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

:root {
  --bg:        #0a5242;
  --surface:   #0F6E56;
  --surface2:  rgba(255,255,255,0.07);
  --border:    rgba(255,255,255,0.12);
  --accent:    #5DDAB4;
  --accent-dim:#A8E8D4;
  --text:      #fff;
  --text-muted:#C8EDE3;
  --text-dim:  #88C9B8;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

/* ── Nav ── */
nav {
  background: rgba(10,82,66,0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 0 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}
.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
}
.nav-brand em { font-style: normal; color: var(--accent); }
.nav-logo {
  width: 28px; height: 28px;
  background: var(--accent);
  border-radius: 6px;
  display: flex; align-items: center; justify-content: center;
}
.nav-links {
  display: flex;
  gap: 4px;
  list-style: none;
}
.nav-links a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 13.5px;
  font-weight: 500;
  padding: 6px 12px;
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}
.nav-links a:hover, .nav-links a.active {
  background: var(--surface2);
  color: var(--text);
}

/* ── Hero ── */
.hero {
  background: var(--surface);
  padding: 60px 40px 50px;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}
.hero-bg-art {
  position: absolute;
  top: 0; right: 0;
  pointer-events: none;
  opacity: 0.1;
}
.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255,255,255,0.1);
  color: var(--accent-dim);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 5px 14px;
  border-radius: 20px;
  margin-bottom: 20px;
}
.hero-eyebrow::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
}
.hero h1 {
  font-size: 56px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  margin-bottom: 10px;
}
.hero h1 em { font-style: normal; color: var(--accent); }
.hero-tagline {
  font-size: 16px;
  color: var(--accent-dim);
  margin-bottom: 28px;
}
.hero-pills {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
.pill {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.18);
  color: #E8F9F4;
  font-size: 14px;
  font-weight: 500;
  padding: 6px 14px;
  border-radius: 8px;
}
.pill svg { opacity: 0.8; flex-shrink: 0; }

/* ── Main layout ── */
main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 40px 40px 80px;
}

/* ── Section header ── */
.section-label {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 16px;
}
.week-header {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 16px;
  margin-top: 36px;
}
.week-header h2 {
  font-size: 20px;
  font-weight: 700;
}
.week-header span {
  font-size: 13px;
  color: var(--text-dim);
}

/* ── Legend ── */
.legend {
  display: flex;
  gap: 16px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}
.legend-item {
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 12.5px;
  color: var(--text-muted);
}
.legend-dot {
  width: 10px; height: 10px;
  border-radius: 3px;
  flex-shrink: 0;
}
.legend-dot.lecture  { background: rgba(93,218,180,0.35); border: 1px solid var(--accent); }
.legend-dot.tutorial { background: rgba(255,180,50,0.25);  border: 1px solid #FFB432; }
.legend-dot.free     { background: rgba(255,255,255,0.08); border: 1px solid var(--border); }

/* ── Schedule grid ── */
.schedule-grid {
  display: grid;
  grid-template-columns: 90px repeat(5, 1fr);
  gap: 4px;
  margin-bottom: 8px;
}
.grid-header {
  font-size: 11.5px;
  font-weight: 600;
  color: var(--text-dim);
  text-align: center;
  padding: 8px 4px;
  letter-spacing: 0.04em;
}
.grid-header.time-col { text-align: left; color: transparent; }
.grid-header .date {
  display: block;
  font-size: 10px;
  font-weight: 400;
  color: var(--text-dim);
  margin-top: 2px;
  letter-spacing: 0;
}

.time-slot {
  font-size: 11px;
  color: var(--text-dim);
  padding: 8px 4px;
  display: flex;
  align-items: center;
}

/* ── Session cards ── */
.session {
  border-radius: 8px;
  padding: 10px 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-height: 72px;
  text-decoration: none;
  transition: filter 0.15s, transform 0.12s;
  position: relative;
  border: 1px solid transparent;
}
.session:hover {
  filter: brightness(1.12);
  transform: translateY(-1px);
}
.session.lecture {
  background: rgba(93,218,180,0.12);
  border-color: rgba(93,218,180,0.3);
}
.session.tutorial {
  background: rgba(255,180,50,0.12);
  border-color: rgba(255,180,50,0.3);
}
.session.introductions {
  background: rgba(123, 192, 255, 0.14);
  border-color: rgba(123, 192, 255, 0.35);
}
.session.free {
  background: var(--surface2);
  border-color: var(--border);
  cursor: default;
}
.session.free:hover { filter: none; transform: none; }
.session.span2 { grid-row: span 2; min-height: 152px; }

.session-type {
  font-size: 9.5px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}
.lecture  .session-type { color: var(--accent); }
.tutorial .session-type { color: #FFB432; }
.introductions .session-type { color: #7BC0FF; }
.free     .session-type { color: var(--text-dim); }

.session-title {
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  line-height: 1.35;
}
.session-sub {
  font-size: 10.5px;
  color: var(--text-muted);
  margin-top: auto;
}
.session-instructor {
  font-size: 11px;
  color: var(--accent-dim);
  display: flex;
  align-items: center;
  gap: 5px;
  margin-top: auto;
  padding-top: 6px;
}
.session-instructor svg { opacity: 0.7; flex-shrink: 0; }
.session-instructor a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid rgba(168,232,212,0.3);
  transition: border-color 0.15s, color 0.15s;
}
.session-instructor a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.session-link-icon {
  position: absolute;
  top: 8px; right: 8px;
  opacity: 0;
  transition: opacity 0.15s;
}
.session:hover .session-link-icon { opacity: 0.6; }

/* ── Divider ── */
hr.divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 32px 0;
}

/* ── Footer ── */
footer {
  background: rgba(0,0,0,0.2);
  border-top: 1px solid var(--border);
  padding: 20px 40px;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--text-dim);
}
footer .sep { color: var(--border); }

/* ── Hackathon cards ── */
.session.hackathon {
  background: rgba(99,179,237,0.12);
  border-color: rgba(99,179,237,0.35);
}
.session.hackathon:hover { filter: brightness(1.1); transform: translateY(-1px); }
.hackathon .session-type { color: #63B3ED; }

/* ── Break rows ── */
.break-row {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 3px 0;
  font-size: 10.5px;
  color: var(--text-dim);
  letter-spacing: 0.04em;
}
.break-row .break-label {
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: 6px;
}
.break-row::before, .break-row::after {
  content: '';
  flex: 1;
  border-top: 1px dashed rgba(255,255,255,0.1);
}

/* ── Responsive ── */
@media (max-width: 800px) {
  nav { padding: 0 20px; }
  .hero { padding: 40px 20px 36px; }
  .hero h1 { font-size: 38px; }
  main { padding: 24px 20px 60px; }
  .schedule-grid { grid-template-columns: 70px repeat(5, 1fr); font-size: 11px; }
  .session-title { font-size: 10.5px; }
}