/*
 * Global styles for JhonJA one‑page portfolio
 *
 * This stylesheet defines a simple responsive layout
 * using modern CSS (flexbox and media queries). It sets
 * a clean typographic baseline and colours consistent with
 * a professional portfolio. Each section is separated by
 * generous padding to improve readability on all screen sizes.
 */

html {
  box-sizing: border-box;
  scroll-behavior: smooth;
}

*, *::before, *::after {
  box-sizing: inherit;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
    Helvetica, Arial, sans-serif;
  line-height: 1.6;
  color: #222;
  background: #f7f7f7;
}

header {
  background: #869FA1;
  color: #fff;
  text-align: center;
  padding: 2rem 1rem;
  position: relative;
}

header h1 {
  margin: 0;
  font-size: 2.2rem;
  letter-spacing: 0.5px;
}

header p {
  margin: 0.5rem 0 0;
  font-size: 1rem;
  font-weight: 300;
}

nav {
  margin-top: 1rem;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
}

nav a {
  color: #f7f7f7;
  text-decoration: none;
  font-weight: 600;
  padding: 0.5rem;
  transition: color 0.2s ease;
}

nav a:hover {
  color: #dde8f3;
}

main {
  padding: 2rem 1rem;
  max-width: 900px;
  margin: 0 auto;
}

section {
  margin-bottom: 3rem;
}

section h2 {
  margin-top: 0;
  margin-bottom: 1rem;
  color: #869FA1;
  border-bottom: 2px solid #0a3c7d;
  display: inline-block;
  padding-bottom: 0.25rem;
}

article {
  margin-bottom: 2rem;
}

article h3 {
  margin: 0 0 0.3rem;
  font-size: 1.1rem;
  color: #869FA1;
}

article p {
  margin: 0.2rem 0;
}

/* Lists of skills or certifications */
.list-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
}

.list-grid span {
  background: #f0f4f8;
  padding: 0.3rem 0.6rem;
  border-radius: 0.25rem;
  font-size: 0.9rem;
}

footer {
  background: #f6f6f6;
  padding: 1rem;
  text-align: center;
  font-size: 0.85rem;
  color: #555;
}

@media (min-width: 768px) {
  header h1 {
    font-size: 2.5rem;
  }
  header p {
    font-size: 1.1rem;
  }
  nav a {
    font-size: 1rem;
  }
}