/* Ahmed H. Zahran — personal site. Plain CSS, no framework. */
:root {
  --bg: #ffffff;
  --bg-alt: #f3f6fa;
  --card: #ffffff;
  --text: #1c2733;
  --muted: #55636f;
  --border: #d7dee6;
  --accent: #0b5cad;
  --accent-strong: #084685;
  --accent-soft: #e3effb;
  --award: #8a5a00;
  --award-bg: #fff3d6;
  --shadow: 0 1px 2px rgba(16, 32, 48, .06), 0 4px 14px rgba(16, 32, 48, .06);
  --radius: 10px;
  --maxw: 1080px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1720;
    --bg-alt: #141e29;
    --card: #182432;
    --text: #e6edf3;
    --muted: #a3b1bf;
    --border: #2b3a4a;
    --accent: #7ab8ff;
    --accent-strong: #a8d0ff;
    --accent-soft: #1b2f47;
    --award: #f3c76b;
    --award-bg: #3a2f14;
    --shadow: none;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 4.5rem; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { transition: none !important; } }
body {
  margin: 0;
  font: 1rem/1.65 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  -webkit-text-size-adjust: 100%;
}
img { max-width: 100%; height: auto; }
a { color: var(--accent); text-underline-offset: 2px; }
a:hover { color: var(--accent-strong); }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; border-radius: 3px; }
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 .6rem; }
h2 { font-size: 1.75rem; }
h3 { font-size: 1.2rem; }
h4 { font-size: 1.02rem; }
p { margin: 0 0 1rem; }
ul, ol { padding-left: 1.4rem; margin: 0 0 1rem; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 1rem; }
.muted { color: var(--muted); }
.small { font-size: .9rem; }

.skip-link {
  position: absolute; left: .5rem; top: -4rem; z-index: 100;
  background: var(--accent); color: #fff; padding: .6rem 1rem; border-radius: 6px;
}
.skip-link:focus { top: .5rem; color: #fff; }

/* Header / nav */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: var(--bg); border-bottom: 1px solid var(--border);
}
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 3.5rem; }
.brand { font-weight: 700; font-size: 1.1rem; color: var(--text); text-decoration: none; }
.brand:hover { color: var(--accent); }
.nav-toggle {
  display: none; background: none; border: 1px solid var(--border); color: var(--text);
  border-radius: 6px; padding: .4rem .7rem; font: inherit; cursor: pointer;
}
.site-nav ul { display: flex; flex-wrap: wrap; gap: .15rem .25rem; list-style: none; margin: 0; padding: 0; }
.site-nav a {
  display: block; padding: .4rem .65rem; border-radius: 6px; color: var(--text);
  text-decoration: none; font-size: .95rem;
}
.site-nav a:hover { background: var(--accent-soft); color: var(--accent-strong); }
.site-nav a[aria-current] { background: var(--accent-soft); color: var(--accent-strong); font-weight: 600; }
@media (max-width: 860px) {
  .nav-toggle { display: inline-block; }
  .site-header .wrap { flex-wrap: wrap; padding-top: .4rem; padding-bottom: .4rem; }
  .site-nav { width: 100%; display: none; }
  .site-nav.open { display: block; }
  .site-nav ul { flex-direction: column; padding-bottom: .5rem; }
  .site-nav a { padding: .65rem .5rem; }
}

/* Hero */
.hero { padding: 2.5rem 0 2rem; background: linear-gradient(180deg, var(--accent-soft), var(--bg)); }
.hero .wrap { display: grid; grid-template-columns: 230px 1fr; gap: 2rem; align-items: center; }
.portrait { width: 230px; height: 230px; border-radius: 50%; object-fit: cover; object-position: center 20%; border: 4px solid var(--card); box-shadow: var(--shadow); }
.hero h1 { font-size: 2.3rem; margin-bottom: .2rem; }
.hero .role { font-size: 1.15rem; color: var(--muted); margin-bottom: 1rem; }
.hero p.lead { max-width: 46rem; }
.btn-row { display: flex; flex-wrap: wrap; gap: .6rem; margin: 1rem 0 .6rem; }
.btn {
  display: inline-block; padding: .55rem 1.1rem; border-radius: 999px; text-decoration: none;
  border: 1px solid var(--accent); font-weight: 600; font-size: .95rem;
}
.btn.primary { background: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-strong); color: #fff; }
.btn.ghost { color: var(--accent); background: transparent; }
.btn.ghost:hover { background: var(--accent-soft); }
.profile-links { display: flex; gap: 1rem; flex-wrap: wrap; font-size: .95rem; }
@media (max-width: 700px) {
  .hero .wrap { grid-template-columns: 1fr; text-align: center; justify-items: center; }
  .btn-row, .profile-links { justify-content: center; }
  .hero h1 { font-size: 1.9rem; }
  .portrait { width: 180px; height: 180px; }
}

/* Sections */
section.block { padding: 3rem 0; }
section.block.alt { background: var(--bg-alt); }
.section-kicker { text-transform: uppercase; letter-spacing: .08em; font-size: .78rem; color: var(--accent); font-weight: 700; margin-bottom: .2rem; }
.section-intro { color: var(--muted); max-width: 46rem; }

.grid { display: grid; gap: 1.1rem; }
.grid.two { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid.three { grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); }
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 1.2rem 1.3rem; box-shadow: var(--shadow);
}
.card h3 { margin-bottom: .35rem; }
.card ul { margin-bottom: 0; padding-left: 1.1rem; }
.card li { margin-bottom: .45rem; }
.card .meta { font-size: .85rem; color: var(--muted); margin-bottom: .4rem; }
.tag { display: inline-block; font-size: .72rem; font-weight: 700; padding: .1rem .5rem; border-radius: 999px; background: var(--accent-soft); color: var(--accent-strong); margin-left: .35rem; vertical-align: middle; }
.tag.award { background: var(--award-bg); color: var(--award); }

/* Timeline */
.timeline { list-style: none; padding: 0; margin: 0; border-left: 2px solid var(--border); }
.timeline > li { position: relative; padding: 0 0 1.3rem 1.3rem; margin: 0; }
.timeline > li::before {
  content: ""; position: absolute; left: -7px; top: .45rem; width: 12px; height: 12px;
  border-radius: 50%; background: var(--accent); border: 2px solid var(--bg);
}
.alt .timeline > li::before { border-color: var(--bg-alt); }
.timeline .when { font-size: .85rem; color: var(--muted); }
.timeline h3 { font-size: 1.08rem; margin-bottom: .1rem; }
.timeline .where { color: var(--muted); margin-bottom: .3rem; }
.timeline ul { margin: .3rem 0 0; }
.timeline .sub { margin-top: .5rem; }

/* Tables */
.table-wrap { overflow-x: auto; }
table { border-collapse: collapse; width: 100%; font-size: .95rem; }
caption { text-align: left; font-weight: 700; padding-bottom: .4rem; }
th, td { text-align: left; vertical-align: top; padding: .55rem .7rem; border-bottom: 1px solid var(--border); }
thead th { background: var(--accent-soft); color: var(--accent-strong); border-bottom: 2px solid var(--accent); }
tbody tr:hover { background: var(--accent-soft); }
td.nowrap, th.nowrap { white-space: nowrap; }
@media (max-width: 700px) {
  table.stack thead { position: absolute; left: -9999px; }
  table.stack tr { display: block; border-bottom: 1px solid var(--border); padding: .5rem 0; }
  table.stack td { display: block; border: 0; padding: .15rem .2rem; white-space: normal; }
  table.stack td::before { content: attr(data-label) ": "; font-weight: 700; color: var(--muted); }
  table.stack td:first-child::before { content: ""; }
  table.stack td:first-child { font-weight: 600; }
}

/* Details */
details { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); margin: 0 0 .8rem; }
details > summary { cursor: pointer; padding: .8rem 1.1rem; font-weight: 600; list-style: none; }
details > summary::-webkit-details-marker { display: none; }
details > summary::before { content: "▸"; display: inline-block; width: 1.1rem; color: var(--accent); transition: transform .15s; }
details[open] > summary::before { transform: rotate(90deg); }
details > .details-body { padding: 0 1.1rem 1rem; }

.logos { display: flex; flex-wrap: wrap; gap: .8rem 1.2rem; align-items: center; margin-top: 1rem; }
.logos img { height: 46px; width: auto; background: #fff; padding: 4px 8px; border-radius: 6px; border: 1px solid var(--border); }

.cols { columns: 2 320px; column-gap: 2rem; }
.cols li { break-inside: avoid; }

.award-list { list-style: none; padding: 0; margin: 0; }
.award-list li { display: grid; grid-template-columns: 8.5rem 1fr; gap: .8rem; padding: .5rem 0; border-bottom: 1px solid var(--border); }
.award-list .when { font-weight: 600; color: var(--muted); }
@media (max-width: 560px) { .award-list li { grid-template-columns: 1fr; gap: 0; } }

.news-photo { width: 100%; max-height: 260px; object-fit: cover; object-position: center 25%; border-radius: 8px; margin-bottom: .8rem; }

/* Publications page */
.page-head { padding: 2rem 0 1rem; background: linear-gradient(180deg, var(--accent-soft), var(--bg)); }
.filters {
  display: grid; gap: .8rem 1rem; grid-template-columns: 2fr 1fr 1fr auto; align-items: end;
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem; margin: 1rem 0;
}
.filters label { display: block; font-size: .82rem; font-weight: 600; color: var(--muted); margin-bottom: .2rem; }
.filters input[type=search], .filters select {
  width: 100%; padding: .5rem .6rem; font: inherit; color: var(--text); background: var(--bg);
  border: 1px solid var(--border); border-radius: 6px;
}
.filters .check { display: flex; align-items: center; gap: .4rem; padding-bottom: .5rem; }
.filters .check label { margin: 0; color: var(--text); }
@media (max-width: 800px) { .filters { grid-template-columns: 1fr 1fr; } .filters .search { grid-column: 1 / -1; } }
.pub-list { padding-left: 2.6rem; }
.pub-list li { margin-bottom: .8rem; }
.pub-list li[hidden], .pub-block[hidden] { display: none; }
.count { color: var(--muted); font-size: .95rem; }
.jump { display: flex; flex-wrap: wrap; gap: .5rem 1rem; margin: 0 0 1rem; padding: 0; list-style: none; }

.site-footer { border-top: 1px solid var(--border); padding: 1.5rem 0 2.5rem; color: var(--muted); font-size: .9rem; }
.to-top { float: right; }
noscript .card { margin-top: 1rem; }
@media print {
  .site-header, .filters, .skip-link, .to-top { display: none; }
  details { border: 0; } details > summary { display: none; }
}