/* Color system */
:root {
  --bg: #0b1220;
  --bg-elev: #0f172a;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --card: #111827;
  --border: #1f2937;
  --ring: rgba(56, 189, 248, 0.35);
}

[data-theme="light"] {
  --bg: #ffffff;
  --bg-elev: #f8fafc;
  --text: #0f172a;
  --muted: #475569;
  --accent: #0ea5e9;
  --card: #ffffff;
  --border: #e5e7eb;
  --ring: rgba(14, 165, 233, 0.25);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme]) {
    --bg: #ffffff;
    --bg-elev: #f8fafc;
    --text: #0f172a;
    --muted: #475569;
    --accent: #0ea5e9;
    --card: #ffffff;
    --border: #e5e7eb;
    --ring: rgba(14, 165, 233, 0.25);
  }
}

/* Base */
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, Arial, "Apple Color Emoji", "Segoe UI Emoji";
}

.container { max-width: 1024px; margin: 0 auto; padding: 0 16px; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 16px; background: var(--bg-elev); padding: 8px 12px; border-radius: 8px; }

/* Header */
.site-header { position: sticky; top: 0; backdrop-filter: blur(10px); background: color-mix(in oklab, var(--bg) 80%, transparent); border-bottom: 1px solid var(--border); z-index: 10; }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand a { color: var(--text); font-weight: 700; letter-spacing: 0.2px; }
.nav a { margin: 0 10px; color: var(--muted); }
.nav a:hover { color: var(--text); text-decoration: none; }
.theme-toggle { background: transparent; color: var(--muted); border: 1px solid var(--border); border-radius: 10px; padding: 6px 10px; cursor: pointer; }
.theme-toggle:focus { outline: 2px solid var(--ring); outline-offset: 2px; }

/* Hero */
.hero { padding: 64px 0 24px; background: radial-gradient(800px 400px at 10% -10%, color-mix(in oklab, var(--accent) 20%, transparent), transparent), radial-gradient(800px 400px at 90% -10%, color-mix(in oklab, var(--accent) 15%, transparent), transparent); }
.hero h1 { font-size: clamp(28px, 4vw, 42px); margin: 0 0 8px; }
.hero .lead { font-weight: 600; margin: 0 0 8px; color: var(--text); }
.hero .muted { color: var(--muted); max-width: 70ch; }
.accent { color: var(--accent); }
.actions { display: flex; gap: 12px; margin-top: 16px; flex-wrap: wrap; }
.btn { display: inline-block; padding: 10px 14px; border: 1px solid var(--border); border-radius: 10px; color: var(--text); background: var(--bg-elev); text-decoration: none; }
.btn.primary { background: var(--accent); color: #041017; border-color: color-mix(in oklab, var(--accent) 80%, black); }
.social { margin-top: 10px; display: flex; gap: 16px; }

/* Sections */
.section { padding: 40px 0; border-top: 1px solid var(--border); background: var(--bg); }
.section h2 { margin: 0 0 16px; font-size: 22px; }

/* Experience */
.timeline { list-style: none; padding: 0; margin: 0; display: grid; gap: 18px; }
.role { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; }
.role .meta { color: var(--muted); font-size: 14px; }
.bullets { margin: 8px 0 0 0; color: var(--muted); }

/* Projects */
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 16px; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 16px; }
.card h3 { margin: 0 0 8px; }
.tags { color: var(--muted); font-size: 14px; margin: 4px 0 8px; }
.links a { margin-right: 12px; }

/* Project group headings */
.project-group { margin: 20px 0; }
.subsection-title { margin: 8px 0 12px; color: var(--text); font-weight: 700; display: flex; align-items: center; gap: 12px; }
.subsection-title::after { content: ""; height: 1px; background: #ffffff; opacity: 0.25; flex: 1; }

/* Footer */
.site-footer { border-top: 1px solid var(--border); padding: 20px 0; color: var(--muted); }
.site-footer .container { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.sep { opacity: 0.5; }

/* Responsive tweaks */
@media (max-width: 640px) {
  .role { flex-direction: column; align-items: flex-start; }
}