*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 20rem;
  background: var(--color-canvas);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-body);
  line-height: 1.47;
  letter-spacing: -0.023rem;
  text-rendering: optimizeLegibility;
}

button,
textarea {
  font: inherit;
}

a {
  color: var(--color-primary);
}

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

:focus-visible {
  outline: 2px solid var(--color-primary-focus);
  outline-offset: 3px;
  box-shadow: 0 0 0 4px var(--color-focus-halo);
}

button:active,
.button:active {
  transform: scale(0.95);
}

[hidden] {
  display: none !important;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: var(--space-sm);
  left: var(--space-sm);
  z-index: 100;
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-sm);
  background: var(--color-canvas);
  transform: translateY(-200%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--color-hairline);
  background: var(--color-frosted);
  backdrop-filter: saturate(180%) blur(20px);
}

.header-inner {
  width: min(100% - 2rem, var(--content-wide));
  min-height: var(--nav-height);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  color: var(--color-ink);
  font-size: var(--text-caption);
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}

.brand-mark {
  display: grid;
  width: 2rem;
  height: 2rem;
  place-items: center;
  border-radius: var(--radius-sm);
  background: var(--color-ink);
  color: var(--color-canvas);
  font-size: var(--text-fine);
  letter-spacing: 0;
}

.header-nav {
  display: flex;
  gap: var(--space-lg);
  margin-left: auto;
}

.header-nav a {
  color: var(--color-ink-soft);
  font-size: var(--text-caption);
  text-decoration: none;
}

.header-nav a:hover,
.text-button:hover {
  color: var(--color-primary);
}

.save-status {
  color: var(--color-ink-muted);
  font-size: var(--text-fine);
  white-space: nowrap;
}

.hero {
  background: var(--color-canvas-parchment);
}

.hero-inner {
  width: min(100% - 2rem, 70rem);
  margin: 0 auto;
  padding: clamp(4rem, 10vw, 8rem) 0 clamp(3.5rem, 8vw, 6rem);
  text-align: center;
}

.eyebrow,
.block-label {
  margin: 0 0 var(--space-sm);
  color: var(--color-primary);
  font-size: var(--text-fine);
  font-weight: 600;
  letter-spacing: 0.08em;
}

.hero h1 {
  max-width: 16ch;
  margin: 0 auto;
  font-family: var(--font-display);
  font-size: var(--text-hero);
  font-weight: 600;
  line-height: 1.07;
  letter-spacing: -0.025em;
  word-break: keep-all;
}

.hero-copy {
  max-width: 38rem;
  margin: var(--space-lg) auto 0;
  color: var(--color-ink-soft);
  font-family: var(--font-display);
  font-size: var(--text-lead);
  font-weight: 400;
  line-height: 1.5;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-sm);
  margin-top: var(--space-xl);
}

.button {
  min-height: 2.75rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  padding: 0.65rem 1.35rem;
  cursor: pointer;
  font-size: var(--text-caption);
  font-weight: 400;
  text-decoration: none;
  transition: color var(--transition-fast), background var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast);
}

.button-primary {
  background: var(--color-primary);
  color: var(--color-on-primary);
}

.button-secondary,
.button-completion {
  border-color: var(--color-primary);
  background: transparent;
  color: var(--color-primary);
}

.button-primary:hover {
  background: var(--color-primary-focus);
}

.button-secondary:hover,
.button-completion:hover,
.button-completion.is-complete {
  background: var(--color-primary);
  color: var(--color-on-primary);
}

.overall-progress {
  max-width: 34rem;
  margin: var(--space-xxl) auto 0;
  text-align: left;
}

.progress-copy {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  margin-bottom: var(--space-xs);
  font-size: var(--text-caption);
}

.progress-track {
  height: 0.375rem;
  overflow: hidden;
  border-radius: var(--radius-pill);
  background: var(--color-hairline);
}

.progress-track span {
  display: block;
  width: 0;
  height: 100%;
  border-radius: inherit;
  background: var(--color-primary);
  transition: width 240ms ease;
}

.certification-note {
  margin: var(--space-sm) 0 0;
  color: var(--color-ink-muted);
  font-size: var(--text-fine);
  line-height: 1.5;
}

.day-plan,
.quiz-section,
.cheatsheet-section,
.reset-section {
  width: min(100% - 2rem, 72rem);
  margin: 0 auto;
  padding: var(--space-section) 0;
}

.section-heading {
  max-width: 44rem;
  margin-bottom: var(--space-xxl);
}

.section-heading h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-display);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.section-heading > p:last-child {
  margin: var(--space-md) 0 0;
  color: var(--color-ink-muted);
}

.plan-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 1px;
  background: var(--color-hairline);
  list-style: none;
}

.plan-item {
  min-height: 11rem;
  padding: var(--space-lg);
  background: var(--color-canvas);
}

.plan-item button {
  width: 100%;
  height: 100%;
  padding: 0;
  border: 0;
  background: transparent;
  color: inherit;
  cursor: pointer;
  text-align: left;
}

.plan-number {
  color: var(--color-primary);
  font-size: var(--text-fine);
  font-weight: 600;
}

.plan-item h3 {
  margin: var(--space-md) 0 var(--space-xs);
  font-size: var(--text-body);
  font-weight: 600;
  line-height: 1.24;
}

.plan-item p {
  margin: 0;
  color: var(--color-ink-muted);
  font-size: var(--text-caption);
}

.curriculum {
  padding: var(--space-section) max(1rem, calc((100vw - var(--content-wide)) / 2));
  background: var(--color-dark);
  color: var(--color-canvas);
}

.section-heading-light {
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.section-heading-light .eyebrow {
  color: var(--color-primary-on-dark);
}

.workspace {
  display: grid;
  grid-template-columns: minmax(14rem, 18rem) minmax(0, 1fr);
  max-width: var(--content-wide);
  margin: 0 auto;
  border: 1px solid var(--color-ink-soft);
  background: var(--color-canvas);
  color: var(--color-ink);
}

.module-sidebar {
  min-width: 0;
  border-right: 1px solid var(--color-hairline);
  background: var(--color-canvas-parchment);
}

.sidebar-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-lg);
  border-bottom: 1px solid var(--color-hairline);
}

.sidebar-heading .eyebrow {
  margin: 0;
}

.sidebar-heading span {
  color: var(--color-ink-muted);
  font-size: var(--text-fine);
}

.module-nav-button {
  width: 100%;
  min-height: 5.5rem;
  display: grid;
  grid-template-columns: 1.75rem 1fr auto;
  gap: var(--space-sm);
  align-items: start;
  padding: var(--space-md) var(--space-lg);
  border: 0;
  border-bottom: 1px solid var(--color-hairline);
  background: transparent;
  color: var(--color-ink);
  cursor: pointer;
  text-align: left;
}

.module-nav-button:hover,
.module-nav-button[aria-current="page"] {
  background: var(--color-canvas);
}

.module-nav-button[aria-current="page"] {
  box-shadow: inset 3px 0 0 var(--color-primary);
}

.module-index,
.module-minutes {
  color: var(--color-ink-muted);
  font-size: var(--text-fine);
}

.module-name {
  font-size: var(--text-caption);
  font-weight: 600;
  line-height: 1.4;
}

.completion-dot {
  width: 0.625rem;
  height: 0.625rem;
  margin-top: 0.25rem;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-pill);
}

.module-nav-button.is-complete .completion-dot {
  border-color: var(--color-primary);
  background: var(--color-primary);
}

.lesson {
  min-width: 0;
  padding: clamp(1.5rem, 4vw, 3.5rem);
}

.lesson-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-xl);
  padding-bottom: var(--space-xl);
  border-bottom: 1px solid var(--color-hairline);
}

.lesson-meta {
  margin: 0 0 var(--space-sm);
  color: var(--color-primary);
  font-size: var(--text-caption);
  font-weight: 600;
}

.lesson h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-section);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.lesson-summary {
  max-width: 44rem;
  margin: var(--space-md) 0 0;
  color: var(--color-ink-muted);
}

.button-completion {
  flex: 0 0 auto;
}

.lesson-block,
.content-section {
  max-width: var(--content-reading);
  margin: var(--space-xxl) auto 0;
}

.lesson-block h3,
.content-section h3,
.quiz-result h3,
.missed-review h3,
.download-panel h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.015em;
}

.objectives {
  padding: var(--space-lg);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-lg);
  background: var(--color-canvas-parchment);
}

.objectives ul,
.content-section ul {
  margin: var(--space-md) 0 0;
  padding-left: 1.3rem;
}

.objectives li + li,
.content-section li + li {
  margin-top: var(--space-xs);
}

.content-section p {
  margin: var(--space-md) 0 0;
  white-space: pre-line;
}

.example {
  padding: var(--space-md) var(--space-lg);
  border-left: 3px solid var(--color-primary);
  background: var(--color-canvas-parchment);
  color: var(--color-ink-soft);
}

.practice {
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  background: var(--color-dark);
  color: var(--color-canvas);
}

.practice .block-label {
  color: var(--color-primary-on-dark);
}

.answer-reveal {
  margin-top: var(--space-lg);
  border-top: 1px solid var(--color-ink-soft);
  padding-top: var(--space-md);
}

.practice-download {
  min-height: 2.75rem;
  display: inline-flex;
  align-items: center;
  margin-top: var(--space-md);
  color: var(--color-primary-on-dark);
  font-weight: 600;
  text-decoration: none;
}

.answer-reveal summary {
  color: var(--color-primary-on-dark);
  cursor: pointer;
  font-weight: 600;
}

.answer-reveal p {
  white-space: pre-line;
}

.block-heading-row {
  display: flex;
  justify-content: space-between;
  gap: var(--space-lg);
  align-items: end;
}

.block-heading-row > p,
.block-heading-row > span {
  margin: 0;
  color: var(--color-ink-muted);
  font-size: var(--text-fine);
}

.source-list {
  display: grid;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
}

.source-card {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: var(--space-md);
  padding: var(--space-md) 0;
  border-top: 1px solid var(--color-hairline);
}

.source-card h4 {
  margin: 0;
  font-size: var(--text-body);
}

.source-card p {
  margin: var(--space-xs) 0 0;
  color: var(--color-ink-muted);
  font-size: var(--text-caption);
}

.source-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-top: var(--space-sm);
}

.source-chip {
  padding: var(--space-xxs) var(--space-sm);
  border-radius: var(--radius-pill);
  background: var(--color-canvas-parchment);
  color: var(--color-ink-soft);
  font-size: var(--text-fine);
}

.source-link {
  align-self: start;
  min-height: 2.75rem;
  display: inline-flex;
  align-items: center;
  white-space: nowrap;
  text-decoration: none;
}

.notes textarea {
  width: 100%;
  margin-top: var(--space-lg);
  resize: vertical;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
  background: var(--color-canvas-parchment);
  color: var(--color-ink);
  line-height: 1.6;
}

.notes textarea:focus {
  border-color: var(--color-primary-focus);
  background: var(--color-canvas);
}

.lesson-pager {
  max-width: var(--content-reading);
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  margin: var(--space-xxl) auto 0;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-hairline);
}

.text-button {
  min-height: 2.75rem;
  border: 0;
  background: transparent;
  color: var(--color-primary);
  cursor: pointer;
}

.text-button:disabled {
  color: var(--color-ink-muted);
  cursor: not-allowed;
}

.load-state,
.error-state {
  max-width: 44rem;
  margin: 0 auto;
  padding: var(--space-section) var(--space-lg);
  text-align: center;
}

.loader {
  display: inline-block;
  width: 2rem;
  height: 2rem;
  border: 2px solid var(--color-ink-soft);
  border-top-color: var(--color-primary-on-dark);
  border-radius: var(--radius-pill);
  animation: spin 800ms linear infinite;
}

.error-state h2 {
  margin: 0;
}

.error-state p:not(.eyebrow) {
  color: var(--color-dark-muted);
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.quiz-list {
  display: grid;
  gap: var(--space-lg);
}

.quiz-card {
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
}

.quiz-card legend {
  width: 100%;
  padding: 0;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.4;
}

.question-number {
  display: block;
  margin-bottom: var(--space-xs);
  color: var(--color-primary);
  font-family: var(--font-body);
  font-size: var(--text-fine);
  letter-spacing: 0.08em;
}

.options {
  display: grid;
  gap: var(--space-xs);
  margin-top: var(--space-lg);
}

.option {
  min-height: 3.25rem;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-sm) var(--space-md);
  cursor: pointer;
}

.option:hover,
.option:has(input:checked) {
  border-color: var(--color-primary);
}

.option input {
  width: 1.125rem;
  height: 1.125rem;
  accent-color: var(--color-primary);
}

.option.is-correct {
  border-width: 2px;
  border-color: var(--color-primary);
}

.option.is-wrong {
  border-style: dashed;
  border-color: var(--color-ink-muted);
}

.answer-feedback {
  margin: var(--space-md) 0 0;
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-hairline);
  color: var(--color-ink-soft);
}

.answer-feedback strong {
  color: var(--color-primary);
}

.quiz-actions {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  margin-top: var(--space-xl);
}

.quiz-actions p {
  margin: 0;
  color: var(--color-ink-muted);
}

.quiz-result,
.missed-review {
  margin-top: var(--space-xl);
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  background: var(--color-canvas-parchment);
}

.score {
  margin: var(--space-md) 0 var(--space-xs);
  color: var(--color-primary);
  font-family: var(--font-display);
  font-size: var(--text-display);
  font-weight: 600;
  line-height: 1;
}

.quiz-result .button {
  margin-top: var(--space-md);
}

.missed-item + .missed-item {
  margin-top: var(--space-lg);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-hairline);
}

.missed-item h4,
.cheat-card h3 {
  margin: 0;
  font-size: var(--text-body);
}

.missed-item p {
  margin: var(--space-xs) 0 0;
}

.cheatsheet-section {
  border-top: 1px solid var(--color-hairline);
}

.cheatsheet-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  padding: 1px;
  background: var(--color-hairline);
}

.cheat-card {
  padding: var(--space-xl);
  background: var(--color-canvas);
}

.cheat-card p {
  margin: var(--space-md) 0 0;
  white-space: pre-line;
}

.download-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-xl);
  margin-top: var(--space-xl);
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  background: var(--color-canvas-parchment);
}

.download-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: var(--space-sm);
}

.reset-section {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-xl);
  border-top: 1px solid var(--color-hairline);
}

.reset-section h2 {
  margin: 0;
  font-size: 1.5rem;
}

.reset-section p {
  margin: var(--space-xs) 0 0;
  color: var(--color-ink-muted);
}

footer {
  display: flex;
  justify-content: space-between;
  gap: var(--space-lg);
  padding: var(--space-xl) max(1rem, calc((100vw - 72rem) / 2));
  background: var(--color-canvas-parchment);
  color: var(--color-ink-muted);
  font-size: var(--text-fine);
}

dialog {
  width: min(calc(100% - 2rem), 30rem);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  color: var(--color-ink);
}

dialog::backdrop {
  background: var(--color-backdrop);
}

dialog h2 {
  margin: 0;
  font-size: 1.5rem;
}

dialog p {
  color: var(--color-ink-muted);
}

.dialog-actions {
  display: flex;
  justify-content: flex-end;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
}

@media (max-width: 64rem) {
  .plan-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .module-sidebar {
    border-right: 0;
    border-bottom: 1px solid var(--color-hairline);
  }

  #module-nav {
    width: 100%;
    min-width: 0;
    max-width: 100%;
    display: flex;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
  }

  .module-nav-button {
    min-width: 14rem;
    border-right: 1px solid var(--color-hairline);
    border-bottom: 0;
    scroll-snap-align: start;
  }

  .module-nav-button[aria-current="page"] {
    box-shadow: inset 0 -3px 0 var(--color-primary);
  }
}

@media (max-width: 46rem) {
  .header-nav,
  .save-status {
    display: none;
  }

  .header-inner {
    justify-content: center;
  }

  .lesson-header,
  .block-heading-row,
  .download-panel,
  .reset-section {
    align-items: stretch;
    flex-direction: column;
  }

  .button-completion {
    align-self: flex-start;
  }

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

  .download-links {
    justify-content: flex-start;
  }

  footer {
    flex-direction: column;
  }
}

@media (max-width: 30rem) {
  .plan-list {
    grid-template-columns: 1fr;
  }

  .hero-actions,
  .hero-actions .button,
  .quiz-actions,
  .quiz-actions .button,
  .dialog-actions,
  .dialog-actions .button {
    width: 100%;
  }

  .quiz-actions,
  .dialog-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .source-card {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

@media print {
  body {
    font-size: 11pt;
  }

  .site-header,
  .hero,
  .day-plan,
  .curriculum,
  .quiz-section,
  .reset-section,
  footer,
  .download-panel,
  .cheatsheet-section > .section-heading p:first-child,
  .cheatsheet-section > .section-heading p:last-child {
    display: none !important;
  }

  .cheatsheet-section {
    display: block !important;
    width: 100%;
    padding: 0;
    border: 0;
  }

  .cheatsheet-section > .section-heading {
    margin-bottom: 1.5rem;
  }

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

  .cheat-card {
    break-inside: avoid;
  }
}