/* ── Bi 122 · Genetics ─────────────────────────────────────────────── */

:root {
  --background: #f7f7f5;
  --panel: #ffffff;
  --surface: #f3f3f1;
  --surface-hover: #ececea;
  --ink: #111111;
  --muted: #747474;
  --muted-strong: #3f3f3f;
  --border: #dededb;
  --border-soft: #ececea;
  --danger: #b42318;
  --shadow: 0 10px 32px rgba(17, 17, 17, 0.055);
  --panel-shadow: 0 8px 28px rgba(0, 0, 0, 0.035);
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
  --serif: Charter, "Bitstream Charter", "Iowan Old Style", "Palatino Linotype",
    Palatino, "Book Antiqua", Georgia, ui-serif, serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 76px;
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--background);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 13.5px;
  line-height: 1.5;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection {
  background: #ddddda;
}

a {
  color: var(--ink);
  text-decoration: none;
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
  border-radius: 3px;
}

/* ── Shell ─────────────────────────────────────────────────────────── */

.shell {
  max-width: 1060px;
  margin: 0 auto;
  padding: 0 28px 40px;
}

/* ── Nav ───────────────────────────────────────────────────────────── */

.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(247, 247, 245, 0.9);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: 1060px;
  margin: 0 auto;
  padding: 10px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.nav-mark {
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.nav-mark span {
  font-family: var(--sans);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--muted);
  margin-left: 9px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2px;
  flex-wrap: wrap;
}

.nav-links a {
  display: inline-flex;
  align-items: center;
  height: 32px;
  padding: 0 11px;
  border-radius: 8px;
  font-size: 12.5px;
  font-weight: 650;
  letter-spacing: -0.01em;
  color: var(--muted-strong);
  transition: background 0.18s var(--ease), color 0.18s var(--ease);
}

.nav-links a:hover {
  background: var(--surface-hover);
  color: var(--ink);
}

.nav-links a.canvas {
  margin-left: 6px;
  background: var(--ink);
  color: #fff;
  font-weight: 700;
  padding: 0 13px;
}

.nav-links a.canvas:hover {
  background: #000;
  color: #fff;
}

/* ── Masthead ──────────────────────────────────────────────────────── */

.masthead {
  padding: 52px 0 30px;
  border-bottom: 2px solid var(--ink);
}

.eyebrow {
  font-size: 10.5px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.masthead h1 {
  font-family: var(--serif);
  margin: 14px 0 0;
  font-size: clamp(34px, 6vw, 54px);
  font-weight: 700;
  letter-spacing: -0.028em;
  line-height: 1.02;
}

.masthead .lede {
  margin: 14px 0 0;
  max-width: 60ch;
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.55;
  color: var(--muted-strong);
}

.meta-row {
  display: flex;
  flex-wrap: wrap;
  margin: 28px 0 0;
  background: var(--panel);
  border: 1px solid var(--border-soft);
  border-radius: 12px;
  overflow: hidden;
}

.meta-cell {
  flex: 1 1 138px;
  padding: 12px 15px;
  border-left: 1px solid var(--border-soft);
}

.meta-cell:first-child {
  border-left: 0;
}

.meta-cell dt {
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.meta-cell dd {
  margin: 4px 0 0;
  font-size: 13.5px;
  font-weight: 700;
  letter-spacing: -0.015em;
}

/* ── Sections ──────────────────────────────────────────────────────── */

.section {
  padding-top: 44px;
}

.section-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
  padding-bottom: 10px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--border);
}

.section h2 {
  font-family: var(--serif);
  margin: 0;
  font-size: 25px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.section-note {
  font-size: 12px;
  font-weight: 650;
  color: var(--muted);
}

/* ── Panels ────────────────────────────────────────────────────────── */

.panel {
  background: var(--panel);
  border: 1px solid #e5e5e5;
  border-radius: 14px;
  box-shadow: var(--panel-shadow);
  overflow: hidden;
}

.panel-pad {
  padding: 20px 22px;
}

.prose p {
  margin: 0 0 12px;
  color: var(--muted-strong);
  max-width: 76ch;
}

.prose p:last-child {
  margin-bottom: 0;
}

.prose strong {
  color: var(--ink);
  font-weight: 700;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.sub {
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 10px;
}

/* ── People ────────────────────────────────────────────────────────── */

.people {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(196px, 1fr));
  gap: 14px;
}

.person {
  display: flex;
  gap: 13px;
  align-items: center;
  padding: 13px;
  background: var(--panel);
  border: 1px solid #e5e5e5;
  border-radius: 12px;
  box-shadow: var(--panel-shadow);
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.person:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.person img {
  flex: none;
  width: 56px;
  height: 74px;
  object-fit: cover;
  border-radius: 8px;
  background: var(--surface);
  border: 1px solid var(--border-soft);
}

.person.lead {
  border-color: #d6d6d3;
}

.person.lead .person-role {
  color: var(--ink);
}

.person-role {
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--muted);
}

.person-name {
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.015em;
  margin-top: 2px;
}

.person-mail {
  display: block;
  margin-top: 3px;
  font-size: 11.5px;
  font-weight: 600;
  color: var(--muted);
  word-break: break-word;
  transition: color 0.18s var(--ease);
}

.person-mail:hover {
  color: var(--ink);
}

.alumni {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

.alum {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 13px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--panel);
  font-size: 12.5px;
  font-weight: 650;
}

.alum span {
  font-size: 11px;
  color: var(--muted);
  font-weight: 600;
}

/* ── Materials ─────────────────────────────────────────────────────── */

.wk {
  border-bottom: 1px solid var(--border-soft);
}

.wk:last-child {
  border-bottom: 0;
}

.wk-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 11px 20px 7px;
  background: #fbfbfa;
  border-bottom: 1px solid var(--border-soft);
}

.wk-num {
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.file {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 11px 20px;
  border-bottom: 1px solid #f4f4f2;
  transition: background 0.15s var(--ease);
}

.file:last-child {
  border-bottom: 0;
}

.file:hover {
  background: #fafafa;
}

.file-thumb {
  flex: none;
  width: 54px;
  height: 40px;
  object-fit: contain;
  border-radius: 4px;
  border: 1px solid var(--border);
  background: #fff;
}

.file-name {
  font-size: 13.5px;
  font-weight: 700;
  letter-spacing: -0.015em;
  flex: 1;
  min-width: 0;
}

.file-name .rev {
  display: inline-block;
  margin-left: 8px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  vertical-align: 1px;
}

.file-meta {
  flex: none;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--muted);
  white-space: nowrap;
}

.file-dl {
  flex: none;
  font-size: 11.5px;
  font-weight: 700;
  color: var(--muted);
  padding: 5px 10px;
  border-radius: 8px;
  border: 1px solid transparent;
  transition: all 0.15s var(--ease);
}

.file:hover .file-dl {
  color: var(--ink);
  border-color: var(--border);
  background: var(--panel);
}

/* ── Tables ────────────────────────────────────────────────────────── */

.table-scroll {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 600px;
}

thead th {
  text-align: left;
  padding: 11px 18px;
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  background: #fbfbfa;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

tbody td {
  padding: 11px 18px;
  border-bottom: 1px solid #f4f4f2;
  vertical-align: top;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted-strong);
}

tbody tr:last-child td {
  border-bottom: 0;
}

tbody tr:hover td {
  background: #fafafa;
}

td.week {
  font-size: 10.5px;
  font-weight: 800;
  letter-spacing: 0.07em;
  color: var(--muted);
  white-space: nowrap;
}

td.date {
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}

td.topic {
  font-weight: 700;
  color: var(--ink);
  letter-spacing: -0.015em;
}

td.reading {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--muted);
  white-space: nowrap;
}

td.num {
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--ink);
}

.rule td {
  border-top: 1px solid var(--border);
}

.tag {
  display: inline-block;
  padding: 3px 9px;
  border-radius: 999px;
  font-size: 10.5px;
  font-weight: 700;
  white-space: nowrap;
  background: var(--ink);
  border: 1px solid var(--ink);
  color: #fff;
}

.tag.exam {
  background: #fef2f2;
  border-color: #f4c9c9;
  color: #a62016;
}

.row-off td.topic {
  color: var(--muted);
  font-weight: 650;
}

/* ── Stat strip ────────────────────────────────────────────────────── */

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  background: var(--border-soft);
}

.stat {
  background: var(--panel);
  padding: 18px 20px;
}

.stat-value {
  font-family: var(--serif);
  font-size: clamp(26px, 4.5vw, 34px);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1;
}

.stat-label {
  margin-top: 7px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.stat-sub {
  margin-top: 2px;
  font-size: 11px;
  font-weight: 600;
  color: var(--muted);
}

.scale {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 12px;
}

.grade {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid #e0e0e0;
  font-size: 12px;
  font-weight: 650;
}

.grade b {
  font-weight: 800;
}

/* ── Callout ───────────────────────────────────────────────────────── */

.callout {
  display: flex;
  gap: 11px;
  padding: 13px 16px;
  border-radius: 11px;
  background: #fff8ec;
  border: 1px solid #f0dcb4;
  color: #7a5200;
  font-size: 12.5px;
  font-weight: 620;
  margin-top: 14px;
}

.callout::before {
  content: "";
  flex: none;
  width: 7px;
  height: 7px;
  margin-top: 6px;
  border-radius: 999px;
  background: #b7791f;
}

.callout-tag {
  display: block;
  font-weight: 800;
  font-size: 9.5px;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  margin-bottom: 2px;
}

.callout.plain {
  background: var(--surface);
  border-color: var(--border);
  color: var(--muted-strong);
}

.callout.plain::before {
  background: var(--muted);
}

/* ── Book ──────────────────────────────────────────────────────────── */

.book {
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.book-spine {
  flex: none;
  width: 40px;
  height: 56px;
  border-radius: 3px 7px 7px 3px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 4px solid var(--ink);
}

.book-title {
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.015em;
}

.book-meta {
  margin-top: 3px;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--muted);
}

.isbn {
  display: inline-block;
  margin-top: 8px;
  padding: 3px 8px;
  border-radius: 6px;
  background: var(--surface);
  border: 1px solid var(--border-soft);
  font-family: var(--mono);
  font-size: 10.5px;
  color: var(--muted-strong);
}

/* ── Document viewer ───────────────────────────────────────────────── */

.viewer {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: flex;
  flex-direction: column;
  padding: 22px;
  gap: 12px;
  background: rgba(24, 24, 22, 0.55);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  animation: viewer-in 0.2s var(--ease);
}

.viewer[hidden] {
  display: none;
}

@keyframes viewer-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}

.viewer-bar {
  flex: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
}

.viewer-title {
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: #fff;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.viewer-actions {
  flex: none;
  display: flex;
  gap: 7px;
}

.vbtn {
  display: inline-flex;
  align-items: center;
  height: 32px;
  padding: 0 13px;
  border-radius: 9px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  background: transparent;
  color: #fff;
  font-family: var(--sans);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: -0.01em;
  cursor: pointer;
  transition: background 0.15s var(--ease), border-color 0.15s var(--ease);
}

.vbtn:hover {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.5);
}

.vbtn.solid {
  background: #fff;
  border-color: #fff;
  color: var(--ink);
}

.vbtn.solid:hover {
  background: #ececea;
}

.viewer:focus-visible,
.vbtn:focus-visible {
  outline: 2px solid #fff;
  outline-offset: 3px;
}

.viewer-body {
  flex: 1;
  min-height: 0;
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
  border-radius: 12px;
  overflow: hidden;
  background: var(--panel);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.3);
}

.viewer-body iframe {
  width: 100%;
  height: 100%;
  border: 0;
  display: block;
}

@media (max-width: 640px) {
  .viewer {
    padding: 12px;
    gap: 9px;
  }
  .viewer-title {
    font-size: 14px;
  }
  .vbtn {
    height: 34px;
    padding: 0 11px;
    font-size: 12px;
  }
  #viewerTab {
    display: none;
  }
}

/* ── Footer ────────────────────────────────────────────────────────── */

.footer {
  margin-top: 48px;
  border-top: 2px solid var(--ink);
  padding: 18px 0 0;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 11.5px;
  font-weight: 650;
  color: var(--muted);
}

/* ── Responsive ────────────────────────────────────────────────────── */

@media (max-width: 900px) {
  .nav-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
  .grid-2 {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .shell {
    padding: 0 16px 32px;
  }
  .nav-inner {
    padding: 9px 16px;
  }
  .masthead {
    padding: 30px 0 24px;
  }
  .panel-pad {
    padding: 16px;
  }
  .file,
  .wk-head {
    padding-left: 14px;
    padding-right: 14px;
  }
  .file-meta {
    display: none;
  }
  .stat {
    padding: 15px 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}