:root {
  --bg: #ffffff;
  --text: #1c2833;
  --muted: #56646f;
  --accent: #1f5f8b;
  --accent-dark: #143f5c;
  --surface: #f3f6f9;
  --border: #dbe3ea;
  --max: 1100px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12181e;
    --text: #e8eef3;
    --muted: #9fb0bd;
    --accent: #6db3e0;
    --accent-dark: #0d2a3f;
    --surface: #1b242c;
    --border: #2b3946;
  }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
}
a { color: var(--accent); }
.visually-hidden {
  position: absolute; width: 1px; height: 1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap;
}
.skip-link {
  position: absolute; left: -999px; top: 0; background: var(--accent); color: #fff;
  padding: .5rem 1rem; z-index: 100;
}
.skip-link:focus { left: 0; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: var(--bg); border-bottom: 1px solid var(--border);
}
.nav {
  max-width: var(--max); margin: 0 auto; padding: .75rem 1.25rem;
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: .5rem 1.5rem;
}
.brand { font-weight: 700; font-size: 1.15rem; text-decoration: none; color: var(--text); }
.nav-links { list-style: none; display: flex; gap: 1.25rem; margin: 0; padding: 0; }
.nav-links a { text-decoration: none; color: var(--muted); font-weight: 500; }
.nav-links a:hover, .nav-links a:focus { color: var(--accent); }

/* Hero */
.hero { position: relative; min-height: 420px; display: flex; align-items: center; color: #fff; overflow: hidden; }
.hero-img { position: absolute; inset: 0; background-size: cover; background-position: center; }
.hero-overlay { position: absolute; inset: 0; background: linear-gradient(90deg, rgba(10,30,45,.82), rgba(10,30,45,.35)); }
.hero-content { position: relative; max-width: var(--max); margin: 0 auto; padding: 3rem 1.25rem; width: 100%; }
.hero h1 { font-size: clamp(2rem, 5vw, 3.25rem); margin: 0 0 1rem; line-height: 1.15; }
.hero p { max-width: 640px; font-size: 1.15rem; margin: 0; }

/* Fallback backgrounds (shown if remote images cannot load) */
.fallback-1 { background-image: linear-gradient(135deg, #1f5f8b, #0f2f45); }
.fallback-2 { background-image: linear-gradient(135deg, #2e7d9a, #164a63); }
.fallback-3 { background-image: linear-gradient(135deg, #4a6fa5, #1d2f52); }
.fallback-4 { background-image: linear-gradient(135deg, #3a8a76, #16473c); }

/* Sections */
.section { max-width: var(--max); margin: 0 auto; padding: 3rem 1.25rem; }
.section.narrow { max-width: 820px; }
.section h2 { font-size: 1.6rem; margin: 0 0 1rem; }

/* Cards */
.cards { display: grid; gap: 1.5rem; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; overflow: hidden; }
.card-img { height: 190px; background-size: cover; background-position: center; }
.card-body { padding: 1.1rem 1.25rem 1.4rem; }
.card h3 { margin: 0 0 .4rem; font-size: 1.25rem; }
.card p { margin: 0; color: var(--muted); }

/* Projects */
.projects { padding-left: 1.2rem; }
.projects li { margin-bottom: .75rem; }

/* Form */
.form-wrap { border: 1px solid var(--border); border-radius: 12px; overflow: hidden; background: #fff; }
.form-wrap iframe { display: block; border: 0; }
.form-link { font-size: .95rem; }

/* Footer */
.site-footer { background: var(--accent-dark); color: #dbe7f0; padding: 2rem 1.25rem; text-align: center; }
.site-footer p { margin: 0 0 1rem; }
.site-footer address { font-style: normal; line-height: 1.7; }

@media (max-width: 560px) {
  .hero { min-height: 340px; }
  .nav-links { gap: .9rem; }
}