:root {
  --bg: #f8fbff;
  --surface: #ffffff;
  --text: #111827;
  --muted: #475569;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --border: #dbeafe;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  width: min(960px, 92vw);
  margin: 0 auto;
}

.site-header {
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  backdrop-filter: blur(8px);
  background: rgba(255, 255, 255, 0.9);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
}

.brand {
  color: var(--text);
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  gap: 1rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-weight: 500;
}

.nav-links a.active,
.nav-links a:hover {
  color: var(--text);
}

.hero {
  padding: 4rem 0 2rem;
}

.one-page-hero {
  padding-top: 2.5rem;
  padding-bottom: 0.5rem;
}

.tag {
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.hero h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  margin: 0 0 1rem;
}

.hero p {
  color: var(--muted);
  max-width: 60ch;
}

.hero-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.btn {
  border: 1px solid transparent;
  background: var(--primary);
  color: #ffffff;
  padding: 0.6rem 1rem;
  border-radius: 0.55rem;
  font-weight: 700;
  cursor: pointer;
  text-decoration: none;
}

.btn:hover {
  background: var(--primary-dark);
}

.btn.secondary {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}

.btn.secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.page {
  padding: 2.5rem 0;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
  margin: 2rem 0;
}

.card,
.timer-card {
  background: #eff6ff;
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: 1rem;
}

.card p {
  color: var(--muted);
}

.timer-card {
  max-width: 420px;
  margin-top: 1.5rem;
}

.timer-display {
  font-size: 3rem;
  font-weight: 800;
  margin: 0 0 1rem;
  text-align: center;
}

.timer-inputs,
.timer-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

.timer-inputs input {
  width: 90px;
  padding: 0.45rem;
  border-radius: 0.5rem;
  border: 1px solid var(--border);
  background: #ffffff;
  color: var(--text);
}

.social-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1rem;
  margin-top: 1.5rem;
  margin-bottom: 1rem;
}

.social-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 0.85rem;
  padding: 1.1rem;
  text-decoration: none;
  color: var(--text);
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.social-card h2 {
  margin: 0 0 0.45rem;
  font-size: 1.15rem;
}

.social-top {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
}

.social-logo {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

.social-top h2 {
  margin: 0;
}

.social-card p {
  margin: 0 0 0.75rem;
  color: var(--muted);
}

.social-card span {
  color: var(--primary);
  font-weight: 600;
  font-size: 0.95rem;
  word-break: break-word;
}

.social-card:hover {
  transform: translateY(-3px);
  border-color: #bfdbfe;
  box-shadow: 0 10px 20px rgba(37, 99, 235, 0.12);
}

.site-footer {
  margin-top: auto;
  border-top: 1px solid var(--border);
  padding: 1rem 0;
}

.site-footer p {
  color: var(--muted);
  text-align: center;
  margin: 0;
}

@media (max-width: 680px) {
  .nav {
    flex-direction: column;
    gap: 0.75rem;
  }

  .timer-inputs,
  .timer-controls,
  .hero-actions {
    flex-wrap: wrap;
  }
}