:root {
  color-scheme: light;
  --bg: #f4f5f1;
  --ink: #16211f;
  --muted: #65706d;
  --line: #d8ddd5;
  --panel: #ffffff;
  --panel-soft: #f9faf7;
  --tutor: #25635d;
  --lok: #855f1c;
  --gk: #2e5f9e;
  --extra: #7552a1;
  --danger: #b94040;
  --shadow: 0 18px 40px rgba(26, 39, 37, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--bg);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

button,
input,
select {
  font: inherit;
}

button,
select,
input {
  border: 1px solid var(--line);
}

button {
  min-height: 42px;
  border-radius: 8px;
  background: var(--ink);
  color: #fff;
  cursor: pointer;
  padding: 0 14px;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

.ghost-button,
.icon-button.secondary {
  background: #fff;
  color: var(--ink);
}

.app-shell {
  width: min(1640px, 100%);
  margin: 0 auto;
  padding: 20px;
}

.topbar,
.setup-panel,
.status-strip,
.calendar-panel,
.course-browser,
.selection-panel {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.88);
  box-shadow: var(--shadow);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 18px;
  border-radius: 8px;
}

.top-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
}

h1,
h2,
p {
  margin: 0;
}

h1 {
  font-size: clamp(1.7rem, 3vw, 2.8rem);
  line-height: 1.04;
}

h2 {
  font-size: 1.18rem;
}

.eyebrow {
  color: var(--muted);
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.setup-panel {
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(220px, 1fr) auto;
  gap: 12px;
  margin-top: 14px;
  padding: 14px;
  border-radius: 8px;
  align-items: end;
}

label {
  display: grid;
  gap: 7px;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
}

select,
input[type="search"] {
  width: 100%;
  min-height: 44px;
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  padding: 0 12px;
}

.toggle-row {
  grid-template-columns: auto 1fr;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-soft);
  color: var(--ink);
}

.toggle-row input {
  width: 18px;
  height: 18px;
}

.status-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(110px, 160px)) minmax(220px, 1fr);
  gap: 12px;
  margin-top: 14px;
  padding: 12px 14px;
  border-radius: 8px;
  align-items: center;
}

.status-strip > div:not(.build-status) {
  display: grid;
  gap: 2px;
}

.status-strip strong {
  font-size: 1.6rem;
  line-height: 1;
}

.status-strip span,
.build-status {
  color: var(--muted);
  font-size: 0.88rem;
}

.build-status.ready {
  color: var(--tutor);
  font-weight: 800;
}

.build-status.warn {
  color: var(--danger);
  font-weight: 800;
}

.workspace {
  display: grid;
  grid-template-columns: 390px minmax(0, 1fr);
  gap: 16px;
  margin-top: 16px;
  align-items: start;
}

.course-browser,
.calendar-panel,
.selection-panel {
  border-radius: 8px;
}

.course-browser {
  position: sticky;
  top: 16px;
  max-height: calc(100vh - 32px);
  overflow: hidden;
  display: grid;
  grid-template-rows: auto auto minmax(0, 1fr);
}

.browser-tools {
  display: grid;
  gap: 10px;
  padding: 14px;
  border-bottom: 1px solid var(--line);
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 700;
}

.legend span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 999px;
  display: inline-block;
}

.dot.tutor { background: var(--tutor); }
.dot.lok { background: var(--lok); }
.dot.gk { background: var(--gk); }
.dot.conflict { background: var(--danger); }

.course-list {
  overflow: auto;
  padding: 10px;
}

.subject-block {
  display: grid;
  gap: 10px;
  margin-bottom: 10px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.subject-block header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.subject-block header div {
  display: grid;
  gap: 2px;
}

.subject-block header strong {
  font-size: 0.98rem;
}

.subject-block header span {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 700;
}

.course-pick {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 10px;
  align-items: center;
  min-height: 82px;
  padding: 10px;
  border: 1px solid var(--line);
  border-left: 5px solid var(--gk);
  border-radius: 8px;
  background: var(--panel-soft);
  cursor: grab;
}

.course-pick.extra {
  border-left-color: var(--extra);
}

.course-pick.empty {
  display: block;
  min-height: 0;
  border-left-color: var(--line);
  color: var(--muted);
  cursor: default;
  font-size: 0.86rem;
}

.course-pick.dragging {
  opacity: 0.4;
}

.course-pick strong,
.course-pick span,
.course-pick small {
  display: block;
  overflow-wrap: anywhere;
}

.course-pick strong {
  font-size: 0.92rem;
}

.course-pick span,
.course-pick small {
  color: var(--muted);
  font-size: 0.78rem;
  line-height: 1.35;
}

.pick-actions {
  display: grid;
  gap: 7px;
  justify-items: end;
  align-items: center;
}

.pick-actions > span {
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 900;
  text-transform: uppercase;
}

.course-card {
  display: grid;
  gap: 8px;
  width: 100%;
  margin-bottom: 10px;
  padding: 12px;
  border: 1px solid var(--line);
  border-left: 5px solid var(--gk);
  border-radius: 8px;
  background: #fff;
  cursor: grab;
}

.course-card.extra {
  border-left-color: var(--extra);
}

.course-card.is-selected {
  opacity: 0.55;
}

.course-card.dragging {
  opacity: 0.4;
}

.drag-ghost {
  position: fixed;
  z-index: 50;
  width: min(340px, calc(100vw - 32px));
  pointer-events: none;
  opacity: 0.9;
  transform: translate(-50%, -50%) rotate(-1deg);
  box-shadow: 0 22px 45px rgba(26, 39, 37, 0.22);
}

body.dragging-course {
  user-select: none;
}

.course-card header,
.selected-item header {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  align-items: flex-start;
}

.course-code {
  font-weight: 900;
  overflow-wrap: anywhere;
}

.subject-pill {
  max-width: 150px;
  border-radius: 999px;
  padding: 4px 8px;
  background: var(--panel-soft);
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 800;
  overflow-wrap: anywhere;
}

.course-meta,
.course-note {
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.35;
}

.course-card footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.course-card button,
.course-pick button,
.selected-item button,
.event button {
  min-height: 32px;
  padding: 0 10px;
  border-radius: 7px;
  font-size: 0.78rem;
}

.calendar-panel {
  overflow: hidden;
}

.calendar-head {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 14px;
  border-bottom: 1px solid var(--line);
  align-items: end;
}

#hintText {
  color: var(--muted);
  font-size: 0.88rem;
  max-width: 520px;
  text-align: right;
}

.calendar {
  display: grid;
  grid-template-columns: 64px repeat(5, minmax(128px, 1fr));
  overflow: auto;
  -webkit-overflow-scrolling: touch;
  background: var(--line);
  gap: 1px;
}

.cal-cell,
.cal-head,
.period-cell {
  min-height: 86px;
  background: #fff;
}

.cal-head,
.period-cell {
  display: grid;
  place-items: center;
  min-height: 48px;
  font-weight: 900;
}

/* Period column stays pinned while the week scrolls horizontally on narrow screens. */
.period-cell {
  position: sticky;
  left: 0;
  z-index: 2;
  color: var(--muted);
  box-shadow: 1px 0 0 var(--line);
}

.cal-head:first-child {
  position: sticky;
  left: 0;
  z-index: 3;
  box-shadow: 1px 0 0 var(--line);
}

.cal-cell {
  display: grid;
  align-content: start;
  gap: 5px;
  padding: 7px;
  transition: background 160ms ease, box-shadow 160ms ease;
}

.cal-cell.drop-target {
  background: #eaf4ef;
  box-shadow: inset 0 0 0 2px var(--tutor);
}

.cal-cell.blocked {
  background: #fbefef;
  box-shadow: inset 0 0 0 2px var(--danger);
}

.event {
  display: grid;
  gap: 4px;
  min-height: 52px;
  border-radius: 7px;
  padding: 7px;
  color: #fff;
  background: var(--gk);
  box-shadow: 0 8px 18px rgba(26, 39, 37, 0.16);
}

.event.tutor,
.event.lmm {
  background: var(--tutor);
}

.event.lok {
  background: var(--lok);
}

.event.extra {
  background: var(--extra);
}

.event.conflict {
  outline: 3px solid rgba(185, 64, 64, 0.45);
  background: var(--danger);
}

.event strong,
.event span {
  overflow-wrap: anywhere;
}

.event strong {
  font-size: 0.82rem;
}

.event span {
  font-size: 0.71rem;
  opacity: 0.92;
}

.event-tag {
  display: inline-block;
  margin-left: 4px;
  padding: 1px 5px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.26);
  font-size: 0.64rem;
  font-style: normal;
  font-weight: 800;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  opacity: 1;
}

.event button {
  justify-self: end;
  border-color: rgba(255, 255, 255, 0.3);
  background: rgba(255, 255, 255, 0.18);
  color: #fff;
}

.selection-panel {
  display: grid;
  grid-template-columns: 220px minmax(0, 1fr);
  gap: 16px;
  margin-top: 16px;
  padding: 14px;
}

.selected-courses {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 10px;
}

.selected-item {
  display: grid;
  gap: 7px;
  border: 1px solid var(--line);
  border-left: 5px solid var(--gk);
  border-radius: 8px;
  background: #fff;
  padding: 10px;
}

.selected-item.tutor {
  border-left-color: var(--tutor);
}

.selected-item.lok {
  border-left-color: var(--lok);
}

.selected-item.extra {
  border-left-color: var(--extra);
}

.empty-state {
  color: var(--muted);
  font-size: 0.92rem;
  padding: 8px 0;
}

.intro-overlay {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(16, 24, 22, 0.55);
  backdrop-filter: blur(2px);
}

.intro-overlay[hidden] {
  display: none;
}

.intro-card {
  width: min(560px, 100%);
  max-height: calc(100vh - 40px);
  overflow-y: auto;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  box-shadow: var(--shadow);
  padding: 26px 28px;
}

.intro-card h2 {
  margin: 4px 0 10px;
  font-size: 1.5rem;
}

.intro-lead {
  color: var(--muted);
  margin-bottom: 14px;
}

.intro-steps {
  list-style: none;
  counter-reset: step;
  margin: 0 0 18px;
  padding: 0;
  display: grid;
  gap: 14px;
}

.intro-steps li {
  counter-increment: step;
  display: grid;
  grid-template-columns: auto 1fr;
  column-gap: 12px;
  align-items: start;
}

.intro-steps li::before {
  content: counter(step);
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--tutor);
  color: #fff;
  font-weight: 800;
  font-size: 0.95rem;
}

.intro-steps strong {
  grid-column: 2;
  display: block;
  margin-bottom: 2px;
}

.intro-steps span {
  grid-column: 2;
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.4;
}

.intro-note {
  border-left: 3px solid var(--lok);
  background: var(--panel-soft);
  padding: 10px 12px;
  border-radius: 0 8px 8px 0;
  font-size: 0.92rem;
  margin-bottom: 18px;
}

.intro-card #introClose {
  width: 100%;
  min-height: 46px;
}

.intro-hint {
  margin-top: 12px;
  text-align: center;
  color: var(--muted);
  font-size: 0.82rem;
}

@media (max-width: 1040px) {
  .workspace {
    grid-template-columns: 1fr;
  }

  .course-browser {
    position: static;
    max-height: none;
  }

  .course-list {
    max-height: 420px;
  }
}

@media (max-width: 760px) {
  .app-shell {
    padding: 12px;
  }

  .topbar,
  .calendar-head,
  .status-strip,
  .selection-panel {
    grid-template-columns: 1fr;
    display: grid;
  }

  .topbar {
    gap: 12px;
  }

  .top-actions {
    justify-content: stretch;
  }

  .top-actions button {
    flex: 1;
  }

  .calendar-head {
    gap: 6px;
  }

  .setup-panel {
    grid-template-columns: 1fr;
  }

  #hintText {
    text-align: left;
    max-width: none;
  }

  .calendar {
    grid-template-columns: 42px repeat(5, minmax(112px, 1fr));
  }

  .cal-cell {
    min-height: 90px;
    padding: 6px;
  }

  .intro-card {
    padding: 20px 18px;
  }

  .intro-card h2 {
    font-size: 1.3rem;
  }
}

@media (max-width: 400px) {
  .app-shell {
    padding: 9px;
  }

  .calendar {
    grid-template-columns: 38px repeat(5, minmax(104px, 1fr));
  }

  .status-strip {
    grid-template-columns: repeat(2, 1fr);
  }

  .status-strip .build-status {
    grid-column: 1 / -1;
  }
}

@media print {
  @page {
    size: A4 landscape;
    margin: 7mm;
  }

  * {
    print-color-adjust: exact;
    -webkit-print-color-adjust: exact;
  }

  body {
    background: #fff;
    color: #111;
  }

  .top-actions,
  .course-browser,
  .setup-panel,
  .selection-panel,
  #hintText,
  .intro-overlay,
  .event button {
    display: none;
  }

  .app-shell {
    width: 100%;
    padding: 0;
  }

  .workspace {
    display: block;
    margin-top: 5px;
  }

  .topbar {
    display: block;
    padding: 0 0 5px;
    border: 0;
    background: #fff;
  }

  .topbar .eyebrow {
    font-size: 8px;
  }

  h1 {
    font-size: 18px;
    line-height: 1;
  }

  h2 {
    font-size: 12px;
    line-height: 1;
  }

  .status-strip {
    grid-template-columns: 72px 82px 1fr;
    gap: 8px;
    margin-top: 0;
    padding: 4px 0 6px;
    border: 0;
    background: #fff;
  }

  .status-strip strong {
    font-size: 16px;
  }

  .status-strip span,
  .build-status {
    font-size: 9px;
    line-height: 1.15;
  }

  .calendar-panel {
    border: 1px solid #cfd5ce;
    border-radius: 0;
    overflow: visible;
    background: #fff;
  }

  .calendar-head {
    display: block;
    padding: 4px 6px;
    border-bottom: 1px solid #cfd5ce;
  }

  .calendar-head .eyebrow {
    display: none;
  }

  .calendar {
    grid-template-columns: 34px repeat(5, 1fr);
    overflow: visible;
    gap: 1px;
    background: #cfd5ce;
  }

  .cal-head,
  .period-cell {
    min-height: 24px;
    font-size: 10px;
    line-height: 1;
  }

  .cal-cell {
    min-height: 45px;
    gap: 2px;
    padding: 3px;
  }

  .event {
    min-height: 0;
    gap: 1px;
    border-radius: 3px;
    padding: 3px 4px;
    box-shadow: none;
    break-inside: avoid;
  }

  .event strong {
    font-size: 8px;
    line-height: 1.05;
  }

  .event span {
    font-size: 7px;
    line-height: 1.05;
  }

  .topbar,
  .status-strip,
  .calendar-panel {
    box-shadow: none;
  }

  .calendar-panel,
  .calendar {
    page-break-inside: avoid;
    break-inside: avoid;
  }
}