:root {
  --bg: #fbfbfc;
  --text: #111;
  --muted: rgba(0, 0, 0, 0.65);
  --border: rgba(0, 0, 0, 0.45);
  --border-strong: rgba(0, 0, 0, 0.58);
  --card: #ffffff;

  --brand: #9e1b32;
  --brand-soft: rgba(158, 27, 50, 0.12);

  --radius-lg: 22px;
  --radius-md: 18px;
  --radius-sm: 14px;

  --shadow-sm: 0 10px 24px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 18px 44px rgba(0, 0, 0, 0.08);
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
}

a {
  color: inherit;
}

code {
  background: rgba(0, 0, 0, 0.04);
  padding: 2px 6px;
  border-radius: 10px;
}

/* Layout helpers for centering content while sidebar stays fixed */
.layoutShell {
  display: flex;
  min-height: 100vh;
}

.layoutSidebar {
  flex: 0 0 auto;
}

.layoutMain {
  flex: 1;
  display: flex;
  justify-content: center;
}

.layoutMainInner {
  width: 100%;
  max-width: 1200px;
  padding: 18px;
}

/* Home */

.home {
  max-width: 1200px;
  margin: 0 auto;
  padding: 30px 18px;
}

.hero {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 2.25rem;
  align-items: stretch;
  margin-bottom: 2.5rem;
}

.hero-content {
  background: linear-gradient(
    135deg,
    rgba(158, 27, 50, 0.08) 0%,
    rgba(158, 27, 50, 0.02) 45%,
    rgba(0, 0, 0, 0) 100%
  );
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-md);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  padding: 0.4rem 0.75rem;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--brand);
  background: var(--brand-soft);
  margin-bottom: 1rem;
}

.hero-title {
  font-size: 3.35rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  margin-bottom: 0.85rem;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: #444;
  line-height: 1.65;
  max-width: 50rem;
  margin-bottom: 1.75rem;
}

.hero-actions {
  display: flex;
  gap: 0.85rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  padding: 0.85rem 1.1rem;
  border-radius: 12px;
  font-weight: 700;
  background: var(--brand);
  color: white;
  border: 1px solid rgba(0, 0, 0, 0.06);
  box-shadow: 0 12px 26px rgba(158, 27, 50, 0.25);
  transition: transform 0.2s ease, box-shadow 0.2s ease, filter 0.2s ease;
}

.btn-primary:hover {
  transform: translateY(-2px);
  filter: brightness(0.98);
  box-shadow: 0 16px 34px rgba(158, 27, 50, 0.3);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  padding: 0.85rem 1.1rem;
  border-radius: 12px;
  font-weight: 700;
  background: white;
  color: #222;
  border: 1px solid rgba(0, 0, 0, 0.12);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn-secondary:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.1);
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.stat {
  background: var(--card);
  border-radius: 16px;
  padding: 1rem 1.1rem;
  border: 1px solid rgba(0, 0, 0, 0.06);
  box-shadow: 0 12px 26px rgba(0, 0, 0, 0.05);
}

.stat-value {
  font-weight: 850;
  font-size: 1.05rem;
  color: #111;
  margin-bottom: 0.25rem;
}

.stat-label {
  font-size: 0.92rem;
  color: #555;
  line-height: 1.35;
}

.hero-panel {
  display: flex;
}

.panel-card {
  width: 100%;
  background: var(--card);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(0, 0, 0, 0.06);
  box-shadow: var(--shadow-md);
  padding: 2rem;
  position: relative;
  overflow: hidden;
}

.panel-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  height: 6px;
  width: 100%;
  background: linear-gradient(90deg, #9e1b32 0%, #7d1427 60%, #2b0b12 100%);
}

.panel-title {
  font-weight: 850;
  font-size: 1.1rem;
  color: #111;
  margin-bottom: 1rem;
}

.panel-list {
  margin: 0;
  padding-left: 1.15rem;
  color: #333;
}

.panel-list li {
  margin-bottom: 0.6rem;
  line-height: 1.35;
}

.panel-foot {
  margin-top: 1.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid rgba(0, 0, 0, 0.08);
  color: #555;
  line-height: 1.5;
}

.features {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.5rem;
}

.feature {
  background: var(--card);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  border: 1px solid rgba(0, 0, 0, 0.06);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.06);
  transition: transform 0.22s ease, box-shadow 0.22s ease;
}

.feature:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 46px rgba(0, 0, 0, 0.1);
}

.feature-top {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  margin-bottom: 0.85rem;
}

.feature-icon {
  width: 34px;
  height: 34px;
  border-radius: 12px;
  background: rgba(158, 27, 50, 0.14);
  border: 1px solid rgba(158, 27, 50, 0.2);
}

.feature h3 {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 850;
  color: var(--brand);
}

.feature p {
  margin: 0;
  color: #444;
  line-height: 1.6;
}

/* Simulation and editor shared shell */

.simShell {
  max-width: 980px;
  margin: 0 auto;
  padding: 18px;
}

.simHeaderRow {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.simHeaderText {
  flex: 1;
}

.simBadge {
  display: inline-block;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.06);
  font-weight: 600;
  font-size: 12px;
}

.simTitle {
  font-size: 26px;
  font-weight: 800;
  margin-top: 10px;
}

.simSubtitle {
  opacity: 0.7;
  margin-top: 6px;
}

.simGridSingle {
  display: grid;
  grid-template-columns: 1fr;
}

/* Shared card and typographic blocks */

.card {
  background: var(--card);
  border-radius: var(--radius-md);
  padding: 18px;
  box-shadow: var(--shadow-sm);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

.sectionTitle {
  font-weight: 900;
  margin-bottom: 10px;
}

.narrLine {
  padding: 8px 0;
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.divider {
  height: 1px;
  background: rgba(0, 0, 0, 0.08);
  margin: 16px 0;
}

/* Buttons */

.primaryBtn {
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  background: white;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.primaryBtn:hover {
  background: rgba(0, 0, 0, 0.04);
  transform: translateY(-1px);
}

.primaryBtn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.secondaryBtn {
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  background: white;
  font-weight: 600;
  font-size: 13px;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.secondaryBtn:hover {
  background: rgba(0, 0, 0, 0.04);
  transform: translateY(-1px);
}

.secondaryBtn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* Editor and form controls */

.editorHeader {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.saveMessage {
  padding: 12px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  margin-top: 10px;
}

.saveMessage.success {
  background: rgba(34, 197, 94, 0.1);
  color: rgb(21, 128, 61);
  border: 1px solid rgba(34, 197, 94, 0.3);
}

.saveMessage.error {
  background: rgba(239, 68, 68, 0.1);
  color: rgb(185, 28, 28);
  border: 1px solid rgba(239, 68, 68, 0.3);
}

.scenarioTitleEditor {
  margin-bottom: 8px;
}

.nodesHeader {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.nodeHeaderActions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.editorLabel {
  display: block;
  font-weight: 700;
  margin-bottom: 6px;
  font-size: 14px;
}

.editorInput,
.editorTextarea {
  width: 100%;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-strong);
  font-family: inherit;
  background: white;
}

.editorInput:focus,
.editorTextarea:focus {
  outline: none;
  box-shadow: 0 0 0 4px rgba(0, 0, 0, 0.1);
  border-color: rgba(0, 0, 0, 0.22);
}

.editorTextarea {
  resize: vertical;
  min-height: 80px;
}

.scenarioBar {
  position: relative;
}

.scenarioInlineSelect {
  height: 36px;
  padding: 0 14px;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  background: rgba(0, 0, 0, 0.03);
  font-size: 13px;
  font-weight: 800;
  outline: none;
  cursor: pointer;
}

.scenarioInlineSelect:focus {
  box-shadow: 0 0 0 4px rgba(0, 0, 0, 0.12);
  border-color: rgba(0, 0, 0, 0.22);
}

.adminUserList {
  display: grid;
  gap: 12px;
}

.adminShell {
  display: grid;
  gap: 18px;
}

.adminSectionCard {
  padding: 22px 24px;
}

.adminInfoLine {
  border-bottom: 0;
  padding-bottom: 0;
 }

.adminModalLabel {
  margin-top: 14px;
}

.adminConfirmText {
  padding-top: 4px;
  padding-bottom: 14px;
  line-height: 1.5;
}

.adminUserItem {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 18px 20px;
  border: 1px solid rgba(0, 0, 0, 0.08);
  border-radius: var(--radius-sm);
  background: rgba(0, 0, 0, 0.02);
}

.adminUserActions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.adminRoleChip {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 84px;
  padding: 7px 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 800;
  border: 1px solid transparent;
}

.adminRoleChipAdmin {
  background: rgba(158, 27, 50, 0.12);
  color: #7d1427;
  border-color: rgba(158, 27, 50, 0.22);
}

.adminRoleChipTeacher {
  background: rgba(0, 0, 0, 0.08);
  color: #111;
  border-color: rgba(0, 0, 0, 0.12);
}

.adminRoleChipStudent {
  background: rgba(59, 130, 246, 0.1);
  color: #1d4ed8;
  border-color: rgba(59, 130, 246, 0.18);
}

.demoCard {
  padding: 24px;
}

.demoMeta {
  display: grid;
  gap: 10px;
  margin-top: 4px;
  margin-bottom: 18px;
}

.demoMetaRow {
  padding: 0 0 10px;
  font-size: 18px;
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.demoLoginRow {
  align-items: center;
}

/* Simulation controls */

.prompt {
  font-weight: 700;
  margin-bottom: 12px;
}

.options {
  display: grid;
  gap: 10px;
}

.optionCard {
  text-align: left;
  border-radius: 16px;
  padding: 12px;
  border: 1px solid rgba(0, 0, 0, 0.1);
  cursor: pointer;
  background: rgba(0, 0, 0, 0.02);
  color: var(--text);
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.optionCard:hover {
  background: rgba(0, 0, 0, 0.04);
  transform: translateY(-1px);
}

.optionCard.selected {
  background: rgba(0, 0, 0, 0.06);
  border-color: rgba(0, 0, 0, 0.3);
  box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.18);
}

.optionCard:focus-visible {
  outline: 2px solid rgba(0, 0, 0, 0.28);
  outline-offset: 2px;
}

.optionKey {
  font-weight: 800;
  margin-bottom: 4px;
}

.optionText {
  opacity: 0.92;
}

.reasoning {
  margin-top: 14px;
}

.reasoningLabel {
  font-weight: 800;
  margin-bottom: 8px;
}

textarea {
  width: 100%;
  border-radius: var(--radius-sm);
  padding: 12px;
  border: 1px solid var(--border-strong);
  resize: vertical;
  background: white;
  font-family: inherit;
}

textarea:focus {
  outline: none;
  box-shadow: 0 0 0 4px rgba(0, 0, 0, 0.1);
  border-color: rgba(0, 0, 0, 0.22);
}

.actions {
  display: flex;
  gap: 10px;
  margin-top: 12px;
  flex-wrap: wrap;
}

.softFeedback {
  margin-top: 14px;
  border-radius: 16px;
  padding: 12px;
  background: rgba(0, 0, 0, 0.03);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

.softTitle {
  font-weight: 900;
  margin-bottom: 6px;
}

.softText,
.summaryText {
  color: var(--text);
}

.summaryBlock {
  margin-top: 14px;
}

.summaryLabel {
  font-weight: 900;
  margin-bottom: 6px;
}

.noteLine {
  padding: 8px 0;
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.compareCard {
  margin-top: 14px;
  border-radius: 16px;
  padding: 14px;
  background: rgba(0, 0, 0, 0.02);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

.compareTitle {
  font-weight: 900;
  margin-bottom: 10px;
}

.compareGrid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.compareCol {
  border-radius: var(--radius-sm);
  padding: 12px;
  background: white;
  border: 1px solid rgba(0, 0, 0, 0.06);
}

.compareLabel {
  font-weight: 900;
  margin-bottom: 6px;
}

.compareText {
  opacity: 0.9;
}

.compareSmall {
  margin-top: 8px;
  opacity: 0.7;
  font-size: 13px;
}

.compareFooter {
  margin-top: 12px;
  border-radius: var(--radius-sm);
  padding: 12px;
  background: white;
  border: 1px solid rgba(0, 0, 0, 0.06);
}

/* Node editor */

.nodeCard {
  border-radius: 16px;
  padding: 12px;
  margin-bottom: 12px;
  background: rgba(0, 0, 0, 0.02);
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-left: 3px solid hsl(calc(220 - var(--depth, 0) * 15), 70%, 55%);
  transition: all 0.2s;
}

.nodeCard:hover {
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.nodeCard.selected {
  background: rgba(0, 0, 0, 0.05);
  border-color: rgba(0, 0, 0, 0.2);
  box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.12);
}

.nodeHeader {
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  padding: 4px 0;
}

.nodeHeaderLeft {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
}

.expandBtn {
  border: none;
  border-radius: 100%;
  cursor: pointer;
  font-size: 16px;
  padding: 4px 8px;
  padding-top: 0px;
  color: rgba(0, 0, 0, 0.7);
  transition: transform 0.2s;
}

.expandBtn.expanded {
  transform: rotate(90deg);
}

.nodeTitle {
  font-weight: 800;
  font-size: 14px;
}

.nodeBadge {
  display: inline-block;
  padding: 4px 8px;
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.08);
  font-weight: 600;
  font-size: 11px;
  text-transform: uppercase;
}

.nodeBody {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid rgba(0, 0, 0, 0.08);
}

.editorField {
  margin-bottom: 14px;
}

.choiceList {
  margin-top: 8px;
}

.choiceCard {
  border-radius: var(--radius-sm);
  padding: 10px;
  margin-bottom: 8px;
  background: white;
  border: 1px solid rgba(0, 0, 0, 0.1);
}

.choiceHeader {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  gap: 10px;
}

.choiceActions {
  display: flex;
  gap: 6px;
  flex-shrink: 0;
  flex-wrap: wrap;
}

.choiceLabel {
  font-weight: 700;
  font-size: 13px;
}

.checkboxField {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
}

.checkboxField input[type="checkbox"] {
  width: auto;
}

.nestedNodes {
  margin-left: 16px;
  margin-top: 8px;
  padding-left: 12px;
  border-left: 2px solid rgba(0, 0, 0, 0.08);
}

.fieldHeader {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
}

.addBtn,
.deleteBtn,
.duplicateBtn,
.addNodeBtn,
.deleteNodeBtn {
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid rgba(0, 0, 0, 0.12);
  background: white;
  font-weight: 600;
  font-size: 12px;
  cursor: pointer;
  transition: all 0.2s;
}

.addBtn,
.addNodeBtn {
    background: rgb(238, 246, 241);
    color: rgb(21, 128, 61);
    border-color: rgba(34, 197, 94, 0.3);
}

    .addBtn:hover,
    .addNodeBtn:hover {
        color: rgb(17, 102, 49);
        background: rgba(34, 197, 94, 0.1);
    }

.duplicateBtn {
  background: rgba(59, 130, 246, 0.1);
  color: rgb(30, 64, 175);
  border-color: rgba(59, 130, 246, 0.3);
}

.duplicateBtn:hover {
  background: rgba(59, 130, 246, 0.2);
}

.deleteBtn,
.deleteNodeBtn {
  background: rgba(239, 68, 68, 0.1);
  color: rgb(185, 28, 28);
  border-color: rgba(239, 68, 68, 0.3);
}

.deleteBtn:hover,
.deleteNodeBtn:hover {
  background: rgba(239, 68, 68, 0.2);
}

.nodeActions {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid rgba(0, 0, 0, 0.06);
}

.warningMessage,
.infoMessage {
  padding: 10px 12px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 13px;
  margin-bottom: 12px;
}

.warningMessage {
  background: rgba(245, 158, 11, 0.1);
  color: rgb(161, 98, 7);
  border: 1px solid rgba(245, 158, 11, 0.3);
}

.infoMessage {
  background: rgba(59, 130, 246, 0.1);
  color: rgb(30, 64, 175);
  border: 1px solid rgba(59, 130, 246, 0.3);
}

/* Responsive */

@media (max-width: 980px) {
  .hero {
    grid-template-columns: 1fr;
  }

  .features {
    grid-template-columns: 1fr;
  }

  .hero-stats {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 900px) {
  .compareGrid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 520px) {
  .home {
    padding: 18px;
  }

  .hero-content {
    padding: 1.6rem;
  }

  .hero-title {
    font-size: 2.5rem;
  }
}

.hero-title:focus,
.hero-title:focus-visible {
  outline: none;
  box-shadow: none;
}


.classMgmtTop {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.classMgmtCreate,
.classMgmtSelect {
  display: grid;
  gap: 10px;
  align-content: start;
}

.classMgmtCardGap {
  margin-top: 16px;
}

.classMgmtAddRow {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: end;
}

.classMgmtRosterHeader {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 10px;
}

.classMgmtCount {
  opacity: 0.7;
  font-weight: 700;
  font-size: 13px;
}

.classMgmtRoster {
  display: grid;
  gap: 10px;
}

.classMgmtStudent {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 10px 12px;
  border-radius: 14px;
  background: rgba(0, 0, 0, 0.02);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

.classMgmtStudentEmail {
  font-weight: 800;
}

.assignmentCreateGrid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr 1fr auto;
  gap: 12px;
  align-items: end;
}

.assignmentTopRow {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

.assignmentCreateAction {
  min-width: 160px;
}

.classMgmtModalBackdrop {
  position: fixed;
  inset: 0;
  z-index: 1200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(15, 23, 42, 0.62);
  backdrop-filter: blur(2px);
}

.classMgmtModalCard {
  width: min(920px, calc(100vw - 48px));
  border: 1px solid rgba(15, 23, 42, 0.25);
  border-radius: 18px;
  padding: 20px;
  background: #ffffff;
  box-shadow: 0 26px 70px rgba(15, 23, 42, 0.35);
}

.classMgmtModalCardNarrow {
  width: min(640px, calc(100vw - 48px));
}

.classMgmtModalTop {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

.assignmentModalForm {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.assignmentModalFormSingle {
  grid-template-columns: 1fr;
  margin-top: 10px;
}

.assignmentModalActions {
  display: flex;
  justify-content: flex-end;
  margin-top: 14px;
}

.assignmentList {
  display: grid;
  gap: 10px;
}

.assignmentItem {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 10px 12px;
  background: rgba(0, 0, 0, 0.02);
}

.assignmentItem.selected {
  border-color: var(--brand);
  box-shadow: 0 0 0 2px var(--brand-soft);
}

.assignmentInfo {
  flex: 1;
}

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

.assignmentDueModalActions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.assignmentTitle {
  font-weight: 800;
}

.assignmentMeta {
  color: var(--muted);
  font-size: 13px;
}

.gradingShell {
  max-width: 1360px;
}

.gradingMetaGrid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
}

.gradingMetaItem {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 10px 12px;
  background: rgba(0, 0, 0, 0.02);
}

.gradingMetaLabel {
  font-size: 12px;
  font-weight: 700;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: 4px;
}

.gradingMetaValue {
  font-weight: 800;
}

.gradeList {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(420px, 1fr));
  gap: 12px;
}

.gradesSingleColumn {
  grid-template-columns: 1fr;
}

.gradeCard {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px;
  background: rgba(0, 0, 0, 0.02);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.04);
}

.gradeStudentRow {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.gradeItemHeaderLine {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}

.gradeStatus {
  font-size: 12px;
  font-weight: 700;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 4px 10px;
}

.gradeStatus.done {
  color: #14532d;
  border-color: #14532d;
  background: #eaf7ef;
}

.gradeStatus.pending {
  color: #7c2d12;
  border-color: #7c2d12;
  background: #fff4db;
}

.gradeInputRow {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 12px;
  margin-bottom: 10px;
}

.submissionViewer {
  min-height: 70vh;
  width: 100%;
}

.submissionFocusCard {
  border: 2px solid var(--brand);
  border-radius: 20px;
  padding: 18px;
  background: linear-gradient(180deg, rgba(158, 27, 50, 0.06) 0%, var(--card) 36%);
  min-height: 80vh;
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.08);
}

.submissionViewerFull {
  min-height: 68vh;
}

.simShellWide {
  max-width: none;
}

.submissionModePage {
  min-height: calc(100vh - 70px);
  padding: 14px;
  border-radius: 20px;
  border: 2px solid var(--brand);
  background: linear-gradient(180deg, rgba(158, 27, 50, 0.08) 0%, var(--card) 30%);
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.08);
}

.submissionModeTop {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 12px;
}

.submissionModeBanner {
  display: inline-flex;
  align-items: center;
  margin-bottom: 12px;
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--brand-soft);
  color: var(--brand);
  border: 1px solid rgba(158, 27, 50, 0.35);
  font-weight: 800;
  letter-spacing: 0.01em;
}

.submissionFocusTitle {
  font-size: 1.35rem;
  font-weight: 900;
}

html[data-theme="dark"] .submissionFocusCard {
  background: linear-gradient(180deg, rgba(212, 58, 86, 0.22) 0%, var(--card) 34%);
  border-color: #fda4b4;
}

html[data-theme="dark"] .submissionModePage {
  background: linear-gradient(180deg, rgba(212, 58, 86, 0.26) 0%, var(--card) 30%);
  border-color: #fda4b4;
}

.actionChips {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 6px;
}

.actionChip {
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  background: white;
  font-weight: 800;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.actionChip:hover {
  background: rgba(0, 0, 0, 0.04);
  transform: translateY(-1px);
}

.actionChip.selected {
  background: var(--brand-soft);
  color: var(--brand);
  border-color: rgba(158, 27, 50, 0.25);
}

.createArea {
  margin-top: 16px;
}

.createRow {
  display: flex;
  gap: 10px;
  align-items: center;
  flex-wrap: wrap;
}

.createRow .editorInput {
  flex: 1;
  min-width: 260px;
}

.createHint {
  margin-top: 10px;
  color: rgba(0, 0, 0, 0.6);
  font-size: 13px;
  font-weight: 600;
}

.editArea {
  margin-top: 16px;
}

.editTopRow {
  display: flex;
  gap: 12px;
  align-items: flex-end;
  justify-content: space-between;
  flex-wrap: wrap;
}

.editSelect {
  flex: 1;
  min-width: 260px;
}

.kebabWrap {
  position: relative;
  display: flex;
  align-items: center;
}

.kebabBtn {
  height: 40px;
  width: 44px;
  border-radius: 14px;
  border: 1px solid var(--border-strong);
  background: white;
  font-weight: 900;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.kebabBtn:hover {
  background: rgba(0, 0, 0, 0.04);
  transform: translateY(-1px);
}

.kebabBtn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.kebabMenu {
  position: absolute;
  top: 46px;
  right: 0;
  width: 180px;
  background: white;
  border: 1px solid rgba(0, 0, 0, 0.12);
  border-radius: 14px;
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.12);
  padding: 6px;
  z-index: 50;
}

.kebabMenuItem {
  width: 100%;
  text-align: left;
  border: 0;
  background: transparent;
  padding: 10px 10px;
  border-radius: 12px;
  font-weight: 800;
  cursor: pointer;
}

.kebabMenuItem:hover {
  background: rgba(0, 0, 0, 0.05);
}

.kebabMenuItem.danger {
  color: rgb(185, 28, 28);
}


@media (max-width: 900px) {
  .classMgmtTop {
    grid-template-columns: 1fr;
  }

  .classMgmtAddRow {
    grid-template-columns: 1fr;
  }

  .assignmentCreateGrid,
  .gradeInputRow {
    grid-template-columns: 1fr;
  }

  .assignmentModalForm {
    grid-template-columns: 1fr;
  }

  .classMgmtModalBackdrop {
    align-items: flex-end;
    padding: 12px;
  }

  .classMgmtModalCard {
    border-radius: 16px 16px 0 0;
    max-height: 90vh;
    overflow-y: auto;
  }

  .gradingMetaGrid {
    grid-template-columns: 1fr;
  }
}


.scenarioAccessTop {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.scenarioAccessHint {
  color: rgba(0, 0, 0, 0.65);
  font-weight: 600;
  font-size: 13px;
  line-height: 1.4;
}

/* Settings */

.settingsRow {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
}

.settingsLabel {
  font-weight: 800;
}

.settingsSubLabel {
  color: var(--muted);
  margin-top: 4px;
}

.overlayToast {
  position: fixed;
  top: 16px;
  left: 50%;
  transform: translate(-50%, -20px);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: max-content;
  max-width: calc(100vw - 24px);
  padding: 10px 16px;
  border-radius: 999px;
  margin: 0;
  z-index: 1200;
  pointer-events: none;
  box-shadow: var(--shadow-md);
  animation: overlayToastDrop 3s ease-in-out forwards;
}

@keyframes overlayToastDrop {
  0% {
    opacity: 0;
    transform: translate(-50%, -20px);
  }
  12% {
    opacity: 1;
    transform: translate(-50%, 0);
  }
  82% {
    opacity: 1;
    transform: translate(-50%, 0);
  }
  100% {
    opacity: 0;
    transform: translate(-50%, -20px);
  }
}

/* Dark mode */

html[data-theme="dark"] {
  --bg: #111318;
  --text: #ecf0f6;
  --muted: rgba(236, 240, 246, 0.68);
  --border: rgba(236, 240, 246, 0.36);
  --border-strong: rgba(236, 240, 246, 0.5);
  --card: #1a1f27;
  --brand: #d43a56;
  --brand-soft: rgba(212, 58, 86, 0.24);
  --shadow-sm: 0 12px 26px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 20px 48px rgba(0, 0, 0, 0.42);
}

html[data-theme="dark"] body {
  background: var(--bg);
  color: var(--text);
}

html[data-theme="dark"] code {
  background: rgba(255, 255, 255, 0.12);
}

html[data-theme="dark"] .hero-content,
html[data-theme="dark"] .panel-card,
html[data-theme="dark"] .feature,
html[data-theme="dark"] .card,
html[data-theme="dark"] .compareCol,
html[data-theme="dark"] .compareFooter,
html[data-theme="dark"] .choiceCard,
html[data-theme="dark"] .kebabMenu {
  background: var(--card);
  border-color: var(--border);
}

html[data-theme="dark"] .hero-subtitle,
html[data-theme="dark"] .feature p,
html[data-theme="dark"] .panel-list,
html[data-theme="dark"] .panel-foot,
html[data-theme="dark"] .stat-label,
html[data-theme="dark"] .createHint,
html[data-theme="dark"] .scenarioAccessHint {
  color: var(--muted);
}

html[data-theme="dark"] .card,
html[data-theme="dark"] .sectionTitle,
html[data-theme="dark"] .simTitle,
html[data-theme="dark"] .simSubtitle,
html[data-theme="dark"] .narrLine,
html[data-theme="dark"] .prompt,
html[data-theme="dark"] .optionKey,
html[data-theme="dark"] .optionText,
html[data-theme="dark"] .reasoningLabel,
html[data-theme="dark"] .softTitle,
html[data-theme="dark"] .softText,
html[data-theme="dark"] .summaryLabel,
html[data-theme="dark"] .summaryText,
html[data-theme="dark"] .compareTitle,
html[data-theme="dark"] .compareLabel,
html[data-theme="dark"] .compareText,
html[data-theme="dark"] .nodeTitle,
html[data-theme="dark"] .choiceLabel,
html[data-theme="dark"] .editorLabel,
html[data-theme="dark"] .settingsLabel,
html[data-theme="dark"] .classMgmtStudentEmail {
  color: var(--text);
}

html[data-theme="dark"] .settingsSubLabel,
html[data-theme="dark"] .compareSmall,
html[data-theme="dark"] .simSubtitle,
html[data-theme="dark"] .narrLine {
  color: var(--muted);
}

html[data-theme="dark"] .panel-title,
html[data-theme="dark"] .stat-value,
html[data-theme="dark"] .feature h3 {
  color: var(--brand);
}

html[data-theme="dark"] .hero-badge {
  color: #ffd7df;
  background: rgba(212, 58, 86, 0.22);
  border: 1px solid rgba(212, 58, 86, 0.35);
}

html[data-theme="dark"] .panel-card::before {
  background: linear-gradient(90deg, #d43a56 0%, #b72643 58%, #7f172c 100%);
}

html[data-theme="dark"] .btn-primary {
  background: linear-gradient(135deg, #c92f4b 0%, #b72643 100%);
  border-color: rgba(212, 58, 86, 0.45);
  box-shadow: 0 12px 26px rgba(212, 58, 86, 0.32);
}

html[data-theme="dark"] .btn-primary:hover {
  box-shadow: 0 16px 34px rgba(212, 58, 86, 0.4);
}

html[data-theme="dark"] .actionChip.selected {
  background: rgba(212, 58, 86, 0.24);
  color: #ffd7df;
  border-color: rgba(212, 58, 86, 0.45);
}

html[data-theme="dark"] .scenarioAccessText,
html[data-theme="dark"] .simBadge {
  color: var(--text);
}

html[data-theme="dark"] .btn-secondary,
html[data-theme="dark"] .primaryBtn,
html[data-theme="dark"] .secondaryBtn,
html[data-theme="dark"] .actionChip,
html[data-theme="dark"] .kebabBtn {
  background: #202734;
  color: var(--text);
  border-color: var(--border-strong);
}

html[data-theme="dark"] .primaryBtn:hover,
html[data-theme="dark"] .secondaryBtn:hover,
html[data-theme="dark"] .actionChip:hover,
html[data-theme="dark"] .kebabBtn:hover,
html[data-theme="dark"] .btn-secondary:hover {
  background: #273041;
}

html[data-theme="dark"] .editorInput,
html[data-theme="dark"] .editorTextarea,
html[data-theme="dark"] textarea,
html[data-theme="dark"] .scenarioInlineSelect {
  background: #202734;
  color: var(--text);
  border-color: var(--border-strong);
}

html[data-theme="dark"] .editorInput::placeholder,
html[data-theme="dark"] .editorTextarea::placeholder,
html[data-theme="dark"] textarea::placeholder {
  color: rgba(236, 240, 246, 0.62);
}

html[data-theme="dark"] .editorInput:focus,
html[data-theme="dark"] .editorTextarea:focus,
html[data-theme="dark"] textarea:focus,
html[data-theme="dark"] .scenarioInlineSelect:focus {
  box-shadow: 0 0 0 4px rgba(236, 240, 246, 0.12);
  border-color: rgba(236, 240, 246, 0.32);
}

html[data-theme="dark"] .divider,
html[data-theme="dark"] .narrLine,
html[data-theme="dark"] .noteLine,
html[data-theme="dark"] .nodeBody {
  border-color: var(--border);
}

html[data-theme="dark"] .softFeedback,
html[data-theme="dark"] .compareCard,
html[data-theme="dark"] .nodeCard,
html[data-theme="dark"] .optionCard,
html[data-theme="dark"] .classMgmtStudent {
  background: rgba(236, 240, 246, 0.05);
  border-color: var(--border);
}

html[data-theme="dark"] .optionCard,
html[data-theme="dark"] .optionCard * {
  color: var(--text);
}

html[data-theme="dark"] .optionCard:hover {
  background: rgba(236, 240, 246, 0.08);
}

html[data-theme="dark"] .optionCard.selected,
html[data-theme="dark"] .nodeCard.selected {
  background: rgba(236, 240, 246, 0.1);
  border-color: rgba(236, 240, 246, 0.3);
}

.scenarioAccessGrid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.scenarioAccessItem {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 14px;
  border: 1px solid rgba(0, 0, 0, 0.08);
  background: rgba(0, 0, 0, 0.02);
}

.scenarioAccessItem input[type="checkbox"] {
  width: auto;
}

.scenarioAccessText {
  font-weight: 800;
  font-size: 13px;
  opacity: 0.9;
}

/* WCAG 2.2 AA contrast overrides */

.hero-content,
.panel-card,
.feature,
.card,
.stat,
.compareCol,
.compareFooter,
.softFeedback,
.compareCard,
.nodeCard,
.choiceCard,
.classMgmtStudent,
.scenarioAccessItem,
.kebabMenu,
.btn-secondary,
.primaryBtn,
.secondaryBtn,
.actionChip,
.kebabBtn,
.editorInput,
.editorTextarea,
textarea,
.scenarioInlineSelect,
.optionCard,
.addBtn,
.deleteBtn,
.duplicateBtn,
.addNodeBtn,
.deleteNodeBtn,
.saveMessage,
.warningMessage,
.infoMessage {
  border-color: var(--border);
}

.narrLine,
.noteLine,
.nodeBody,
.nodeActions,
.panel-foot {
  border-color: var(--border);
}

.editorInput:focus,
.editorTextarea:focus,
textarea:focus,
.scenarioInlineSelect:focus,
.optionCard:focus-visible {
  box-shadow: 0 0 0 3px rgba(15, 23, 42, 0.5);
  border-color: rgba(15, 23, 42, 0.75);
}

.saveMessage.success,
.addBtn,
.addNodeBtn {
  background: #eaf7ef;
  color: #14532d;
  border-color: #14532d;
}

.saveMessage.error,
.deleteBtn,
.deleteNodeBtn,
.kebabMenuItem.danger {
  color: #991b1b;
}

.saveMessage.error,
.deleteBtn,
.deleteNodeBtn {
  background: #fdecec;
  border-color: #991b1b;
}

.duplicateBtn,
.infoMessage {
  background: #e8f0ff;
  color: #1e3a8a;
  border-color: #1e3a8a;
}

.warningMessage {
  background: #fff4db;
  color: #7c2d12;
  border-color: #7c2d12;
}

.actionChip.selected {
  border-color: var(--brand);
}

html[data-theme="dark"] .editorInput:focus,
html[data-theme="dark"] .editorTextarea:focus,
html[data-theme="dark"] textarea:focus,
html[data-theme="dark"] .scenarioInlineSelect:focus,
html[data-theme="dark"] .optionCard:focus-visible {
  box-shadow: 0 0 0 3px rgba(236, 240, 246, 0.35);
  border-color: rgba(236, 240, 246, 0.7);
}

html[data-theme="dark"] .saveMessage.success,
html[data-theme="dark"] .addBtn,
html[data-theme="dark"] .addNodeBtn {
  background: #113220;
  color: #bbf7d0;
  border-color: #86efac;
}

html[data-theme="dark"] .saveMessage.error,
html[data-theme="dark"] .deleteBtn,
html[data-theme="dark"] .deleteNodeBtn {
  background: #3a1414;
  color: #fecaca;
  border-color: #fca5a5;
}

html[data-theme="dark"] .duplicateBtn,
html[data-theme="dark"] .infoMessage {
  background: #1b2850;
  color: #dbeafe;
  border-color: #93c5fd;
}

html[data-theme="dark"] .warningMessage {
  background: #3c2a12;
  color: #ffedd5;
  border-color: #fdba74;
}

@media (max-width: 720px) {
  .overlayToast {
    top: 10px;
    max-width: calc(100vw - 16px);
    padding: 9px 14px;
  }

  .scenarioAccessGrid {
    grid-template-columns: 1fr;
  }
}