:root {
  --bg: #f8fafc;
  --surface: #ffffff;
  --text: #0f172a;
  --muted: #64748b;
  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --border: #e2e8f0;
  --shadow: 0 10px 40px rgba(15, 23, 42, 0.08);
}

[data-theme="dark"] {
  --bg: #0b1120;
  --surface: #111827;
  --text: #f8fafc;
  --muted: #94a3b8;
  --accent: #818cf8;
  --accent-hover: #a5b4fc;
  --border: #1e293b;
  --shadow: 0 10px 40px rgba(0, 0, 0, 0.35);
}

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

body {
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background 0.3s, color 0.3s;
}

a {
  color: inherit;
  text-decoration: none;
}

.header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(12px);
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  border-bottom: 1px solid var(--border);
}

.nav {
  max-width: 960px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  font-weight: 700;
  font-size: 1.125rem;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}

.nav-links a:hover {
  color: var(--accent);
}

.theme-toggle {
  border: 1px solid var(--border);
  background: var(--surface);
  border-radius: 999px;
  width: 2.5rem;
  height: 2.5rem;
  cursor: pointer;
  font-size: 1rem;
}

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.5rem 4rem;
}

.hero {
  text-align: center;
  padding: 5rem 0 4rem;
}

.badge {
  display: inline-block;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  background: color-mix(in srgb, var(--accent) 15%, transparent);
  color: var(--accent);
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 1.25rem;
}

.hero h1 {
  font-size: clamp(2.5rem, 6vw, 4rem);
  line-height: 1.1;
  margin-bottom: 1rem;
}

.subtitle {
  color: var(--muted);
  font-size: 1.125rem;
  max-width: 32rem;
  margin: 0 auto 2rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.25rem;
  border-radius: 0.75rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform 0.15s, background 0.2s;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--accent);
  color: white;
}

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

.btn-secondary {
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.click-count {
  color: var(--muted);
  font-size: 0.95rem;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.25rem;
  margin-bottom: 4rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1rem;
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

.card-icon {
  font-size: 1.75rem;
  display: block;
  margin-bottom: 0.75rem;
}

.card h2 {
  margin-bottom: 0.5rem;
  font-size: 1.125rem;
}

.card p {
  color: var(--muted);
  font-size: 0.95rem;
}

.contact {
  max-width: 32rem;
  margin: 0 auto;
}

.contact h2 {
  text-align: center;
  margin-bottom: 1.5rem;
}

.contact-form {
  display: grid;
  gap: 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1rem;
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

.contact-form label {
  display: grid;
  gap: 0.4rem;
  font-weight: 600;
  font-size: 0.9rem;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 0.75rem 0.9rem;
  border-radius: 0.6rem;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font: inherit;
}

.form-status {
  text-align: center;
  margin-top: 1rem;
  color: var(--accent);
  font-weight: 600;
}

.messages-section {
  margin-bottom: 4rem;
}

.messages-section h2 {
  text-align: center;
  margin-bottom: 1.5rem;
}

.messages-list {
  display: grid;
  gap: 1rem;
}

.message-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1rem;
  padding: 1.25rem;
  box-shadow: var(--shadow);
}

.message-card strong {
  display: block;
  margin-bottom: 0.25rem;
  color: var(--accent);
}

.message-card p {
  color: var(--text);
  margin-bottom: 0.5rem;
}

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

.muted {
  color: var(--muted);
  text-align: center;
}

.footer {
  text-align: center;
  padding: 2rem 1.5rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.9rem;
}

@media (max-width: 600px) {
  .nav-links {
    display: none;
  }
}