:root {
  --primary-color: #2563eb;
  --secondary-color: #3b82f6;
  --background: #f9fafb; /* softer than white */
  --text-color: #111827;
  --card-bg: #ffffff;
  --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  --border-radius: 14px;
  --transition-time: 0.3s;
  --font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  font-family: var(--font-family);
  line-height: 1.7;
  color: var(--text-color);
  background-color: var(--background);
  margin: 0;
  padding-top: 75px;
}

.navbar {
  backdrop-filter: blur(12px);
  background-color: rgba(255, 255, 255, 0.95);
  position: fixed;
  top: 0;
  width: 100%;
  padding: 1rem 3rem;
  box-shadow: var(--shadow);
  z-index: 150;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 2rem;
  margin: 0;
  padding: 0;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-color);
  font-weight: 600;
  font-size: 1rem;
  transition: color var(--transition-time);
}

.nav-links a:hover,
.nav-links a:focus {
  color: var(--primary-color);
  outline: none;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.hero-section {
  background: linear-gradient(135deg, #e0e7ff, #f0f4ff);
  padding: 120px 1rem 80px;
  text-align: center;
  border-radius: var(--border-radius);
  max-width: 900px;
  margin: 2rem auto;
  box-shadow: var(--shadow);
}

.hero-content h1 {
  font-size: 3rem;
  margin-bottom: 0.4rem;
  color: var(--primary-color);
}

.hero-content p {
  font-size: 1.25rem;
  color: #374151;
  margin-bottom: 1.5rem;
}

.btn-primary {
  background-color: var(--primary-color);
  color: white;
  padding: 0.85rem 2rem;
  border: none;
  border-radius: var(--border-radius);
  font-size: 1.1rem;
  cursor: pointer;
  transition: background-color var(--transition-time), transform var(--transition-time);
}

.btn-primary:hover,
.btn-primary:focus {
  background-color: var(--secondary-color);
  transform: translateY(-3px);
  outline: none;
}

section {
  max-width: 900px;
  margin: 3rem auto;
  padding: 0 1rem;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--primary-color);
  border-bottom: 3px solid var(--secondary-color);
  display: inline-block;
  padding-bottom: 0.2rem;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 1.5rem;
}

.skill-category {
  background-color: var(--card-bg);
  padding: 1rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  text-align: center;
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--primary-color);
  transition: transform var(--transition-time);
}
.skill-category:hover {
  transform: scale(1.05);
}

.project-card {
  background-color: var(--card-bg);
  padding: 1.75rem 1.5rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  transition: transform var(--transition-time), box-shadow var(--transition-time);
  margin-bottom: 2rem;
}

.project-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 12px 22px rgba(37, 99, 235, 0.15);
}

.project-card h3 {
  margin-top: 0;
  color: var(--primary-color);
  font-weight: 700;
}

.project-card p {
  color: #4b5563;
  line-height: 1.5;
}

.timeline {
  max-width: 750px;
  margin: 0 auto 4rem;
  position: relative;
}

.timeline-item {
  background-color: var(--card-bg);
  margin: 1.5rem 0;
  padding: 1.5rem 2rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  transition: box-shadow var(--transition-time);
}

.timeline-item:hover {
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.15);
}

form {
  max-width: 480px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
}

input, textarea {
  padding: 0.9rem 1rem;
  font-size: 1rem;
  border-radius: var(--border-radius);
  border: 1.5px solid #e5e7eb;
  margin-bottom: 1rem;
  transition: border-color var(--transition-time);
}

input:focus, textarea:focus {
  border-color: var(--primary-color);
  outline: none;
  box-shadow: 0 0 6px rgba(37, 99, 235, 0.4);
}

@media (max-width: 768px) {
  .nav-links {
    flex-direction: column;
    gap: 1rem;
  }
  .hero-content h1 {
    font-size: 2.2rem;
  }
  .section-title {
    font-size: 1.75rem;
  }
  .skills-grid {
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  }
}