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

:root {
  --bg: #0f172a;
  --bg-surface: #1e293b;
  --bg-card: #1e293b;
  --bg-card-hover: #334155;
  --text: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent: #38bdf8;
  --accent-hover: #7dd3fc;
  --accent-dim: rgba(56, 189, 248, 0.12);
  --border: #334155;
  --radius: 12px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--accent);
  color: var(--bg);
  padding: 0.5rem 1rem;
  border-radius: 0 0 var(--radius) var(--radius);
  z-index: 100;
  font-weight: 600;
}
.skip-link:focus { top: 0; }

a { color: var(--accent); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent-hover); }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 2px; }

nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 0 1.5rem;
}
nav .nav-inner {
  max-width: 1100px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; min-height: 56px;
}
nav .logo { font-weight: 700; font-size: 1.05rem; color: var(--text); }
nav .logo a { color: inherit; }
nav .logo a:hover { color: var(--text); }
nav .logo span { color: var(--accent); }
nav .nav-right { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; justify-content: flex-end; }
nav ul { list-style: none; display: flex; gap: 1.25rem; }
nav ul a { color: var(--text-secondary); font-size: 0.9rem; font-weight: 500; }
nav ul a:hover { color: var(--accent); }
nav ul.nav-lang { gap: 0.35rem; }
nav ul.nav-lang a { font-size: 0.85rem; font-weight: 600; }
nav ul.nav-lang a[aria-current="page"] { color: var(--accent); }
nav ul.nav-lang .nav-sep { color: var(--text-muted); pointer-events: none; }

.container { max-width: 1100px; margin: 0 auto; padding: 0 1.5rem; }
section { padding: 3.5rem 0; }
.section-title { font-size: 1.5rem; font-weight: 700; margin-bottom: 0.5rem; }
.section-subtitle { color: var(--text-secondary); margin-bottom: 2rem; max-width: 42rem; }

.hero {
  min-height: calc(100vh - 56px);
  display: flex; align-items: center;
  position: relative; overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute; top: -40%; right: -15%; width: 560px; height: 560px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.1) 0%, transparent 70%);
  pointer-events: none;
}
.hero-content { position: relative; z-index: 1; max-width: 720px; }
.hero-label {
  display: inline-block;
  padding: 0.35rem 0.9rem;
  background: var(--accent-dim);
  border: 1px solid rgba(56, 189, 248, 0.25);
  border-radius: 999px;
  font-size: 0.85rem; font-weight: 500;
  color: var(--accent);
  margin-bottom: 1.25rem;
}
.hero h1 { font-size: clamp(2rem, 5vw, 2.75rem); font-weight: 800; line-height: 1.15; margin-bottom: 1rem; }
.hero h1 .accent { color: var(--accent); }
.hero .lead { font-size: 1.1rem; color: var(--text-secondary); margin-bottom: 1.75rem; max-width: 38rem; }
.hero-buttons { display: flex; gap: 1rem; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center;
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius);
  font-weight: 600; font-size: 0.95rem;
}
.btn-primary { background: var(--accent); color: var(--bg); }
.btn-primary:hover { background: var(--accent-hover); color: var(--bg); }
.btn-outline { border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { border-color: var(--accent); color: var(--accent); }

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
}
.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  transition: border-color 0.2s, background 0.2s;
}
.project-card:hover { background: var(--bg-card-hover); border-color: rgba(56, 189, 248, 0.35); }
.card-header { display: flex; align-items: flex-start; gap: 0.75rem; margin-bottom: 0.75rem; }
.card-icon { font-size: 1.5rem; line-height: 1; }
.project-card h3 { font-size: 1rem; font-weight: 600; }
.project-card h3 a { color: var(--text); }
.project-card h3 a:hover { color: var(--accent); }
.project-card .desc { font-size: 0.9rem; color: var(--text-secondary); margin-bottom: 0.75rem; }
.tags { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.tag {
  font-size: 0.75rem; font-weight: 500;
  padding: 0.2rem 0.55rem;
  border-radius: 999px;
  background: var(--accent-dim);
  color: var(--accent);
  border: 1px solid rgba(56, 189, 248, 0.2);
}

.link-list { list-style: none; display: grid; gap: 0.75rem; }
.link-list a { font-weight: 500; }
.link-list .meta { display: block; font-size: 0.85rem; color: var(--text-muted); font-weight: 400; margin-top: 0.15rem; }

footer {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
}
footer .links { display: flex; justify-content: center; gap: 1.5rem; flex-wrap: wrap; margin-bottom: 1rem; }