/* Calm study surfaces: clear hierarchy, comfortable controls, immediate navigation. */
:root {
  --surface-border: #2c4047;
  --surface-raised: #192c32;
  --text-secondary: #b5c8ca;
  --press-ease: cubic-bezier(.23, 1, .32, 1);
}

body {
  -webkit-text-size-adjust: 100%;
}

button, summary, select {
  -webkit-tap-highlight-color: transparent;
}

summary:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

button:disabled {
  transform: none;
}

.topbar {
  border-bottom-color: var(--surface-border);
  padding-left: max(1.4rem, env(safe-area-inset-left));
  padding-right: max(1.4rem, env(safe-area-inset-right));
}

.brand strong {
  letter-spacing: .09em;
}

.brand strong #course-name {
  font-size: .75rem;
  letter-spacing: .06em;
}

.mode-switch {
  padding: 4px;
  border: 1px solid var(--surface-border);
  background: #101d24;
}

.mode-switch button {
  min-height: 40px;
  padding: .55rem .9rem;
  font-size: .875rem;
}

.topbar-actions button,
.more-menu > summary {
  min-height: 42px;
  font-size: .8125rem;
}

.more-menu > div {
  border-color: #3a5057;
  box-shadow: 0 12px 32px #0005;
}

.lesson-route {
  min-height: 58px;
  gap: .6rem;
  border-bottom-color: var(--surface-border);
}

.lesson-route button {
  min-height: 40px;
  padding: .5rem .75rem;
  font-size: .8125rem;
}

.lesson-route #route-label {
  min-width: 0;
  font-size: .8125rem;
  line-height: 1.5;
  color: var(--text-secondary);
}

.workspace,
.workspace.quiz-active,
.workspace.figures-open {
  height: calc(100dvh - var(--header-height, 80px) - var(--route-height, 58px));
  min-height: 480px;
  grid-template-columns: minmax(0, 1fr) minmax(350px, var(--lesson-width));
}

.stage-heading {
  padding: 1.2rem 1.4rem .65rem;
}

.stage-heading .eyebrow {
  font-size: .75rem;
  letter-spacing: .1em;
  margin-bottom: .35rem;
}

.stage-heading h2 {
  font-size: 1.1rem;
  line-height: 1.45;
  color: #d2e1df;
}

.stage-heading .tag {
  font-size: .75rem;
  border-color: var(--surface-border);
}

#stage,
.figures-open #stage {
  order: 2;
  min-height: 220px;
}

/* Tools are in normal flow so expanding them never covers the model. */
.viewer-tools,
.learning-active .viewer-tools,
.dissector-open .viewer-tools {
  position: relative;
  order: 3;
  inset: auto;
  margin: .25rem 1rem;
  align-self: flex-start;
  max-width: calc(100% - 2rem);
}

.viewer-tools > summary {
  display: flex;
  align-items: center;
  min-height: 42px;
  font-size: .8125rem;
  padding: .5rem .7rem;
  color: var(--text-secondary);
  background: #14242d;
}

.viewer-tools[open] {
  max-width: min(480px, calc(100% - 2rem));
  border-color: #354d55;
  box-shadow: none;
}

.viewer-tools .atlas-note {
  font-size: .8125rem;
  line-height: 1.55;
}

.camera-bar,
.dissector-open .camera-bar {
  order: 4;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: .5rem 1rem;
  padding: .35rem 1rem .5rem;
}

.camera-presets,
.camera-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: .2rem;
}

.camera-presets {
  padding: 3px;
  border: 1px solid var(--surface-border);
  border-radius: 10px;
  background: #111f27;
}

.camera-bar button,
.dissector-open .camera-bar button {
  min-height: 40px;
  padding: .45rem .6rem;
  font-size: .8125rem;
}

.camera-bar #reset-button {
  color: #98afb4;
}

.camera-bar #clear-selection {
  border-color: #4c7268;
  color: #d5eee4;
}

.camera-bar button:active:not(:disabled),
.lesson-route button:active:not(:disabled),
.dissector-toolbar button:active:not(:disabled) {
  background: #2a4547;
}

.viewer-footer {
  order: 5;
  font-size: .75rem;
  line-height: 1.5;
  padding: .15rem 1rem .8rem;
  color: #a0b8ba;
  text-align: center;
}

.view-status {
  order: 6;
  font-size: .8125rem;
}

.study-panel,
.figures-open > .study-panel {
  border-color: var(--surface-border);
  background: #152329;
  scrollbar-gutter: stable;
}

.lesson-progress,
.lesson-panel .lesson-advance .meta,
.lesson-source,
.lesson-selection-name {
  font-size: .8125rem;
  line-height: 1.5;
}

.lesson-cue .eyebrow,
.lesson-section-label {
  font-size: .75rem;
  letter-spacing: .09em;
}

.lesson-cue {
  border-left-width: 2px;
}

.restore-lesson-view {
  min-height: 44px;
  padding: .45rem .65rem;
  margin-top: .6rem;
  font-size: .8125rem;
  line-height: 1.5;
  text-align: left;
  color: #cce6dc;
  border-color: #3c5b54;
  background: transparent;
}

#lesson-essentials li {
  color: #d3dfdf;
  font-size: 1rem;
}

.lesson-details {
  border-top-color: var(--surface-border);
}

.lesson-details > summary {
  min-height: 44px;
  padding: .5rem 0;
  font-size: .875rem;
}

.lesson-details p,
.lesson-details li,
.lesson-details .structure-button {
  font-size: .9375rem;
}

.lesson-panel .lesson-advance {
  border-top-color: #3b514f;
  background: #152329;
  padding-top: .85rem;
  padding-bottom: .6rem;
}

.lesson-panel .lesson-advance > .primary {
  min-height: 46px;
  font-size: .9375rem;
}

.walk-navigation {
  align-items: center;
}

.walk-navigation button,
.lesson-advance #walk-check {
  min-height: 44px;
  font-size: .875rem;
}

.home-panel {
  padding-top: clamp(2rem, 4vh, 3.5rem);
}

.home-hero h1 {
  max-width: 22ch;
  font-size: clamp(2rem, 3.2vw, 2.75rem);
  line-height: 1.17;
  text-wrap: balance;
}

.home-hero p {
  color: var(--text-secondary);
  max-width: 55ch;
  line-height: 1.6;
}

.course-cards {
  gap: 1rem;
}

.course-card {
  padding: 1.5rem !important;
  border-color: #30484e !important;
  border-radius: 16px;
}

.course-card h2 {
  font-size: 1.55rem;
}

.course-subtitle {
  font-size: .9375rem;
  color: #bdcecf;
}

.course-open {
  min-height: 46px;
  font-size: .9375rem;
  border-radius: 9px;
  transition: transform 120ms var(--press-ease);
}

.course-open:active:not(:disabled):not(:focus-visible) {
  transform: scale(.98);
}

.course-card.pending {
  opacity: 1;
  border-color: #283c43 !important;
  border-radius: 12px;
}

.pending h2 {
  color: #afc0c5;
}

.pending .course-badge,
.course-pending,
.home-footer p {
  font-size: .8125rem;
}

.resume-card {
  border-color: #638f7d;
  background: #1b342e;
}

.resume-card .eyebrow {
  font-size: .75rem;
}

.resume-card h2 {
  font-size: 1.15rem;
}

.resume-card p {
  font-size: .875rem;
}

.resume-card button {
  min-height: 46px;
}

.dissector-panel {
  border-color: #3b5052;
}

.dissector-heading {
  padding: .8rem 1rem .35rem;
}

.dissector-heading > div:first-child {
  flex: 1;
  min-width: 0;
}

.dissector-heading-actions {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  gap: 6px;
}

#follow-dissector {
  padding: .4rem .55rem;
  font-size: .8125rem;
  line-height: 1.4;
  color: #b9d4cb;
  background: transparent;
  border-color: #3b5751;
}

#follow-dissector[aria-pressed="true"] {
  color: #d0eee1;
  background: #233d35;
  border-color: #466d5e;
}

.dissector-position {
  display: block;
  margin-top: 4px;
  font-size: .75rem;
  line-height: 1.5;
  color: #a2bcba;
}

.dissector-heading .eyebrow {
  font-size: .75rem;
  letter-spacing: .09em;
}

.dissector-heading h2 {
  font-size: .9375rem;
  line-height: 1.45;
}

.dissector-heading button {
  min-height: 40px;
  min-width: 40px;
}

.dissector-follow {
  flex-wrap: wrap;
  padding: .25rem 1rem;
  font-size: .8125rem;
  line-height: 1.5;
}

.dissector-follow button {
  min-height: 40px;
  font-size: .8125rem;
  padding: .4rem .65rem;
}

.dissector-toolbar {
  gap: .35rem;
  padding: .4rem 1rem .65rem;
}

.dissector-toolbar button,
.dissector-toolbar select {
  min-height: 44px;
  font-size: .875rem;
  padding: .4rem .6rem;
}

.dissector-text-page {
  font-size: calc(1rem * var(--reader-scale, 1));
  line-height: 1.7;
  padding-top: 1.3rem;
}

.source-page-label {
  font-size: .75rem;
}

.dissector-jump {
  font-size: .8125rem;
  min-height: 40px;
}

.dissector-foot {
  flex-wrap: wrap;
  align-items: center;
  padding: .7rem 1rem;
  font-size: .75rem;
  line-height: 1.5;
}

.dissector-foot a {
  padding: .2rem 0;
}

.dissector-open .guide {
  top: 0;
}

#compact-reader-switch {
  display: none;
}

@media (hover: hover) and (pointer: fine) {
  .camera-bar button:hover:not(:disabled),
  .lesson-route button:hover:not(:disabled) {
    background: #20383e;
    color: #e0ede7;
  }

  .course-open:hover:not(:disabled) {
    background: #b8ead9;
    color: #132d25;
    border-color: #b8ead9;
  }

  .lesson-details > summary:hover {
    color: #edf6ef;
  }
}

@media (min-width: 1200px) {
  .workspace.dissector-open {
    max-width: 1900px;
    grid-template-columns: minmax(320px, 30%) minmax(300px, 1fr) minmax(350px, 27%);
    grid-template-rows: minmax(0, 1fr);
    height: calc(100dvh - var(--header-height, 80px) - var(--route-height, 58px));
  }

  .dissector-open .dissector-panel {
    grid-column: 1;
    grid-row: 1;
    height: auto;
  }

  .dissector-open .viewer-panel {
    grid-column: 2;
    grid-row: 1;
  }

  .dissector-open .study-panel {
    grid-column: 3;
    grid-row: 1;
    min-height: 0;
    max-height: 100%;
  }
}

@media (min-width: 741px) and (max-width: 1199px) {
  .workspace.dissector-open {
    height: auto;
    min-height: 0;
    grid-template-columns: minmax(0, .95fr) minmax(0, 1.05fr);
    grid-template-rows: minmax(540px, calc(100dvh - var(--header-height, 80px) - var(--route-height, 58px))) auto;
  }

  .dissector-open .dissector-panel {
    grid-column: 1;
    grid-row: 1;
    height: auto;
    min-height: 0;
    border-bottom: 0;
  }

  .dissector-open .viewer-panel {
    grid-column: 2;
    grid-row: 1;
    min-height: 0;
  }

  .dissector-open .study-panel,
  .dissector-open .study-panel.lesson-panel {
    grid-column: 1 / -1;
    grid-row: 2;
    min-height: 0;
    max-height: none;
    overflow: visible;
    border-left: 0;
    border-top: 1px solid var(--surface-border);
  }

  .dissector-open #lesson-reading {
    width: 100%;
    max-width: 940px;
    margin: auto;
    padding: 1.6rem;
    overflow: visible;
  }

  .dissector-open #lesson-reading > p,
  .dissector-open #lesson-essentials,
  .dissector-open .lesson-cue {
    max-width: 70ch;
  }

  .dissector-open .lesson-advance {
    position: static;
    padding: 1rem 1.6rem;
  }

  .dissector-open .stage-heading {
    padding: 1rem;
  }

  .dissector-open .stage-heading h2 {
    font-size: 1rem;
  }

  .dissector-open .camera-bar {
    gap: .35rem;
    padding: .35rem .5rem;
  }

  .dissector-open .camera-bar button {
    min-height: 44px;
    padding: .45rem .55rem;
  }

  .dissector-text-page {
    padding-left: .85rem;
    padding-right: .85rem;
  }
}

@media (max-width: 740px) {
  .topbar {
    padding: .65rem max(.85rem, env(safe-area-inset-right)) .65rem max(.85rem, env(safe-area-inset-left));
  }

  .topbar > .brand {
    flex-basis: 55%;
  }

  .topbar .lab-picker select,
  .dissector-toolbar select,
  .side-control select,
  .quiz-filters select {
    font-size: 1rem;
  }

  .topbar .lab-picker select {
    max-width: 100%;
    min-height: 40px;
  }

  .topbar-actions button,
  .more-menu > summary,
  .mode-switch button {
    min-height: 44px;
  }

  .lesson-route {
    padding: .5rem .8rem;
    gap: .35rem;
  }

  .lesson-route button {
    min-height: 44px;
  }

  .lesson-route #route-label {
    font-size: .8125rem;
    padding: .25rem .2rem 0;
  }

  .workspace,
  .workspace.quiz-active,
  .workspace.figures-open,
  .workspace.dissector-open {
    height: auto;
    min-height: 0;
  }

  .workspace.dissector-open.source-reading .viewer-panel,
  .workspace.dissector-open.source-reading .study-panel,
  .workspace.dissector-open.source-anatomy .dissector-panel {
    display: none;
  }

  .workspace.dissector-open.source-reading .dissector-panel {
    display: flex;
    height: max(420px, calc(100dvh - var(--header-height, 130px) - var(--route-height, 130px)));
    min-height: 0;
    flex: 0 0 auto;
    border-right: 0;
    border-bottom: 0;
  }

  #compact-reader-switch {
    flex: 1 0 100%;
    gap: .3rem;
    padding: 4px;
    border: 1px solid var(--surface-border);
    background: #101d24;
    border-radius: 10px;
  }

  #compact-reader-switch:not([hidden]) {
    display: flex;
  }

  #compact-reader-switch button {
    flex: 1;
    min-height: 44px;
    border: 0;
    font-size: .875rem;
  }

  #compact-reader-switch button[aria-pressed="true"] {
    background: #2a4940;
    color: #e0fff1;
  }

  .dissector-panel {
    order: 0;
  }

  .dissector-open .guide {
    top: 0;
  }

  .viewer-tools,
  .learning-active .viewer-tools,
  .dissector-open .viewer-tools {
    margin: .2rem .75rem;
    max-width: calc(100% - 1.5rem);
  }

  .viewer-tools > summary {
    min-height: 44px;
  }

  .camera-bar,
  .dissector-open .camera-bar {
    gap: .3rem;
    padding: .3rem .55rem .5rem;
  }

  .camera-bar button,
  .dissector-open .camera-bar button {
    min-height: 44px;
    padding: .45rem .65rem;
  }

  .viewer-footer {
    font-size: .75rem;
    padding: .15rem .8rem .7rem;
  }

  .study-panel.lesson-panel,
  .dissector-open .study-panel.lesson-panel {
    overflow: visible;
  }

  .lesson-panel .lesson-advance {
    padding-bottom: max(1rem, env(safe-area-inset-bottom));
  }

  .dissector-foot {
    padding-bottom: max(.7rem, env(safe-area-inset-bottom));
  }

  .dissector-text-page {
    padding: 1rem .75rem 1.5rem;
  }

  .dissector-jump {
    min-height: 44px;
  }

  .home-panel {
    padding: 1.8rem 1rem max(1.5rem, env(safe-area-inset-bottom));
  }

  .home-hero h1 {
    font-size: 2rem;
  }

  .course-card {
    padding: 1.2rem !important;
  }

  .course-cards {
    gap: .8rem;
  }

  .course-subtitle {
    min-height: 0;
  }

  .course-card.pending {
    padding: 1rem !important;
  }
}

@media (max-width: 520px) {
  .course-cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .course-card {
    grid-column: 1 / -1;
  }

  .course-card.pending {
    grid-column: span 1;
  }

  .course-card-top {
    margin-bottom: .65rem;
  }

  .course-subtitle {
    margin-bottom: 1rem;
  }

  .resume-card {
    gap: .85rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .course-open {
    transition: none;
  }

  .course-open:active:not(:disabled):not(:focus-visible) {
    transform: none;
  }
}

/* Keep expanded layer controls reachable on short laptop displays. */
@media (min-width: 741px) {
  .viewer-panel { overflow-x: hidden; overflow-y: auto; }
  .viewer-tools[open] { max-height: 180px; overflow-y: auto; flex-shrink: 0; }
}