/*
  Lightweight, accessible, responsive styles with system color-scheme support
*/

:root {
  --bg: #ffffff;
  --text: #0b1220;
  --muted: #5b6475;
  --surface: #f4f6fb;
  --card: #ffffff;
  --border: #e4e8f0;
  --link: #0b6cff;
  --link-visited: #6b4eff;
  --accent: #0b6cff;
}

[data-theme="dark"] {
  --bg: #0d1117;
  --text: #e6edf3;
  --muted: #9aa7b5;
  --surface: #0f141b;
  --card: #111827;
  --border: #232b36;
  --link: #619bff;
  --link-visited: #b18cff;
  --accent: #7aa2ff;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  line-height: 1.6;
  background: var(--bg);
  color: var(--text);
  overflow-x: hidden;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 16px;
}

.site-header {
  position: sticky;
  top: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}

.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
}

.brand__title {
  font-size: clamp(1.1rem, 2vw + 0.6rem, 1.5rem);
  margin: 0;
}

.brand__tag {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.nav__list {
  list-style: none;
  display: flex;
  gap: 12px;
  padding: 0;
  margin: 0 12px 0 0;
}

/* Ensure nav links and theme toggle sit on one row */
.nav {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: nowrap;
}

.nav__list a { color: var(--text); text-decoration: none; }
.nav__list a:hover, .nav__list a:focus { text-decoration: underline; }

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 10px;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 10px;
  border: 1px solid transparent;
  background: transparent;
  font-size: 20px;
  line-height: 1;
}
.icon-btn:hover, .icon-btn:focus {
  background: var(--surface);
  border-color: var(--border);
}
.icon-btn--primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.skip-link {
  position: absolute;
  left: -9999px;
}
.skip-link:focus {
  left: 8px;
  top: 8px;
  background: var(--accent);
  color: #fff;
  padding: 8px 12px;
  border-radius: 6px;
}

.section { padding: 32px 0; }
.section { scroll-margin-top: 72px; }
.hero { padding-top: 40px; }

.hero__kicker {
  color: var(--muted);
  margin: 0 0 6px 0;
}
.hero__lead {
  font-size: clamp(1rem, 1.2vw + 0.9rem, 1.2rem);
  margin: 0 0 16px 0;
}

.actions { display: flex; flex-wrap: wrap; gap: 12px; }

.hero__media { margin-top: 16px; }
.hero__photo {
  width: 100%;
  max-width: 520px;
  height: auto;
  display: block;
  border-radius: 12px;
  border: 1px solid var(--border);
}

/* Two-column hero on wider screens */
@media (min-width: 900px) {
  .hero {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    align-items: center;
    gap: 24px;
  }
  .hero__media { margin-top: 0; justify-self: end; }
}

.btn {
  display: inline-block;
  padding: 10px 14px;
  border-radius: 10px;
  border: 1px solid var(--accent);
  background: var(--accent);
  color: #fff;
  text-decoration: none;
}
.btn--secondary {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
  background: var(--surface);
}
.btn--outline {
  background: transparent;
  color: var(--accent);
  border-color: var(--accent);
}
.btn--small { padding: 6px 10px; border-radius: 8px; }

.grid { display: grid; gap: 16px; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

.stack { display: grid; gap: 12px; }
.project { border: 1px solid var(--border); border-radius: 12px; background: var(--card); }
.project__body { padding: 14px 16px; }
.project__title { margin: 0 0 4px 0; }

.checklist { padding-left: 20px; }

.contact-list { list-style: none; padding: 0; margin: 0; }
.contact-list li { margin: 6px 0; }

.inline-link { color: var(--link); }
.inline-link:visited { color: var(--link-visited); }
.inline-link:hover, .inline-link:focus { text-decoration: underline; }

.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 24px;
}
.footer-row {
  display: flex; align-items: center; justify-content: space-between; padding: 16px 0;
}

.visually-hidden {
  position: absolute !important;
  clip: rect(1px, 1px, 1px, 1px);
  padding: 0 !important;
  border: 0 !important;
  height: 1px !important;
  width: 1px !important;
  overflow: hidden;
  white-space: nowrap;
}

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

/* Mobile optimizations */
@media (max-width: 520px) {
  .container { padding: 0 12px; }
  .header-row { flex-direction: column; align-items: flex-start; gap: 8px; }
  .nav { width: 100%; justify-content: space-between; }
  .nav__list { gap: 6px; }
  .brand__tag { display: none; }
  .btn { padding: 9px 12px; }
  .icon-btn { width: 40px; height: 40px; font-size: 18px; }
  .theme-toggle { width: 40px; height: 40px; }
  .section { padding: 24px 0; }
}