.login-screen[hidden], #app-shell[hidden], #mobile-nav[hidden], #context-drawer[hidden], #drawer-backdrop[hidden], #student-nav[hidden], #staff-nav[hidden] { display: none; }
.page-header { display: flex; align-items: flex-end; justify-content: space-between; gap: var(--space-5); margin-bottom: var(--space-6); }
.page-header h1 { margin: 7px 0 8px; font-size: clamp(27px, 3vw, 38px); letter-spacing: -.055em; }
.page-header p { max-width: 700px; margin: 0; color: var(--text-secondary); font-size: 14px; line-height: 1.7; }
.ai-route { overflow-x: hidden; overflow-y: auto; }
.ai-page { min-height: 100%; display: block; }
.ai-page > .page-header { margin-bottom: 16px; }
.ai-page > .teacher-hero { min-height: 0; padding: 20px 24px; }
.ai-hero-actions { display: grid; gap: 9px; margin-top: 20px; }
.hero-action-primary, .hero-action-secondary { display: flex; flex-wrap: wrap; gap: 8px; }
.hero-action-primary { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.hero-action-secondary { justify-content: flex-start; }
.hero-action-secondary .button { padding-block: 7px; font-size: 12px; }
.ai-page > .stat-grid, .ai-page > .teacher-grid { display: grid; }
.ai-page > #ai-chat-root { min-height: 0; }
.ai-page .chat-shell { width: 100%; max-width: none; min-height: 500px; height: 500px; margin-top: 20px; }
@media (min-width: 1200px) {
  .ai-page .chat-shell { min-height: clamp(760px, 82dvh, 980px); height: clamp(760px, 82dvh, 980px); }
}
.compact-context-plan { gap: 0; margin-top: 8px; }
.compact-context-plan .plan-item { padding: 8px 0; }
.compact-context-plan .plan-index { width: 23px; height: 23px; font-size: 10px; }
.compact-context-plan .plan-item strong { font-size: 12px; }
.compact-context-plan .plan-item small { font-size: 11px; }
.page-actions { display: flex; align-items: center; gap: var(--space-2); flex-wrap: wrap; }
.button-small { min-height: 32px; padding: 6px 10px; font-size: 11px; }
.teacher-hero { display: grid; grid-template-columns: minmax(0, 1fr) 260px; gap: var(--space-5); padding: var(--space-7); border-radius: var(--radius-xl); color: #fff; background: var(--surface-dark); }
.teacher-hero h2 { max-width: 720px; margin: 10px 0; font-size: clamp(24px, 3vw, 34px); letter-spacing: -.045em; }
.teacher-hero p { max-width: 680px; margin: 0; color: #c3cde0; font-size: 14px; line-height: 1.75; }
.teacher-hero .eyebrow { color: #aebbd0; }
.hero-readiness { display: grid; align-content: center; gap: 8px; padding: var(--space-5); border: 1px solid rgba(255,255,255,.12); border-radius: var(--radius-lg); background: rgba(255,255,255,.06); }
.hero-readiness strong { font-size: 40px; letter-spacing: -.06em; }
.hero-readiness span { color: #b9c5d9; font-size: 12px; }
.teacher-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(260px, .42fr); gap: var(--space-5); margin-top: var(--space-5); }
.plan-list, .mastery-list, .course-list, .question-list, .staff-list { display: grid; gap: var(--space-3); }
.plan-item { display: flex; align-items: flex-start; gap: 12px; padding: 12px 0; border-bottom: 1px solid var(--border); }
.plan-item:last-child { border-bottom: 0; }
.plan-index { width: 28px; height: 28px; display: grid; place-items: center; flex: 0 0 auto; border-radius: 9px; color: var(--brand-strong); background: var(--brand-soft); font-size: 12px; font-weight: 800; }
.plan-item strong, .plan-item small { display: block; }
.plan-item strong { font-size: 13px; }
.plan-item small { margin-top: 4px; color: var(--text-secondary); font-size: 12px; }
.mastery-row { display: grid; gap: 7px; }
.mastery-row-head { display: flex; justify-content: space-between; gap: var(--space-3); font-size: 12px; }
.mastery-row-head span:last-child { color: var(--text-secondary); }
.chat-shell { display: grid; grid-template-rows: auto minmax(0, 1fr); min-height: calc(100dvh - 152px); max-width: var(--chat-max); margin: var(--space-5) auto 0; border: 1px solid var(--border); border-radius: var(--radius-lg); background: var(--surface); box-shadow: var(--shadow-sm); }
.chat-toolbar { display: flex; align-items: center; gap: 8px; overflow-x: auto; padding: 12px; border-bottom: 1px solid var(--border); }
.mode-tab { min-height: 40px; flex: 0 0 auto; border: 1px solid transparent; border-radius: 999px; padding: 8px 13px; color: var(--text-secondary); background: transparent; font-size: 12px; font-weight: 700; }
.mode-tab:hover { background: var(--surface-muted); }
.mode-tab.is-active { color: var(--brand-strong); background: var(--brand-soft); }
.chat-body { min-height: 0; display: grid; grid-template-rows: minmax(0, 1fr) auto; overflow: hidden; }
.chat-messages { min-height: 0; overflow-y: auto; padding: var(--space-6); scroll-behavior: smooth; }
.chat-message { display: flex; gap: 10px; max-width: 760px; margin: 0 auto 18px; }
.chat-message.user { justify-content: flex-end; }
.message-avatar { width: 30px; height: 30px; display: grid; place-items: center; flex: 0 0 auto; border-radius: 50%; color: #fff; background: var(--brand); font-size: 12px; font-weight: 800; }
.chat-message.user .message-avatar { order: 2; color: var(--brand-strong); background: var(--brand-soft); }
.message-bubble { min-width: 0; max-width: min(100%, 680px); padding: 13px 15px; border: 1px solid var(--border); border-radius: 14px; color: var(--text-primary); background: #fbfcfe; font-size: 15px; line-height: 1.75; white-space: pre-wrap; overflow-wrap: anywhere; }
.chat-message.user .message-bubble { border-color: var(--brand); color: #fff; background: var(--brand-strong); }
.chat-meta { margin-top: 6px; color: var(--text-tertiary); font-size: 11px; }
.chat-composer { display: grid; gap: 8px; padding: 12px; border-top: 1px solid var(--border); background: var(--surface); }
.composer-row { display: flex; align-items: flex-end; gap: 8px; }
.composer-row textarea { min-height: 44px; max-height: 150px; flex: 1; resize: none; border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 12px; color: var(--text-primary); background: var(--surface); line-height: 1.5; overflow-y: auto; }
.composer-row textarea:focus { border-color: var(--brand); outline: none; box-shadow: 0 0 0 3px rgba(72, 103, 217, .12); }
.composer-hint { display: flex; justify-content: space-between; gap: var(--space-3); color: var(--text-tertiary); font-size: 11px; }
.latest-button { position: sticky; z-index: 2; left: 50%; bottom: 10px; transform: translateX(-50%); display: block; width: fit-content; min-height: 36px; border: 1px solid var(--border); border-radius: 999px; padding: 7px 12px; color: var(--brand-strong); background: var(--surface); box-shadow: var(--shadow-sm); }
.latest-button[hidden] { display: none; }
.context-stack { display: grid; gap: var(--space-4); }
.context-card { padding: var(--space-4); }
.context-card h3 { margin: 6px 0 10px; font-size: 15px; }
.context-card p { margin: 0; color: var(--text-secondary); font-size: 12px; line-height: 1.6; }
.countdown { display: flex; align-items: baseline; gap: 7px; }
.countdown strong { font-size: 30px; letter-spacing: -.05em; }
.course-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-4); }
.course-card { display: grid; gap: 12px; min-width: 0; padding: var(--space-5); text-align: left; }
.course-card h3 { margin: 0; font-size: 16px; }
.course-card p { min-height: 42px; margin: 0; color: var(--text-secondary); font-size: 13px; line-height: 1.6; }
.course-meta { display: flex; flex-wrap: wrap; gap: 6px; color: var(--text-secondary); font-size: 12px; }
.course-card .button { width: 100%; }
.practice-layout { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: var(--space-5); }
.question-card { padding: var(--space-6); }
.question-card h2 { margin: 13px 0 18px; font-size: 20px; line-height: 1.6; }
.answer-list { display: grid; gap: 10px; }
.answer-option { display: flex; align-items: flex-start; gap: 10px; min-height: 48px; border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 12px; color: var(--text-primary); background: var(--surface); text-align: left; font-size: 14px; line-height: 1.5; }
.answer-option:hover, .answer-option.is-selected { border-color: var(--brand); background: var(--brand-soft); }
.answer-key { width: 24px; height: 24px; display: grid; place-items: center; flex: 0 0 auto; border-radius: 7px; color: var(--text-secondary); background: var(--surface-muted); font-size: 12px; font-weight: 800; }
.answer-option.is-selected .answer-key { color: #fff; background: var(--brand); }
.feedback { margin-top: 18px; padding: 15px; border-radius: var(--radius-md); line-height: 1.65; font-size: 14px; }
.feedback.correct { color: var(--success); background: var(--success-soft); }
.feedback.wrong { color: var(--danger); background: var(--danger-soft); }
.insight-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-5); }
.mastery-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
.mastery-card { padding: var(--space-5); }
.mastery-card h3 { margin: 0 0 14px; font-size: 14px; }
.mastery-score { display: flex; align-items: baseline; justify-content: space-between; gap: var(--space-3); margin-bottom: 10px; }
.mastery-score strong { font-size: 28px; letter-spacing: -.05em; }
.profile-grid { display: grid; grid-template-columns: minmax(0, 1fr) 360px; gap: var(--space-5); }
.staff-stats { margin-bottom: var(--space-5); }
.staff-row { display: grid; grid-template-columns: minmax(120px, 1.2fr) repeat(5, minmax(70px, .7fr)) auto; gap: 10px; align-items: center; padding: 13px 0; border-bottom: 1px solid var(--border); font-size: 12px; }
.staff-row:last-child { border-bottom: 0; }
.staff-row > * { min-width: 0; overflow-wrap: anywhere; }
.staff-row-head { color: var(--text-tertiary); font-size: 11px; }
.review-queue, .staff-detail-panel, .submission-review-panel { margin-top: var(--space-5); }
.staff-detail-panel h2, .submission-review-panel h2 { margin: 6px 0 0; }
.detail-metric-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; margin: 18px 0; }
.detail-metric-grid > div { display: grid; gap: 5px; padding: 13px; border-radius: 10px; background: var(--surface-muted); }
.detail-metric-grid span { color: var(--text-secondary); font-size: 11px; }
.detail-metric-grid strong { font-size: 22px; }
.detail-columns { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-5); }
.detail-columns h3 { margin: 0 0 10px; font-size: 14px; }
.submission-content { margin: 18px 0; padding: 15px; border: 1px solid var(--border); border-radius: 10px; background: var(--surface-muted); }
.submission-content p { margin: 8px 0; color: var(--text-secondary); line-height: 1.75; white-space: pre-wrap; }
.unit-content { min-width: 0; flex: 1; }
.unit-row-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 12px; }
.unit-row-head > div { min-width: 0; }
.unit-row small { display: block; margin-top: 5px; color: var(--text-tertiary); font-size: 11px; }
.unit-row.is-complete { border-color: rgba(34, 163, 126, .28); }
.unit-open { margin-top: 8px; }
.unit-detail { margin-top: 18px; padding: 18px; border: 1px solid var(--brand); border-radius: var(--radius-md); background: var(--brand-soft); }
.unit-detail-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 12px; }
.unit-detail-head h3 { margin: 6px 0 0; font-size: 18px; }
.unit-detail-body { margin-top: 12px; color: var(--text-secondary); line-height: 1.8; white-space: pre-wrap; }
.unit-detail-body .button { margin: 12px 8px 0 0; }
.unit-detail-actions { display: flex; align-items: center; gap: 12px; margin-top: 16px; padding-top: 14px; border-top: 1px solid rgba(72, 103, 217, .18); }
.settings-form { display: grid; gap: 14px; }
.settings-form .inline-fields { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.check-row { display: flex; align-items: center; gap: 9px; color: var(--text-secondary); font-size: 13px; }
.check-row input { width: 18px; height: 18px; accent-color: var(--brand); }
.mobile-only { display: none; }
.assessment-start { display: grid; grid-template-columns: 72px minmax(0, 1fr); gap: 20px; align-items: start; max-width: 860px; }
.assessment-start h2 { margin: 8px 0; font-size: 24px; }
.assessment-start p { max-width: 680px; line-height: 1.7; }
.assessment-start-mark { width: 64px; height: 64px; display: grid; place-items: center; border-radius: 18px; color: #fff; background: var(--brand-strong); font-size: 24px; font-weight: 800; }
.assessment-config { display: flex; flex-wrap: wrap; gap: 8px; margin: 18px 0; }
.assessment-config span { padding: 8px 10px; border-radius: 8px; color: var(--text-secondary); background: var(--surface-muted); font-size: 12px; }
.exam-card { max-width: 860px; margin: 0 auto; }
.exam-progress { display: grid; grid-template-columns: auto minmax(100px, 1fr) auto; align-items: center; gap: 12px; margin-bottom: 28px; color: var(--text-secondary); font-size: 12px; }
.exam-card h2 { margin: 12px 0 22px; font-size: clamp(20px, 2.2vw, 28px); line-height: 1.6; }
.exam-actions { justify-content: space-between; margin-top: 24px; }
.exam-timer { min-width: 92px; display: inline-grid; place-items: center; padding: 9px 13px; border-radius: 999px; color: var(--danger); background: var(--danger-soft); font-size: 14px; font-variant-numeric: tabular-nums; }
.assessment-result { max-width: 620px; margin: 0 auto; text-align: center; }
.assessment-result > strong { display: block; color: var(--brand-strong); font-size: 68px; letter-spacing: -.08em; }
.assessment-result > strong small { margin-left: 6px; color: var(--text-secondary); font-size: 16px; letter-spacing: 0; }
.assessment-result p { margin: 18px auto 0; color: var(--text-secondary); line-height: 1.7; }
.units-panel { margin-top: 24px; }
.unit-list, .task-list { display: grid; gap: 12px; }
.unit-list { margin-top: 16px; }
.unit-row { display: flex; align-items: flex-start; gap: 12px; padding: 14px 0; border-bottom: 1px solid var(--border); }
.unit-row:last-child { border-bottom: 0; }
.unit-icon { width: 34px; height: 34px; display: grid; place-items: center; flex: 0 0 auto; border-radius: 10px; color: var(--brand-strong); background: var(--brand-soft); font-size: 12px; font-weight: 800; }
.unit-row strong, .unit-row p, .unit-row small { display: block; }
.unit-row p { margin: 4px 0; color: var(--text-secondary); font-size: 13px; line-height: 1.6; }
.unit-row small { color: var(--text-tertiary); font-size: 11px; }
.task-card { display: grid; gap: 16px; padding: var(--space-6); }
.task-card h2 { margin: 6px 0 0; font-size: 19px; }
.task-card > p { margin: 0; color: var(--text-secondary); line-height: 1.75; }
.rubric-list { display: flex; flex-wrap: wrap; gap: 7px; }
.rubric-list span { padding: 7px 9px; border-radius: 8px; color: var(--text-secondary); background: var(--surface-muted); font-size: 11px; }
.task-form { display: grid; gap: 12px; padding-top: 16px; border-top: 1px solid var(--border); }
.task-form textarea { resize: vertical; min-height: 120px; }
.score-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-4); }
.score-card { display: grid; gap: 9px; min-width: 0; padding: var(--space-5); }
.score-card > span { color: var(--text-secondary); font-size: 12px; }
.score-card > strong { font-size: 34px; letter-spacing: -.06em; }
.score-card > small { color: var(--text-tertiary); font-size: 11px; }
.report-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-5); margin-top: var(--space-5); }
.operations-panel { margin-top: var(--space-5); }
.admin-workspace { margin-top: var(--space-5); }
.workspace-tabs { display: flex; gap: 6px; overflow-x: auto; margin: 18px 0; padding-bottom: 4px; border-bottom: 1px solid var(--border); }
.workspace-tab { flex: 0 0 auto; min-height: 36px; border: 1px solid transparent; border-radius: 999px; padding: 7px 13px; color: var(--text-secondary); background: transparent; font-size: 12px; font-weight: 700; }
.workspace-tab:hover, .workspace-tab.is-active { border-color: rgba(72, 103, 217, .22); color: var(--brand-strong); background: var(--brand-soft); }
.admin-workspace-content { min-height: 120px; }
.admin-data-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; margin-bottom: 10px; }
.admin-data-head > span { color: var(--text-tertiary); font-size: 12px; }
.admin-data-list { display: grid; gap: 0; }
.admin-data-row { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(100px, .8fr) minmax(100px, .8fr); align-items: center; gap: 12px; padding: 12px 0; border-bottom: 1px solid var(--border); color: var(--text-secondary); font-size: 12px; }
.admin-data-row:last-child { border-bottom: 0; }
.admin-data-row strong { min-width: 0; color: var(--text-primary); overflow-wrap: anywhere; }
.admin-data-row strong small { display: block; margin-top: 4px; color: var(--text-tertiary); font-weight: 400; }
.class-report-panel { margin-top: 16px; padding-top: 14px; border-top: 1px solid var(--border); }
.operations-stats { grid-template-columns: repeat(4, minmax(0, 1fr)); margin: 18px 0; }
.operations-stats > div { display: grid; gap: 4px; padding: 14px; border-radius: 10px; background: var(--surface-muted); }
.operations-stats strong { font-size: 24px; letter-spacing: -.05em; }
.operations-stats span { color: var(--text-secondary); font-size: 11px; }
@media (max-width: 1199px) {
  .app-shell { grid-template-columns: minmax(0, 1fr); }
  .desktop-sidebar { position: fixed; z-index: 32; inset: 0 auto 0 0; width: 240px; transform: translateX(-102%); transition: transform .2s ease; box-shadow: var(--shadow-md); }
  .desktop-sidebar.is-open { transform: translateX(0); }
  .topbar { position: relative; z-index: 1; }
  .app-shell.sidebar-open .topbar { z-index: 34; }
  .sidebar-backdrop:not([hidden]) { position: fixed; z-index: 31; inset: 0; display: block; background: rgba(20, 33, 61, .35); }
  .context-panel { display: none; }
  .tablet-only { display: inline-grid; }
  .context-toggle { display: inline-flex; }
  .context-drawer { position: fixed; z-index: 31; top: 0; right: 0; bottom: 0; width: min(360px, 92%); overflow-y: auto; padding: 24px; border-left: 1px solid var(--border); background: var(--surface); box-shadow: var(--shadow-md); }
  .context-drawer:not([hidden]) { display: block; }
  .drawer-backdrop:not([hidden]) { position: fixed; z-index: 30; inset: 0; display: block; background: rgba(20, 33, 61, .35); }
  .teacher-grid, .practice-layout, .profile-grid { grid-template-columns: 1fr; }
  .report-grid { grid-template-columns: 1fr; }
}
@media (max-width: 767px) {
  .login-screen { display: block; }
  .login-intro { min-height: 260px; padding: 28px 20px; }
  .login-intro-copy { margin-top: 30px; }
  .login-intro-copy h1 { font-size: 34px; }
  .login-intro-copy p, .login-trust { display: none; }
  .login-panel { min-height: calc(100dvh - 260px); width: 100%; padding: 28px 20px calc(36px + env(safe-area-inset-bottom)); }
  .login-panel > .brand-lockup { display: none; }
  .login-copy h2 { font-size: 26px; }
  .desktop-sidebar { display: none; }
  .tablet-only { display: none; }
  .app-shell { display: block; min-height: 100dvh; }
  .app-frame { min-height: 100dvh; display: block; }
  .topbar { min-height: 64px; padding: 0 12px; padding-top: env(safe-area-inset-top); }
  .topbar-title .eyebrow { display: none; }
  .topbar-actions { gap: 1px; }
  .context-toggle { display: inline-flex; width: 36px; min-width: 36px; height: 36px; align-items: center; justify-content: center; padding: 0; font-size: 0; }
  .context-toggle-label { display: none; }
  .context-toggle-icon { font-size: 21px; line-height: 1; }
  .user-chip { max-width: 92px; font-size: 12px; }
  .app-main { min-height: calc(100dvh - 64px); padding: 22px 16px calc(92px + env(safe-area-inset-bottom)); }
  .app-main.ai-route { min-height: calc(100dvh - 64px); overflow-y: auto; padding-bottom: calc(92px + env(safe-area-inset-bottom)); }
  .mobile-bottom-nav { position: fixed; z-index: 20; right: 0; bottom: 0; left: 0; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); padding: 6px 6px calc(6px + env(safe-area-inset-bottom)); border-top: 1px solid var(--border); background: rgba(255,255,255,.96); backdrop-filter: blur(12px); }
  .mobile-bottom-nav .nav-item { min-height: 48px; display: grid; justify-items: center; align-content: center; gap: 3px; padding: 5px 2px; color: var(--text-tertiary); text-align: center; font-size: 10px; }
  .mobile-bottom-nav .nav-item.is-active { color: var(--brand-strong); background: var(--brand-soft); }
  .mobile-bottom-nav .nav-icon { width: auto; font-size: 17px; }
  .page-header { align-items: flex-start; flex-direction: column; margin-bottom: var(--space-5); }
  .page-header h1 { font-size: 28px; }
  .page-actions { width: 100%; }
  .page-actions .button { flex: 1; }
  .teacher-hero { grid-template-columns: 1fr; padding: var(--space-5); }
  .ai-page > .teacher-hero { padding: 16px; }
  .ai-page > .teacher-hero { min-height: auto; }
  .ai-page > .page-header { display: none; }
  .ai-page > .teacher-hero h2 { margin: 7px 0; font-size: 21px; }
  .ai-page > .teacher-hero p { font-size: 13px; line-height: 1.55; }
  .ai-page > .teacher-hero .ai-hero-actions { margin-top: 12px; }
  .ai-page > .teacher-hero .ai-hero-actions { display: grid; grid-template-columns: 1fr; gap: 8px; }
  .ai-page > .teacher-hero .hero-action-primary, .ai-page > .teacher-hero .hero-action-secondary { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; }
  .ai-page > .teacher-hero .ai-hero-actions .button { width: 100%; min-width: 0; flex: none; padding-inline: 9px; }
  .ai-page > .teacher-hero .hero-action-primary .button:first-child { grid-column: 1 / -1; }
  .teacher-hero h2 { font-size: 25px; }
  .hero-readiness { grid-template-columns: auto 1fr; align-items: center; }
  .hero-readiness .progress { grid-column: 1 / -1; width: 100%; }
  .hero-readiness strong { font-size: 32px; }
  .stat-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
  .stat-card { padding: 14px; }
  .stat-card strong { font-size: 23px; }
  .chat-shell { min-height: calc(100dvh - 154px); margin-top: 14px; border-radius: var(--radius-md); }
  .ai-page .chat-shell { min-height: 0; margin-top: 12px; margin-bottom: 10px; }
  .ai-page .chat-shell { min-height: 430px; height: 430px; }
  .chat-toolbar { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); overflow: visible; gap: 6px; padding: 8px; }
  .mode-tab { width: 100%; min-width: 0; padding-inline: 5px; white-space: nowrap; }
  .chat-messages { padding: 16px 12px; }
  .chat-message { margin-bottom: 14px; }
  .message-bubble { font-size: 15px; }
  .composer-row textarea { max-height: 140px; }
  .composer-row .button { padding-inline: 12px; }
  .course-grid, .insight-grid, .mastery-grid { grid-template-columns: 1fr; }
  .assessment-start { grid-template-columns: 1fr; padding: 17px; }
  .assessment-start h2 { font-size: 20px; }
  .assessment-start-mark { width: 48px; height: 48px; border-radius: 13px; font-size: 18px; }
  .exam-progress { grid-template-columns: 1fr auto; gap: 8px; }
  .exam-progress .progress { grid-column: 1 / -1; grid-row: 2; }
  .exam-card { padding: 17px; }
  .exam-card h2 { font-size: 19px; }
  .exam-actions .button { flex: 1; }
  .task-card { padding: 17px; }
  .score-grid { grid-template-columns: 1fr; gap: 10px; }
  .operations-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; }
  .score-card { padding: 16px; }
  .score-card > strong { font-size: 29px; }
  .report-grid { margin-top: 16px; }
  .course-card, .card-pad, .question-card { padding: 17px; }
  .question-card h2 { font-size: 18px; }
  .staff-row { grid-template-columns: minmax(0, 1fr) auto; gap: 6px 12px; padding: 15px 0; }
  .staff-row-head { display: none; }
  .staff-row > span:not(:first-child) { font-size: 11px; }
  .staff-mobile-nav { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .detail-metric-grid { gap: 7px; }
  .detail-metric-grid > div { padding: 11px 9px; }
  .detail-metric-grid strong { font-size: 18px; }
  .detail-columns { grid-template-columns: 1fr; gap: 18px; }
  .admin-data-row { grid-template-columns: minmax(0, 1fr) auto; gap: 7px 12px; }
  .admin-data-row > *:last-child { grid-column: 2; }
  .unit-row-head { display: block; }
  .unit-row-head .badge { margin-top: 8px; }
  .unit-detail-actions { align-items: flex-start; flex-direction: column; }
  .settings-form .inline-fields { grid-template-columns: 1fr; }
  .context-drawer { padding: 20px 16px calc(24px + env(safe-area-inset-bottom)); }
}
@media (min-width: 768px) and (max-width: 1199px) {
  .mobile-bottom-nav { display: none; }
}
@media (min-width: 1200px) and (max-height: 760px) {
  .app-main.ai-route { padding-top: 20px; padding-bottom: 20px; }
  .ai-page > .page-header { display: none; }
  .ai-page > .teacher-hero { padding: 16px 20px; }
  .ai-page > .teacher-hero h2 { margin: 7px 0; font-size: 28px; }
  .ai-page > .teacher-hero p { line-height: 1.5; }
  .ai-page > .teacher-hero .ai-hero-actions { margin-top: 12px; }
  .ai-page .chat-shell { margin-top: 12px; }
}