/* ====== Base ====== */
:root {
  --bg: #0f172a;          /* slate-900 */
  --panel: #111827;       /* gray-900 */
  --text: #e5e7eb;        /* gray-200 */
  --muted: #9ca3af;       /* gray-400 */
  --accent: #60a5fa;      /* blue-400 */
  --accent-2: #34d399;    /* emerald-400 */
  --card: #0b1220;        /* deeper */
  --border: #1f2937;      /* gray-800 */
  --shadow: rgba(0,0,0,0.4);
  --radius: 12px;
  --space: 18px;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  background: linear-gradient(180deg, var(--bg), #0b1220 60%, #0b1220);
  color: var(--text);
  line-height: 1.6;
}

/* ====== Layout ====== */
.container {
  width: min(1100px, 92%);
  margin: 0 auto;
}

.section {
  padding: 64px 0;
}

.section.alt {
  background: linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0.0));
}

/* ====== Header ====== */
.site-header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(10px);
  background: rgba(15, 23, 42, 0.7);
  border-bottom: 1px solid var(--border);
  z-index: 100;
}

.site-header .container {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: var(--space);
  padding: 14px 0;
}

.brand h1 {
  margin: 0;
  font-size: 1.6rem;
  letter-spacing: 0.4px;
}

.brand p {
  margin: 2px 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.nav {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.nav a {
  color: var(--text);
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 8px;
  transition: background 0.2s ease, color 0.2s ease;
}

.nav a:hover,
.nav a:focus {
  background: rgba(96,165,250,0.15);
  color: #fff;
  outline: none;
}

/* ====== Typography ====== */
h2 {
  font-size: 1.8rem;
  margin: 0 0 18px;
}

h3 {
  font-size: 1.2rem;
  margin: 0 0 10px;
}

p {
  margin: 0 0 12px;
}

.muted {
  color: var(--muted);
}

/* ====== Cards & Grid ====== */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: 0 6px 20px var(--shadow);
}

.grid {
  display: grid;
  gap: 18px;
}

.grid.two {
  grid-template-columns: repeat(2, 1fr);
}

@media (max-width: 820px) {
  .grid.two { grid-template-columns: 1fr; }
}

/* Projects grid auto-fit */
#projects .grid {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

/* ====== Lists & Tags ====== */
.list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 10px;
}

.list.columns {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 8px;
}

.tag {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 0.85rem;
  background: rgba(96,165,250,0.16);
  color: #cfe5ff;
  border: 1px solid rgba(96,165,250,0.35);
}

/* ====== Buttons ====== */
.btn {
  display: inline-block;
  margin-top: 10px;
  padding: 10px 14px;
  border-radius: 10px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  color: #081019;
  text-decoration: none;
  font-weight: 600;
  box-shadow: 0 6px 16px rgba(52, 211, 153, 0.25);
  transition: transform 0.15s ease, box-shadow 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(52, 211, 153, 0.35);
}

/* ====== Footer ====== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 22px 0 40px;
  text-align: center;
  color: var(--muted);
}

/* ====== Accessibility ====== */
a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}