/* ===== Design tokens ===== */
:root {
  --bg: #ffffff;
  --bg-alt: #f5f7fa;
  --surface: #ffffff;
  --text: #1a2332;
  --text-muted: #5a6b7f;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.1);
  --border: #e2e8f0;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 10px 32px rgba(0, 0, 0, 0.12);
  --radius: 12px;
  --maxw: 1080px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: "SF Mono", "Fira Code", "Roboto Mono", ui-monospace, monospace;
}

:root[data-theme="dark"] {
  --bg: #0a192f;
  --bg-alt: #112240;
  --surface: #112240;
  --text: #e6f1ff;
  --text-muted: #8892b0;
  --accent: #64ffda;
  --accent-soft: rgba(100, 255, 218, 0.1);
  --border: #233554;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  --shadow-hover: 0 10px 32px rgba(2, 12, 27, 0.7);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0a192f;
    --bg-alt: #112240;
    --surface: #112240;
    --text: #e6f1ff;
    --text-muted: #8892b0;
    --accent: #64ffda;
    --accent-soft: rgba(100, 255, 218, 0.1);
    --border: #233554;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 10px 32px rgba(2, 12, 27, 0.7);
  }
}

/* ===== Base ===== */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background 0.3s ease, color 0.3s ease;
}
a { color: var(--accent); text-decoration: none; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand {
  font-family: var(--mono); font-weight: 700; font-size: 1.25rem;
  color: var(--accent); border: 2px solid var(--accent);
  width: 40px; height: 40px; display: grid; place-items: center; border-radius: 8px;
}
.nav-links { display: flex; align-items: center; gap: 28px; list-style: none; }
.nav-links a { color: var(--text); font-size: 0.9rem; transition: color 0.2s; }
.nav-links a:hover { color: var(--accent); }
.theme-toggle, .nav-toggle {
  background: none; border: none; cursor: pointer; font-size: 1.1rem; color: var(--text);
}
.nav-toggle { display: none; flex-direction: column; gap: 5px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--text); border-radius: 2px; transition: 0.3s; }

/* ===== Hero ===== */
.hero { min-height: calc(100vh - 64px); display: flex; align-items: center; }
.eyebrow { font-family: var(--mono); color: var(--accent); font-size: 0.95rem; margin-bottom: 16px; }
.hero h1 { font-size: clamp(2.5rem, 8vw, 4.5rem); line-height: 1.1; letter-spacing: -1px; }
.hero-subtitle { font-size: clamp(1.5rem, 5vw, 3rem); color: var(--text-muted); line-height: 1.1; margin-top: 4px; }
.hero-bio { max-width: 560px; color: var(--text-muted); margin-top: 24px; font-size: 1.05rem; }
.hero-cta { display: flex; gap: 16px; margin-top: 40px; flex-wrap: wrap; }
.hero-stats { list-style: none; display: flex; gap: 40px; margin-top: 40px; flex-wrap: wrap; }
.hero-stats li { display: flex; flex-direction: column; }
.hero-stats strong { font-size: 1.6rem; color: var(--accent); line-height: 1.1; }
.hero-stats span { font-family: var(--mono); font-size: 0.8rem; color: var(--text-muted); }

/* ===== Buttons ===== */
.btn {
  display: inline-block; padding: 14px 28px; border-radius: 8px;
  font-size: 0.95rem; font-weight: 500; cursor: pointer; transition: all 0.2s;
  border: 1px solid var(--accent);
}
.btn-primary { background: var(--accent); color: var(--bg); }
.btn-primary:hover { transform: translateY(-3px); box-shadow: var(--shadow-hover); }
.btn-ghost { background: transparent; color: var(--accent); }
.btn-ghost:hover { background: var(--accent-soft); transform: translateY(-3px); }

/* ===== Sections ===== */
.section { padding: 100px 24px; }
.section-title {
  display: flex; align-items: center; gap: 12px;
  font-size: clamp(1.5rem, 4vw, 2rem); margin-bottom: 48px; white-space: nowrap;
}
.section-title::after {
  content: ""; height: 1px; background: var(--border); width: 100%; max-width: 300px;
}
.section-num { font-family: var(--mono); color: var(--accent); font-size: 1.1rem; font-weight: 400; }

/* ===== About ===== */
.about-grid { display: grid; grid-template-columns: 3fr 2fr; gap: 48px; align-items: start; }
.about-text p { color: var(--text-muted); margin-bottom: 16px; }
.skills { list-style: none; display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px 24px; margin-top: 12px; }
.skills li { font-family: var(--mono); font-size: 0.85rem; color: var(--text-muted); position: relative; padding-left: 20px; }
.skills li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); }
.about-photo { display: grid; place-items: center; }
.photo-placeholder {
  width: 240px; height: 240px; border-radius: var(--radius);
  border: 2px solid var(--accent); display: grid; place-items: center;
  color: var(--text-muted); background: var(--accent-soft);
}

/* ===== Cards ===== */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 24px; }
.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow); transition: transform 0.2s, box-shadow 0.2s;
  display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); }
.card-featured { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent), var(--shadow); }
.section-footnote { margin-top: 32px; color: var(--text-muted); font-size: 0.95rem; }
.section-footnote code { font-family: var(--mono); font-size: 0.85em; background: var(--accent-soft); color: var(--accent); padding: 2px 6px; border-radius: 5px; }

/* ===== Subsection heading (Apps groups) ===== */
.subsection-title { font-family: var(--mono); font-size: 1rem; color: var(--accent); margin-bottom: 24px; }
.subsection-title + .cards { margin-bottom: 8px; }
.cards + .subsection-title { margin-top: 56px; }

/* ===== Company label + delisted note on app cards ===== */
.card-company { font-family: var(--mono); font-size: 0.75rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 4px; }
.card-note { font-family: var(--mono); font-size: 0.8rem; color: var(--text-muted); font-style: italic; }

/* ===== Experience extra lines ===== */
.exp-tech { font-family: var(--mono); font-size: 0.8rem; color: var(--text-muted); margin-top: 12px; }
.exp-ship { font-size: 0.85rem; color: var(--text-muted); margin-top: 12px; }
.about-edu { font-size: 0.95rem; }
.card-icon { font-size: 2rem; margin-bottom: 16px; }
.card h3 { font-size: 1.2rem; margin-bottom: 10px; }
.card p { color: var(--text-muted); font-size: 0.95rem; flex-grow: 1; }
.card-tags { display: flex; flex-wrap: wrap; gap: 8px; margin: 16px 0; }
.card-tags span { font-family: var(--mono); font-size: 0.75rem; color: var(--accent); background: var(--accent-soft); padding: 4px 10px; border-radius: 999px; }
.card-link { font-family: var(--mono); font-size: 0.85rem; font-weight: 500; }
.card-link:hover { text-decoration: underline; }

/* ===== Timeline ===== */
.timeline { display: flex; flex-direction: column; gap: 32px; }
.timeline-item { display: grid; grid-template-columns: 160px 1fr; gap: 24px; }
.timeline-date { font-family: var(--mono); font-size: 0.85rem; color: var(--text-muted); }
.timeline-content h3 { font-size: 1.15rem; margin-bottom: 12px; }
.timeline-content .at { color: var(--accent); font-weight: 400; }
.timeline-content ul { list-style: none; display: flex; flex-direction: column; gap: 8px; }
.timeline-content li { color: var(--text-muted); position: relative; padding-left: 22px; font-size: 0.95rem; }
.timeline-content li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); }

/* ===== Contact ===== */
.section-contact { text-align: center; max-width: 640px; }
.contact-title { font-size: clamp(2rem, 6vw, 3rem); margin: 12px 0 20px; }
.contact-text { color: var(--text-muted); margin-bottom: 40px; }
.contact-cta { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ===== Footer ===== */
.site-footer { text-align: center; padding: 48px 24px; border-top: 1px solid var(--border); }
.social { list-style: none; display: flex; justify-content: center; gap: 28px; margin-bottom: 20px; }
.social a { font-family: var(--mono); font-size: 0.9rem; color: var(--text-muted); }
.social a:hover { color: var(--accent); }
.footer-note { font-family: var(--mono); font-size: 0.8rem; color: var(--text-muted); }

/* ===== Responsive ===== */
@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed; top: 64px; right: 0; height: calc(100vh - 64px); width: 70%;
    flex-direction: column; align-items: flex-start; gap: 24px; padding: 40px 32px;
    background: var(--bg-alt); border-left: 1px solid var(--border);
    transform: translateX(100%); transition: transform 0.3s ease;
  }
  .nav-links.open { transform: translateX(0); }
  .about-grid { grid-template-columns: 1fr; }
  .about-photo { order: -1; }
  .timeline-item { grid-template-columns: 1fr; gap: 8px; }
  .section { padding: 72px 24px; }
}