple Color Emoji", "Segoe UI Emoji";
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background 180ms ease, color 180ms ease;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 40px 20px 80px;
}

.header {
  text-align: center;
  margin-bottom: 28px;
  position: relative;
  padding-top: 16px;
}

.title {
  margin: 0 0 6px;
  font-size: 32px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.subtitle {
  margin: 0;
  color: var(--muted);
}

.theme-toggle {
  position: absolute;
  top: 0;
  right: 0;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 6px 16px;
  background: var(--panel);
  color: var(--text);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 12px 24px var(--shadow);
  transition: background 160ms ease, border-color 160ms ease, transform 160ms ease, color 160ms ease;
}

.theme-toggle:hover {
  background: color-mix(in srgb, var(--accent) 14%, var(--panel));
  border-color: color-mix(in oklab, var(--accent) 45%, var(--border));
  transform: translateY(-1px);
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.links {
  display: grid;
  grid-template-columns: repeat(1, minmax(0, 1fr));
  gap: 24px;
}

.section {
  display: flex;
  flex-direction: column;
  gap: 16px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 24px;
  box-shadow: 0 20px 40px rgba(3, 6, 15, 0.55);
}

.section-title {
  margin: 0;
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.01em;
}

@media (min-width: 640px) {
  .links { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1024px) {
  .links { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

.card {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.02));
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 18px 16px;
  color: inherit;
  text-decoration: none;
  position: relative;
  box-shadow: 0 8px 20px var(--shadow);
  transition: transform 140ms ease, background 140ms ease, border-color 140ms ease;
  margin: 0;
}

.card a {
  color: inherit;
  text-decoration: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.card:hover {
  transform: translateY(-2px);
  border-color: color-mix(in oklab, var(--accent) 60%, var(--border));
  background: linear-gradient(180deg, rgba(122,162,255,0.12), rgba(122,162,255,0.04));
}

.card-title {
  font-weight: 700;
  font-size: 18px;
}

.card-desc {
  color: var(--muted);
  font-size: 14px;
}

.footer {
  text-align: center;
  margin-top: 40px;
  color: var(--muted);
  font-size: 14px;
}

.github-link {
  color: var(--accent);
  text-decoration: none;
  font-size: 13px;
  font-weight: 500;
  margin-top: 4px;
  display: block;
}

.github-link:hover {
  color: var(--accent-2);
  text-decoration: underline;
}

.github-link.private {
  color: var(--muted);
}

.github-link.private:hover {
  color: var(--text);
}