:root {
  --bg: #f4f6fb;
  --surface: #ffffff;
  --surface-soft: #f9fbfe;
  --surface-tint: #eef3fb;
  --text: #172033;
  --muted: #556176;
  --line: #dbe3ef;
  --accent: #1d4f91;
  --accent-2: #2b6cb0;
  --accent-dark: #11294c;
  --chip: #edf4ff;
  --success: #1f6f4a;
  --shadow: 0 18px 40px rgba(16, 31, 58, 0.08);
  --shadow-soft: 0 10px 24px rgba(16, 31, 58, 0.06);
  --radius: 20px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(43, 108, 176, 0.08), transparent 26%),
    linear-gradient(180deg, #f8fbff 0%, var(--bg) 30%, var(--bg) 100%);
  line-height: 1.7;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; display: block; }

.wrap { max-width: 1180px; margin: 0 auto; padding: 0 28px; }

.site-header {
  background: linear-gradient(135deg, #0f2241 0%, #173a6c 52%, #245da8 100%);
  color: #fff;
  padding: 22px 0 72px;
  position: relative;
  overflow: hidden;
}
.site-header:before,
.site-header:after {
  content: "";
  position: absolute;
  border-radius: 999px;
  background: rgba(255,255,255,.08);
  filter: blur(2px);
}
.site-header:before { width: 320px; height: 320px; right: -80px; top: -120px; }
.site-header:after { width: 220px; height: 220px; left: -60px; bottom: -80px; }

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 42px;
  font-size: 0.95rem;
  padding: 14px 18px;
  border: 1px solid rgba(255,255,255,.16);
  background: rgba(255,255,255,.08);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-radius: 18px;
  position: sticky;
  top: 14px;
  z-index: 20;
}
.navbar .brand {
  font-weight: 800;
  letter-spacing: 0.02em;
  color: #fff;
  font-size: 1rem;
}
.navbar .links { display: flex; flex-wrap: wrap; gap: 16px; justify-content: flex-end; }
.navbar a { color: #fff; opacity: 0.95; }
.navbar a:hover { opacity: 1; text-decoration: none; }

.hero {
  display: grid;
  grid-template-columns: minmax(0,1.15fr) minmax(250px, 340px);
  gap: 44px;
  align-items: center;
}
.hero h1 { font-size: clamp(2.6rem, 6vw, 4.25rem); line-height: 1.04; margin: 0 0 16px; letter-spacing: -0.03em; }
.hero .subtitle {
  font-size: clamp(1.05rem, 2vw, 1.32rem);
  color: #dce7fb;
  margin: 0 0 24px;
  line-height: 1.55;
}
.hero p { color: #edf4ff; font-size: 1.06rem; max-width: 760px; }
.hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  padding: 7px 12px;
  border-radius: 999px;
  background: rgba(255,255,255,.14);
  color: #dfeaff;
  font-size: 0.83rem;
  font-weight: 750;
  letter-spacing: .05em;
  text-transform: uppercase;
}
.hero-card {
  position: relative;
}
.portrait {
  width: min(100%, 320px);
  aspect-ratio: 4 / 5;
  border-radius: 28px;
  object-fit: cover;
  object-position: center top;
  border: 1px solid rgba(255,255,255,.18);
  box-shadow: 0 28px 48px rgba(0,0,0,.25);
  background: #fff;
  margin-left: auto;
}
.hero-photo-caption {
  margin-top: 12px;
  margin-left: auto;
  width: min(100%, 320px);
  color: #d8e5fb;
  font-size: .9rem;
  text-align: center;
}

.buttons { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 11px 16px;
  border-radius: 999px;
  background: #fff;
  color: var(--accent-dark);
  font-weight: 700;
  border: 1px solid rgba(255,255,255,.5);
  transition: transform .15s ease, box-shadow .15s ease;
}
.button:hover { text-decoration: none; transform: translateY(-1px); box-shadow: var(--shadow-soft); }
.button.secondary { background: rgba(255,255,255,.12); color: #fff; }
.button.secondary:hover { background: rgba(255,255,255,.18); }

.hero-meta {
  display: grid;
  grid-template-columns: repeat(4, minmax(0,1fr));
  gap: 14px;
  margin-top: 28px;
}
.stat-card {
  padding: 16px 18px;
  border-radius: 18px;
  background: rgba(255,255,255,.12);
  border: 1px solid rgba(255,255,255,.16);
  backdrop-filter: blur(12px);
}
.stat-card strong {
  display: block;
  font-size: 1.15rem;
  color: #fff;
  margin-bottom: 4px;
}
.stat-card span {
  color: #dce8ff;
  font-size: .92rem;
  line-height: 1.45;
}

main.wrap { margin-top: -36px; padding-bottom: 56px; }
section {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 22px;
  box-shadow: var(--shadow);
}
section.soft { background: linear-gradient(180deg, #ffffff 0%, #fbfdff 100%); }
section.highlight { background: linear-gradient(180deg, #fbfdff 0%, #f4f8ff 100%); }
h2 { margin: 0 0 14px; font-size: 1.6rem; line-height: 1.22; letter-spacing: -0.02em; }
h3 { margin: 22px 0 8px; font-size: 1.06rem; }
p { margin: 0 0 14px; }
ul { margin: 0; padding-left: 21px; }
li { margin: 8px 0; }
.section-lead { color: var(--muted); max-width: 900px; }

.grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 22px; }
.cards { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.card {
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px;
  background: var(--surface-soft);
  box-shadow: var(--shadow-soft);
}
.card h3 { margin-top: 0; }
.card p:last-child { margin-bottom: 0; }
.chips { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 14px; }
.chip { background: var(--chip); border: 1px solid #d5e4ff; color: #1c427b; border-radius: 999px; padding: 6px 10px; font-size: .92rem; font-weight: 600; }
.meta { color: var(--muted); }

.callout-band {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: 18px;
  align-items: stretch;
}
.band-panel {
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px;
  background: var(--surface-soft);
}
.band-panel strong { color: var(--accent-dark); }

.pubs { counter-reset: pubs; padding-left: 0; list-style: none; }
.pubs li { position: relative; padding-left: 44px; margin: 0 0 14px; }
.pubs li:before {
  counter-increment: pubs;
  content: counter(pubs);
  position: absolute;
  left: 0;
  top: 0.1rem;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--chip);
  color: var(--accent-dark);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: .88rem;
}

.people-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.person {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px;
  background: var(--surface-soft);
}
.person h3 { margin: 0 0 6px; }
.person p { margin-bottom: 6px; }

.compact-list {
  columns: 2;
  column-gap: 28px;
  margin: 12px 0 18px;
}
.course-list {
  list-style: none;
  padding-left: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}
.course-list li {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px 18px;
  background: var(--surface-soft);
  font-weight: 650;
  box-shadow: var(--shadow-soft);
}
.inline-link { font-weight: 700; }

.contact-grid, .contact-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.contact-card {
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--surface-soft);
}
footer { color: var(--muted); text-align: center; padding: 30px 0 54px; font-size: .95rem; }

@media (max-width: 980px) {
  .hero-meta { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .callout-band { grid-template-columns: 1fr; }
}

@media (max-width: 840px) {
  .wrap { padding: 0 18px; }
  .navbar { align-items: flex-start; flex-direction: column; position: static; }
  .hero { grid-template-columns: 1fr; }
  .portrait, .hero-photo-caption { margin-left: 0; }
  .grid, .cards, .contact-grid, .people-list, .course-list, .contact-cards { grid-template-columns: 1fr; }
  .compact-list { columns: 1; }
  .hero-meta { grid-template-columns: 1fr; }
  section { padding: 24px; }
}

/* Course detail pages */
.compact-header { padding-bottom: 50px; }
.page-title { max-width: 860px; padding-bottom: 16px; }
.page-title h1 { font-size: clamp(2.2rem, 5vw, 3.7rem); line-height: 1.08; margin: 0 0 16px; letter-spacing: -0.03em; }
.page-title .subtitle { color: #dce8ff; font-size: clamp(1.05rem, 2vw, 1.32rem); margin: 0; }
.eyebrow { text-transform: uppercase; letter-spacing: .11em; font-size: .78rem; font-weight: 800; color: #bcd3ff; margin: 0 0 10px; }
.course-page section.notice { background: #fff8e8; border-color: #f2d899; color: #4c3a13; }
.two-col { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.three-col { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.four-col { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.timeline { display: grid; gap: 14px; }
.timeline-item { border-left: 4px solid var(--accent); background: var(--surface-soft); border-radius: 0 14px 14px 0; padding: 16px 18px; border-top: 1px solid var(--line); border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.timeline-item h3 { margin-top: 0; }
.metric-card { text-align: left; }
.metric { display: inline-block; font-size: 1.9rem; font-weight: 800; color: var(--accent-dark); margin-bottom: 8px; }
.deliverables { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; margin-top: 14px; }
.deliverables div { border: 1px solid var(--line); border-radius: 14px; padding: 16px; background: var(--surface-soft); }
pre { background: #0e1726; color: #edf4ff; padding: 18px; border-radius: 14px; overflow-x: auto; font-size: .92rem; line-height: 1.5; }
code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace; }
.resource-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.resource-grid a { border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; background: var(--surface-soft); font-weight: 650; }
.light-button { background: var(--accent); color: #fff; }

@media (max-width: 840px) {
  .two-col, .three-col, .four-col, .deliverables, .resource-grid { grid-template-columns: 1fr; }
}

/* Data science course page helpers */
.table-wrap { overflow-x: auto; margin: 14px 0 18px; }
.syllabus-table { width: 100%; border-collapse: collapse; background: var(--surface-soft); border: 1px solid var(--line); border-radius: 14px; overflow: hidden; }
.syllabus-table th, .syllabus-table td { border: 1px solid var(--line); padding: 12px 14px; vertical-align: top; text-align: left; }
.syllabus-table th { background: var(--chip); color: var(--accent-dark); font-weight: 800; }
details { border: 1px solid var(--line); background: var(--surface-soft); border-radius: 14px; padding: 14px 18px; margin: 12px 0; }
details summary { cursor: pointer; font-weight: 800; color: var(--accent-dark); }
details ol { margin-top: 12px; }
code { background: #eef4ff; border: 1px solid #d5e4ff; border-radius: 6px; padding: 0 4px; }
.light-button { background: var(--chip); color: var(--accent-dark); border: 1px solid #d5e4ff; }