:root {
  --bg: #0f172a;
  --bg-soft: #1e293b;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --primary: #38bdf8;
  --card: #111827;
}

body.light {
  --bg: #f8fafc;
  --bg-soft: #e2e8f0;
  --text: #0f172a;
  --muted: #475569;
  --primary: #0284c7;
  --card: #ffffff;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  font-family: Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  scroll-behavior: smooth;
}

.container {
  width: min(1100px, 92%);
  margin: 0 auto;
}

.hero {
  background: linear-gradient(130deg, var(--bg-soft), var(--bg));
  padding: 1.2rem 0 4rem;
}

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

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

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

#theme-toggle {
  background: transparent;
  border: 1px solid var(--muted);
  color: var(--text);
  border-radius: 8px;
  padding: 0.4rem 0.6rem;
  cursor: pointer;
}

.hero-content {
  margin-top: 3rem;
  max-width: 700px;
}

.badge {
  display: inline-block;
  padding: 0.3rem 0.7rem;
  border-radius: 99px;
  background: rgba(56, 189, 248, 0.15);
  color: var(--primary);
}

.btn {
  display: inline-block;
  background: var(--primary);
  color: white;
  padding: 0.7rem 1rem;
  border: none;
  border-radius: 10px;
  text-decoration: none;
  cursor: pointer;
}

.section {
  padding: 3rem 0;
}

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

.card {
  background: var(--card);
  border: 1px solid var(--bg-soft);
  padding: 1rem;
  border-radius: 12px;
}

.card a {
  color: var(--primary);
  text-decoration: none;
}

form {
  display: grid;
  gap: 0.8rem;
  max-width: 550px;
}

input, textarea {
  width: 100%;
  margin-top: 0.35rem;
  padding: 0.65rem;
  border-radius: 8px;
  border: 1px solid var(--muted);
  background: transparent;
  color: var(--text);
}

footer {
  border-top: 1px solid var(--bg-soft);
  padding: 1.2rem;
  text-align: center;
  color: var(--muted);
}