/* ---------------------------------------------------------------
   Design tokens
   Subject: course-catalog browsing, in the vernacular of a library
   card catalog / registrar index card. Quiet, paper-toned, with a
   single accent color and a monospace "call number" treatment for
   course codes and meeting times.
------------------------------------------------------------------ */
:root {
  --paper: #faf9f6;
  --paper-raised: #ffffff;
  --ink: #1b1a18;
  --oxblood: #7a2330;
  --oxblood-dim: #9c4a55;
  --slate: #6e6a63;
  --slate-light: #99948b;
  --charcoal: #3a3733;
  --hairline: #dedad2;
  --mist: #f2f0eb;

  --font-mono: 'IBM Plex Mono', ui-monospace, 'SF Mono', Consolas, monospace;
  --font-serif: 'Source Serif 4', Georgia, 'Times New Roman', serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  --radius: 3px;
  --dur: 220ms;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

@media (prefers-reduced-motion: reduce) {
  :root { --dur: 1ms; }
  * { animation-duration: 1ms !important; transition-duration: 1ms !important; }
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
}

body { min-height: 100vh; }

a { color: var(--oxblood); text-decoration: none; }
a:hover { text-decoration: underline; }

.tile-instructors a,
.section-instructor a {
  color: var(--ink);
}

button {
  font-family: inherit;
  cursor: pointer;
}

:focus-visible {
  outline: 2px solid var(--oxblood);
  outline-offset: 2px;
}

/* -------------------- Filter bar -------------------- */

.filterbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: var(--paper);
  border-bottom: 1px solid var(--hairline);
}

.filterbar-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 18px 28px 14px;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 14px;
}

.brand-mark {
  font-family: var(--font-mono);
  color: var(--oxblood);
  font-size: 14px;
  letter-spacing: 0.04em;
}

.brand h1 {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 21px;
  margin: 0;
  letter-spacing: -0.01em;
}

.controls {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.control-row {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: 24px;
  row-gap: 12px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  position: relative;
}

.field > label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--slate);
  font-weight: 500;
}

#searchInput {
  font-family: var(--font-sans);
  font-size: 14px;
  padding: 8px 12px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  background: var(--paper-raised);
  color: var(--ink);
  width: 260px;
  max-width: 100%;
}

#searchInput:focus {
  border-color: var(--oxblood-dim);
}

.ms-trigger {
  font-family: var(--font-sans);
  font-size: 14px;
  text-align: left;
  padding: 7px 30px 7px 10px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  background: var(--paper-raised) url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="10" height="6"><path d="M0 0L5 6L10 0Z" fill="%236E6A63"/></svg>') no-repeat right 10px center;
  color: var(--ink);
  min-width: 168px;
  position: relative;
}

.ms-trigger.has-selection {
  border-color: var(--oxblood-dim);
  color: var(--oxblood);
}

.msfield.open .ms-trigger {
  border-color: var(--oxblood);
}

.ms-panel {
  display: none;
  position: absolute;
  top: calc(100% + 6px);
  left: 0;
  min-width: 220px;
  max-height: 280px;
  overflow-y: auto;
  background: var(--paper-raised);
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  box-shadow: 0 6px 20px rgba(27, 26, 24, 0.10);
  padding: 6px;
  z-index: 30;
}

.msfield.open .ms-panel { display: block; }

.ms-option {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px;
  border-radius: 2px;
  font-size: 13.5px;
  cursor: pointer;
  white-space: nowrap;
}

.ms-option:hover { background: var(--mist); }

.ms-option input { accent-color: var(--oxblood); }

.daysfield .days {
  display: flex;
  gap: 4px;
}

.day {
  display: inline-flex;
}

.day input { position: absolute; opacity: 0; width: 1px; height: 1px; }

.day span {
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 12px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  color: var(--slate);
  background: var(--paper-raised);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.day input:checked + span {
  background: var(--oxblood);
  border-color: var(--oxblood);
  color: #fff;
}

.day input:focus-visible + span {
  outline: 2px solid var(--oxblood);
  outline-offset: 2px;
}

.toggle-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.toggle-btn {
  display: inline-flex;
}

.toggle-btn input { position: absolute; opacity: 0; width: 1px; height: 1px; }

.toggle-btn span {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 7px 12px;
  font-family: var(--font-sans);
  font-size: 13px;
  white-space: nowrap;
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  color: var(--slate);
  background: var(--paper-raised);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.toggle-btn input:checked + span {
  background: var(--oxblood);
  border-color: var(--oxblood);
  color: #fff;
}

.toggle-btn input:focus-visible + span {
  outline: 2px solid var(--oxblood);
  outline-offset: 2px;
}

.clear-btn {
  background: var(--paper-raised);
  border: 1px solid var(--oxblood);
  border-radius: var(--radius);
  color: var(--oxblood);
  font-size: 13px;
  font-weight: 500;
  padding: 7px 14px;
  margin-left: auto;
  align-self: flex-end;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.clear-btn:hover {
  background: var(--oxblood);
  color: #fff;
}

.view-bar {
  display: flex;
  align-items: flex-end;
  gap: 20px;
  margin-top: 12px;
}


.count {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.03em;
  color: var(--slate-light);
  margin-left: auto;
  padding-bottom: 1px;
}

/* -------------------- Compact column view -------------------- */

.compact-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  overflow: hidden;
}

.compact-cols:has(.compact-col:nth-child(4)) {
  grid-template-columns: repeat(4, 1fr);
}

.compact-col {
  border-right: 1px solid var(--hairline);
  min-width: 0;
}

.compact-col:last-child { border-right: none; }

.compact-col-header {
  font-family: var(--font-sans);
  font-size: 10.5px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--season-accent, var(--slate));
  background: var(--season-tint, var(--mist));
  padding: 7px 10px 6px;
  border-bottom: 1px solid var(--hairline);
}

.compact-col-empty {
  padding: 10px;
  font-size: 11px;
  color: var(--slate-light);
  font-style: italic;
}

.compact-token {
  padding: 3px 10px 3px;
  border-bottom: 1px solid var(--hairline);
  cursor: pointer;
  transition: background var(--dur) var(--ease);
}

.compact-token:last-child { border-bottom: none; }

.compact-token:hover { background: var(--season-tint, var(--mist)); }

.compact-code {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  color: var(--season-accent, var(--oxblood));
}

.compact-title {
  font-size: 11px;
  color: var(--ink);
  line-height: 1.35;
}

.compact-inst {
  display: none;
  font-size: 10.5px;
  color: var(--slate);
  padding: 1px 0 2px;
}

.compact-token.open .compact-inst { display: block; }

.compact-section-line {
  display: grid;
  grid-template-columns: 3.5em 1fr auto;
  gap: 0 8px;
  align-items: baseline;
  padding: 1px 0;
}

.compact-sec-num {
  font-family: var(--font-mono);
  font-size: 9.5px;
  color: var(--slate-light);
  white-space: nowrap;
}

.compact-sec-instr {
  font-size: 10.5px;
  color: var(--slate);
}

.compact-sec-meets {
  font-family: var(--font-mono);
  font-size: 9.5px;
  color: var(--ink);
  white-space: nowrap;
}

/* -------------------- Grid & tiles -------------------- */

main {
  max-width: 1280px;
  margin: 0 auto;
  padding: 28px 28px 80px;
}

.grid {
  position: relative;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(252px, 1fr));
  gap: 16px;
  align-items: start;
}

.empty {
  font-family: var(--font-serif);
  font-size: 16px;
  color: var(--slate);
  text-align: center;
  padding: 60px 0;
}

.tile {
  background: var(--season-tint, var(--paper-raised));
  border: 1px solid var(--hairline);
  border-left: 4px solid var(--season-accent, var(--oxblood));
  border-radius: var(--radius);
  padding: 14px 16px 16px;
  cursor: pointer;
  transition: box-shadow var(--dur) var(--ease), border-color var(--dur) var(--ease),
              opacity var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.tile:hover {
  box-shadow: 0 6px 18px rgba(27, 26, 24, 0.10);
  border-color: var(--season-accent, var(--slate-light));
}

.tile.expanded {
  grid-column: span 2;
  cursor: default;
}

.tile.hidden-tile {
  display: none;
}

.tile.entering {
  opacity: 0;
  transform: scale(0.96);
}

.tile.leaving {
  opacity: 0;
  transform: scale(0.94);
  pointer-events: none;
}

.tile-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.tile-quarter {
  font-family: var(--font-sans);
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--season-accent, var(--slate-light));
  font-weight: 600;
  white-space: nowrap;
}

.tile-dates {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.03em;
  color: var(--season-accent, var(--slate));
  margin: 3px 0 0;
  opacity: 0.85;
}

.tile-expand-toggle {
  background: var(--paper-raised);
  border: 1px solid var(--hairline);
  border-radius: 50%;
  width: 22px;
  height: 22px;
  padding: 0;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--slate);
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1;
  flex-shrink: 0;
  cursor: pointer;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.tile.expanded .tile-expand-toggle {
  background: var(--season-accent, var(--oxblood));
  color: #fff;
  border-color: var(--season-accent, var(--oxblood));
}

.tile-title {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 16.5px;
  line-height: 1.32;
  margin: 10px 0 4px;
  color: var(--ink);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.tile.expanded .tile-title {
  -webkit-line-clamp: unset;
  overflow: visible;
}

.tile-crosslist {
  font-family: var(--font-sans);
  font-size: 11px;
  font-style: italic;
  color: var(--charcoal);
  line-height: 1.35;
  margin: 0 0 8px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.tile.expanded .tile-crosslist {
  -webkit-line-clamp: unset;
  overflow: visible;
}

.tile-rule {
  border: none;
  border-top: 1px solid rgba(27, 26, 24, 0.14);
  margin: 0 0 8px;
}

.tile-instructors {
  font-size: 12.5px;
  color: var(--slate);
  line-height: 1.4;
}

/* -------------------- Expanded detail -------------------- */

.tile-details {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows calc(var(--dur) * 1.3) var(--ease);
}

.tile.expanded .tile-details {
  grid-template-rows: 1fr;
}

.tile-details-inner {
  overflow: hidden;
  min-height: 0;
}

.detail-block {
  padding-top: 14px;
  margin-top: 10px;
  border-top: 1px solid rgba(27, 26, 24, 0.14);
}

.detail-desig-row {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
  margin-bottom: 8px;
}

.desig-tag {
  display: inline-block;
  font-family: var(--font-sans);
  font-size: 11px;
  font-weight: 500;
  line-height: 1;
  padding: 3px 8px;
  border-radius: 2px;
  background: var(--season-tint, var(--mist));
  border: 1px solid var(--season-accent, var(--hairline));
  color: var(--season-accent, var(--charcoal));
}

.desig-note {
  font-size: 11.5px;
  font-style: italic;
  color: var(--slate);
  line-height: 1.45;
  margin-bottom: 12px;
  margin-top: -6px;
}

.detail-descrip {
  font-size: 13.5px;
  line-height: 1.55;
  color: var(--ink);
  white-space: pre-line;
}

.detail-label {
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--slate-light);
  margin-bottom: 4px;
  margin-top: 12px;
}

.detail-prereq {
  font-size: 13px;
  line-height: 1.5;
  color: var(--slate);
}

.sections {
  margin-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.section-row {
  border-top: 1px dashed rgba(27, 26, 24, 0.16);
  padding-top: 10px;
  font-size: 13px;
  line-height: 1.55;
}

.section-row:first-child {
  border-top: 1px solid rgba(27, 26, 24, 0.14);
}

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

.section-id-key {
  position: relative;
  display: inline-flex;
  align-items: center;
  margin-left: auto;
  flex-shrink: 0;
  color: var(--ink);
  cursor: default;
}

.section-id-key svg {
  display: block;
  opacity: 0.45;
  transition: opacity var(--dur) var(--ease);
}

.section-id-key:hover svg {
  opacity: 0.85;
}

.section-id-key::after {
  content: "offeringID  " attr(data-offering-id) "\A sectionID   " attr(data-section-id);
  position: absolute;
  right: 0;
  top: calc(100% + 5px);
  background: var(--charcoal);
  color: #f2f0eb;
  font-family: var(--font-mono);
  font-size: 10.5px;
  line-height: 1.7;
  white-space: pre;
  padding: 5px 10px;
  border-radius: var(--radius);
  pointer-events: none;
  opacity: 0;
  transition: opacity 120ms;
  z-index: 10;
}

.section-id-key:hover::after {
  opacity: 1;
}

.section-num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--slate-light);
}

.section-instructor a {
  font-weight: 500;
}

.section-meta {
  margin-top: 2px;
  color: var(--slate);
  font-size: 12.5px;
}

.section-meta .meets {
  font-family: var(--font-mono);
  color: var(--ink);
}

.section-labs {
  margin-top: 8px;
}

.section-labs-label {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--slate-light);
  margin-bottom: 3px;
}

.labs-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.labs-list li {
  font-size: 12px;
  color: var(--slate);
  padding-left: 13px;
  position: relative;
}

.labs-list li::before {
  content: '\2013';
  position: absolute;
  left: 0;
  color: var(--slate-light);
}

/* -------------------- Responsive -------------------- */

@media (max-width: 720px) {
  .filterbar-inner { padding: 14px 16px 12px; }
  main { padding: 20px 16px 60px; }
  .controls { gap: 12px; }
  #searchInput { width: 100%; }
  .clear-btn { margin-left: 0; }
  .tile.expanded { grid-column: span 1; }
}