:root {
  --accent: #3b82f6;
  --bg: #ffffff;
  --text: #1e1e1e;
  --light: #f9fafb;
}

body.dark-mode {
  --accent: #60a5fa;
  --bg: #0f172a;
  --text: #f1f5f9;
  --light: #1e293b;
}

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

body {
  font-family: 'Inter', sans-serif;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.6;
  scroll-behavior: smooth;
  overflow-x: hidden;
  transition: background 0.4s ease, color 0.4s ease;
}

.container {
  width: 90%;
  max-width: 900px;
  margin: 0 auto;
}

.section {
  padding: 80px 0;
}

.section.alt {
  background-color: var(--light);
  transition: background 0.4s ease;
}

h1, h2, h3, h4 {
  font-weight: 700;
  margin-bottom: 15px;
}

.hero {
  text-align: center;
  padding: 140px 20px 100px;
  background: linear-gradient(135deg, var(--accent) 0%, #2563eb 100%);
  color: white;
  transition: background 0.4s ease;
}

.hero h1 {
  font-size: 2.8rem;
}

.hero h2 {
  font-size: 1.4rem;
  font-weight: 500;
}

.hero p {
  margin-top: 20px;
  font-size: 1.1rem;
}

.hero-buttons {
  margin-top: 30px;
}

.btn {
  display: inline-block;
  padding: 10px 20px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  transition: 0.3s;
}

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

.btn.primary:hover {
  background: #f1f5f9;
}

.btn.secondary {
  border: 2px solid white;
  color: white;
  margin-left: 10px;
}

.btn.secondary:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* Navbar */
.navbar {
  background-color: var(--light);
  padding: 15px 0;
  position: sticky;
  top: 0;
  z-index: 10;
  transition: background 0.4s ease;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-links a {
  color: var(--text);
  text-decoration: none;
  margin: 0 12px;
  font-weight: 600;
  transition: color 0.3s ease;
}

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

/* Theme toggle */
#theme-toggle {
  background: none;
  border: none;
  font-size: 1.3rem;
  cursor: pointer;
  color: var(--text);
  transition: color 0.3s ease;
}

#theme-toggle:hover {
  color: var(--accent);
}

/* Lists, skills, contact */
.experience-list {
  list-style: none;
}

.experience-list li {
  margin-bottom: 25px;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 10px;
}

.skills-grid span {
  background-color: var(--light);
  padding: 10px 15px;
  border-radius: 8px;
  text-align: center;
  font-weight: 600;
  transition: background 0.4s ease;
}

.contact-list {
  list-style: none;
  padding: 0;
}

.contact-list li {
  margin: 10px 0;
}

.contact-list a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
}

footer {
  text-align: center;
  padding: 30px 0;
  background-color: var(--light);
  font-size: 0.9rem;
  transition: background 0.4s ease;
}

/* Animations */
.hidden {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.show {
  opacity: 1;
  transform: translateY(0);
}

.fade-in {
  animation: fadeIn 1s ease-out forwards;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 2rem; }
  .hero h2 { font-size: 1.1rem; }
  .nav-links {
    flex-wrap: wrap;
    text-align: center;
  }
}