/* ============================================================
   Klemens Hauzenberger — personal academic homepage
   Hand-written design system. No build step, no framework.
   ============================================================ */

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

/* ---------- Design tokens ---------- */
:root {
  --primary:        #0e4f52;
  --primary-light:  #14747a;
  --accent:         #b45c2e;
  --accent-soft:    rgba(180, 92, 46, .12);

  --bg:             #fbfaf8;
  --bg-tint:        #f4f1ec;
  --surface:        #ffffff;
  --text:           #17252b;
  --text-muted:     #5b6b73;
  --border:         #e4dfd7;

  --shadow:    0 1px 2px rgba(23,37,43,.06), 0 2px 6px rgba(23,37,43,.05);
  --shadow-lg: 0 4px 12px rgba(23,37,43,.10), 0 12px 28px rgba(23,37,43,.07);

  --radius:    10px;
  --radius-sm: 6px;
  --max-w:     1080px;
  --measure:   68ch;

  --font-body: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-head: 'Source Serif 4', Georgia, 'Times New Roman', serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
}

/* ---------- Base ---------- */
html { font-size: 16px; scroll-behavior: smooth; color-scheme: light; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 { font-family: var(--font-head); line-height: 1.25; font-weight: 600; }
h1 { font-size: clamp(2rem, 1.4rem + 2.4vw, 3rem); letter-spacing: -.015em; }
h2 { font-size: clamp(1.4rem, 1.15rem + 1vw, 1.8rem); letter-spacing: -.01em; }
h3 { font-size: 1.125rem; }

p { max-width: var(--measure); }

a { color: var(--primary-light); text-decoration: none; transition: color .18s ease; }
a:hover { color: var(--accent); }
a.underlined { text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; }

:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

img { max-width: 100%; display: block; }
[hidden] { display: none !important; }
code, kbd { font-family: var(--font-mono); font-size: .875em; }

.skip-link {
  position: absolute; left: 1rem; top: -4rem; z-index: 100;
  background: var(--surface); color: var(--text);
  padding: .6rem 1rem; border-radius: var(--radius-sm);
  border: 1px solid var(--border); box-shadow: var(--shadow-lg);
  transition: top .2s ease;
}
.skip-link:focus { top: 1rem; }

/* ---------- Layout helpers ---------- */
.wrap { width: 100%; max-width: var(--max-w); margin-inline: auto; padding-inline: 1.5rem; }
.stack > * + * { margin-top: 1rem; }
.stack-sm > * + * { margin-top: .5rem; }
.muted { color: var(--text-muted); }
.small { font-size: .9rem; }
.center { text-align: center; }

/* ---------- Navbar ---------- */
.navbar {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.navbar-inner {
  max-width: var(--max-w); margin-inline: auto;
  padding: .75rem 1.5rem;
  display: flex; align-items: center; gap: 1rem;
}
.nav-brand {
  font-family: var(--font-head); font-weight: 600; font-size: 1.05rem;
  color: var(--text); margin-right: auto; letter-spacing: -.01em;
}
.nav-brand:hover { color: var(--primary-light); }

.nav-links { list-style: none; display: flex; align-items: center; gap: .25rem; }
.nav-links a {
  display: block; padding: .4rem .7rem; border-radius: var(--radius-sm);
  color: var(--text-muted); font-size: .925rem; font-weight: 500;
  transition: background .18s ease, color .18s ease;
}
.nav-links a:hover { background: var(--bg-tint); color: var(--text); }
.nav-links a.active { color: var(--primary); background: var(--accent-soft); }

.nav-toggle {
  background: none; border: 1px solid var(--border); color: var(--text);
  border-radius: var(--radius-sm); cursor: pointer;
  width: 2.25rem; height: 2.25rem;
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 1rem; transition: background .18s ease;
}
.nav-toggle:hover { background: var(--bg-tint); }
.nav-toggle { display: none; }

/* ---------- Hero ---------- */
.hero { border-bottom: 1px solid var(--border); background: var(--bg-tint); }
.hero-inner {
  max-width: var(--max-w); margin-inline: auto;
  padding: 3.5rem 1.5rem;
  display: grid; grid-template-columns: 240px 1fr; gap: 2.75rem; align-items: center;
}
.hero-photo {
  width: 240px; height: 300px; object-fit: cover; object-position: center top;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
}
.eyebrow {
  font-size: .8rem; font-weight: 600; letter-spacing: .09em;
  text-transform: uppercase; color: var(--accent); margin-bottom: .5rem;
}
.hero h1 { margin-bottom: .5rem; }
.subtitle { color: var(--text-muted); font-size: 1.05rem; }
.hero-lede { margin-top: 1rem; font-size: 1.05rem; }

.hero-email {
  margin-top: .55rem;
  font-family: var(--font-mono);
  font-size: .95rem;
}

.hero-actions { margin-top: 1.5rem; display: flex; flex-wrap: wrap; gap: .75rem; }
.button {
  display: inline-block; padding: .6rem 1.15rem;
  border-radius: var(--radius-sm); font-size: .925rem; font-weight: 500;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .15s ease, box-shadow .18s ease, background .18s ease;
}
.button:hover { transform: translateY(-1px); }
.button-primary { background: var(--primary); color: #fff; box-shadow: var(--shadow); }
.button-primary:hover { background: var(--primary-light); color: #fff; }
.button-secondary { background: var(--surface); color: var(--text); border-color: var(--border); }
.button-secondary:hover { border-color: var(--primary-light); color: var(--primary-light); }

/* ---------- Page header (subpages) ---------- */
.page-header { border-bottom: 1px solid var(--border); background: var(--bg-tint); }
.page-header-inner { max-width: var(--max-w); margin-inline: auto; padding: 2.5rem 1.5rem; }
.page-header p { margin-top: .5rem; color: var(--text-muted); }

.main-flush { padding-block: 0; }

/* ---------- Sections & cards ---------- */
main { padding-block: 3rem; }
.section + .section { margin-top: 3rem; }
.section > h2 { margin-bottom: 1.25rem; }

.card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.5rem; box-shadow: var(--shadow);
}
.card + .card { margin-top: 1.25rem; }
.card > h2, .card > h3 { margin-bottom: .75rem; }

.grid { display: grid; gap: 1.25rem; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }

.info-grid { display: grid; grid-template-columns: max-content 1fr; gap: .5rem 1.5rem; }
.info-grid dt { font-weight: 600; color: var(--text-muted); font-size: .925rem; }
.info-grid dd { margin: 0; }

/* Research-area / feature tiles */
.tile { border-left: 3px solid var(--accent); padding-left: 1rem; }
.tile h3 { margin-bottom: .35rem; }
.tile p { color: var(--text-muted); font-size: .95rem; }

/* Timeline entries (CV, teaching) */
.entry { display: grid; grid-template-columns: 8.5rem 1fr; gap: 1.25rem; }
.entry + .entry { margin-top: 1.25rem; padding-top: 1.25rem; border-top: 1px solid var(--border); }
.entry-when { font-family: var(--font-mono); font-size: .85rem; color: var(--text-muted); padding-top: .2rem; }
.entry-what h3 { margin-bottom: .15rem; }
.entry-where { color: var(--text-muted); font-size: .95rem; }

/* Tags */
.tags { display: flex; flex-wrap: wrap; gap: .4rem; margin-top: .6rem; }
.tag {
  font-size: .78rem; font-weight: 500; font-family: var(--font-mono);
  padding: .15rem .55rem; border-radius: 999px;
  background: var(--bg-tint); color: var(--text-muted); border: 1px solid var(--border);
}

/* ---------- Teaching ---------- */
.course-item { padding: 1rem 0; }
.course-item:first-of-type { padding-top: .25rem; }
.course-item + .course-item { border-top: 1px solid var(--border); }
.course-title {
  font-family: var(--font-head); font-size: 1.05rem; font-weight: 600;
  margin-bottom: .15rem;
}
.course-meta { font-size: .95rem; color: var(--text-muted); }

/* ---------- Publications ---------- */
.pub-item { padding: 1rem 0; }
.pub-item + .pub-item { border-top: 1px solid var(--border); }
.pub-title { font-family: var(--font-head); font-size: 1.05rem; font-weight: 600; }
.pub-authors { font-size: .95rem; color: var(--text-muted); }
.pub-venue { font-size: .95rem; }
.pub-venue em { color: var(--text-muted); }
.pub-links { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: .4rem; font-size: .875rem; }
.pub-links a::after { content: " \2197"; font-size: .8em; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border); background: var(--bg-tint);
  margin-top: 4rem; padding-block: 2rem;
}
.footer-inner {
  max-width: var(--max-w); margin-inline: auto; padding-inline: 1.5rem;
  display: flex; flex-wrap: wrap; gap: 1rem; justify-content: space-between; align-items: center;
}
.footer-links { display: flex; flex-wrap: wrap; gap: 1rem; list-style: none; font-size: .925rem; }

/* ---------- Wide content must scroll, never the page ---------- */
.scroll-x { overflow-x: auto; }

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .hero-inner { grid-template-columns: 1fr; text-align: center; padding-block: 2.5rem; }
  .hero-photo { margin-inline: auto; width: 200px; height: 250px; }
  .hero p, .hero-lede { margin-inline: auto; }
  .hero-actions { justify-content: center; }
}

@media (max-width: 768px) {
  .nav-toggle { display: inline-flex; order: 3; }
  .nav-links {
    display: none; order: 4; flex-basis: 100%; flex-direction: column;
    align-items: stretch; gap: .15rem; padding-top: .5rem;
  }
  .nav-links.open { display: flex; }
  .entry { grid-template-columns: 1fr; gap: .25rem; }
  .info-grid { grid-template-columns: 1fr; gap: .15rem 0; }
  .info-grid dd + dt { margin-top: .75rem; }
}