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

:root {
  --bg: #f5f7fb;
  --text: #111827;
  --card: #ffffff;
  --accent: #2563eb;
}

body.dark {
  --bg: #0f172a;
  --text: #f8fafc;
  --card: #1e293b;
  --accent: #60a5fa;
}

body {
  font-family: Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: 0.3s;
}

.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 8%;
  background: var(--card);
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  position: sticky;
  top: 0;
}

.logo {
  font-size: 22px;
  font-weight: bold;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 20px;
}

.nav-links a {
  text-decoration: none;
  color: var(--text);
  font-weight: 600;
}

#themeToggle {
  border: none;
  background: var(--accent);
  color: white;
  padding: 10px 14px;
  border-radius: 8px;
  cursor: pointer;
}

.hero {
  text-align: center;
  padding: 100px 20px;
}

.hero h1 {
  font-size: 48px;
  margin-bottom: 15px;
}

.hero p {
  max-width: 650px;
  margin: auto;
  margin-bottom: 30px;
}

.btn {
  display: inline-block;
  padding: 14px 24px;
  background: var(--accent);
  color: white;
  text-decoration: none;
  border-radius: 10px;
}

.section {
  padding: 70px 8%;
  text-align: center;
}

.section h2 {
  margin-bottom: 20px;
  font-size: 32px;
}

.contact-card {
  background: var(--card);
  padding: 25px;
  max-width: 400px;
  margin: auto;
  border-radius: 14px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

footer {
  text-align: center;
  padding: 25px;
  background: var(--card);
  margin-top: 40px;
}

@media (max-width: 768px) {

  .navbar {
    flex-direction: column;
    gap: 15px;
  }

  .hero h1 {
    font-size: 34px;
  }

}