:root {
  --primary: #1e4d8c;
  --primary-dark: #153a6a;
  --accent: #2c7be5;
  --text: #222;
  --muted: #555;
  --bg: #f8f9fa;
  --white: #fff;
  --border: #e0e4e8;
}

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

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

header {
  background: var(--primary);
  color: white;
  padding: 2.5rem 0 1.5rem;
  text-align: center;
}

header h1 {
  font-size: 2.4rem;
  font-weight: 600;
  letter-spacing: -0.5px;
}

.subtitle {
  font-size: 1.15rem;
  opacity: 0.9;
  margin-top: 0.3rem;
}

nav {
  background: var(--primary-dark);
  position: sticky;
  top: 0;
  z-index: 10;
}

nav .container {
  display: flex;
  justify-content: center;
  gap: 2rem;
  padding: 0.8rem 1.5rem;
}

nav a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
}

nav a:hover {
  text-decoration: underline;
}

section {
  padding: 3.5rem 0;
  background: white;
}

section:nth-child(even) {
  background: var(--bg);
}

h2 {
  color: var(--primary);
  font-size: 1.8rem;
  margin-bottom: 1.5rem;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
  padding-bottom: 0.3rem;
}

.hero p {
  font-size: 1.05rem;
  margin-bottom: 1rem;
  color: var(--muted);
}

.experience {
  margin-bottom: 2.2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.experience:last-child {
  border-bottom: none;
}

.experience h3 {
  color: var(--primary);
  font-size: 1.25rem;
  margin-bottom: 0.2rem;
}

.period {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 0.8rem;
  font-style: italic;
}

.experience ul {
  padding-left: 1.3rem;
}

.experience li {
  margin-bottom: 0.4rem;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
  margin: 1.5rem 0 2.5rem;
}

.skill {
  background: white;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.3rem;
  box-shadow: 0 2px 6px rgba(0,0,0,0.04);
}

.skill h3 {
  color: var(--primary);
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  max-width: 600px;
  margin-top: 1.5rem;
}

.contact-form label {
  font-weight: 500;
  font-size: 0.95rem;
}

.contact-form input,
.contact-form textarea {
  padding: 0.7rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 1rem;
  font-family: inherit;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(44,123,229,0.15);
}

.contact-form button {
  background: var(--primary);
  color: white;
  border: none;
  padding: 0.85rem 1.5rem;
  border-radius: 6px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  margin-top: 0.5rem;
  align-self: flex-start;
}

.contact-form button:hover {
  background: var(--primary-dark);
}

.form-note {
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 1.2rem;
}

footer {
  background: var(--primary-dark);
  color: white;
  text-align: center;
  padding: 1.5rem 0;
  font-size: 0.9rem;
}

@media (max-width: 600px) {
  header h1 { font-size: 1.9rem; }
  nav .container { gap: 1.2rem; flex-wrap: wrap; }
  section { padding: 2.5rem 0; }
}