@import url("./tokens.css");
@import url("https://fonts.googleapis.com/css2?family=Poppins:wght@400;500;600;700&display=swap");

:root {
  --color-bg: var(--color-cream);
  --color-surface: #ffffff;
  --color-text: #4b3f42;
  --color-text-strong: #5d4b4f;
  --color-border: var(--color-sand);
  --color-nav-bg: var(--color-sand);
  --color-nav-bg-hover: var(--color-clay);

  --shadow-sm: 0 10px 30px rgba(15, 23, 42, 0.08);

  --radius-sm: 6px;
  --radius-md: 8px;

  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;

  --content-width: 900px;
}

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

html {
  font-size: 16px;
}

body {
  margin: 0;
  font-family: "Poppins", Arial, sans-serif;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
}

.site-shell {
  min-height: 100vh;
}

.site-shell--sidebar {
  padding-left: 0;
}

.site-header,
.page-content {
  padding: var(--space-5);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  box-shadow: var(--shadow-sm);
}

.site-header {
  border: 1px solid var(--color-border);
}

.site-sidebar {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 60;
  width: 240px;
  height: 100vh;
  padding: var(--space-5) var(--space-4);
  overflow-y: auto;
  border-width: 0 1px 0 0;
  border-radius: 0;
  background: rgba(255, 255, 255, 0.92);
  border-right: 1px solid rgba(214, 206, 147, 0.9);
}

.site-sidebar__inner {
  display: grid;
  gap: var(--space-4);
}

.site-title {
  margin: 0 0 var(--space-4);
  font-size: 1.1rem;
}

.site-nav {
  display: grid;
  gap: var(--space-4);
}

.nav-section {
  display: grid;
  gap: var(--space-2);
}

.nav-section-trigger {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  width: 100%;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--color-text-strong);
  font: inherit;
  cursor: pointer;
  text-align: left;
}

.nav-chevron {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1rem;
  height: 1rem;
  flex: 0 0 1rem;
  font-size: 0;
  line-height: 0;
  color: var(--color-clay);
  transition: transform 160ms ease;
}

.nav-chevron::before {
  content: "";
  width: 0.45rem;
  height: 0.45rem;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(-45deg);
  transition: transform 160ms ease;
}

.nav-section-trigger[aria-expanded="true"] .nav-chevron::before {
  transform: rotate(45deg);
}

.nav-label {
  margin: 0;
  min-width: 0;
  flex: 1 1 auto;
  font-size: 0.88rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-olive);
}

.nav-section-panel {
  display: grid;
  gap: var(--space-3);
  padding-left: calc(1rem + var(--space-2));
}

.nav-section-panel[hidden] {
  display: none;
}

.nav-group {
  display: grid;
  gap: var(--space-2);
}

.nav-group-label {
  margin: var(--space-3) 0 0;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-rose);
  opacity: 0.78;
}

.nav-group:first-child .nav-group-label {
  margin-top: 0;
}

.nav-links {
  display: grid;
  gap: 2px;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  padding: 6px 8px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--color-text-strong);
  background: transparent;
  font-size: 13px;
  line-height: 1.35;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.nav-link:hover,
.nav-link:focus {
  background: rgba(216, 164, 143, 0.2);
  border-color: rgba(216, 164, 143, 0.45);
  color: var(--color-text-strong);
  transform: translateX(2px);
}

.nav-home {
  color: var(--color-text-strong);
}

.nav-home:hover,
.nav-home:focus {
  background: rgba(163, 163, 128, 0.16);
  border-color: rgba(163, 163, 128, 0.3);
}

.nav-quiz {
  color: var(--color-text-strong);
}

.nav-quiz:hover,
.nav-quiz:focus {
  background: rgba(187, 133, 136, 0.14);
  border-color: rgba(187, 133, 136, 0.28);
}

.nav-link.is-active,
.nav-link[aria-current="page"] {
  padding-left: 6px;
  border-left-color: var(--color-clay);
  border-left-width: 3px;
  background: rgba(216, 164, 143, 0.12);
  color: var(--color-text-strong);
  box-shadow: none;
}

.nav-link__label {
  min-width: 0;
  flex: 1 1 auto;
  overflow: hidden;
  text-overflow: ellipsis;
}

.nav-status-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 7px;
  border-radius: 999px;
  background: #a7a7a7;
}

.nav-status-dot.is-current {
  background: var(--color-clay);
}

.nav-status-dot.is-visited {
  background: var(--color-olive);
}

.nav-status-dot.is-default {
  background: var(--color-sand);
}

.page-content {
  width: calc(100vw - 240px);
  max-width: none;
  margin: 0;
  border: 1px solid var(--color-border);
}

.site-shell--sidebar .page-content {
  min-height: 100vh;
  margin-left: 240px;
  padding: var(--space-6);
  border-radius: 0;
  border-width: 0 0 0 1px;
}

.page-content > * {
  max-width: 750px;
}

.home-hero {
  display: grid;
  gap: var(--space-3);
  margin-bottom: var(--space-6);
}

.home-eyebrow,
.section-label {
  margin: 0;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-clay);
}

.home-subtitle {
  margin: 0;
}

.jump-button {
  justify-self: start;
  padding: 10px 14px;
  border: 1px solid var(--color-clay);
  border-radius: var(--radius-sm);
  background: rgba(216, 164, 143, 0.12);
  color: var(--color-text-strong);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease;
}

.jump-button:hover,
.jump-button:focus {
  background: rgba(216, 164, 143, 0.22);
  border-color: var(--color-rose);
}

.jump-button:disabled {
  cursor: not-allowed;
  opacity: 0.65;
}

.units-overview {
  display: grid;
  gap: var(--space-3);
}

.unit-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
  max-width: 750px;
}

.unit-card {
  display: grid;
  gap: 8px;
  min-height: 180px;
  padding: var(--space-4);
  border: 1px solid rgba(214, 206, 147, 0.9);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.78);
  color: inherit;
  text-decoration: none;
  transition: transform 160ms ease, border-color 160ms ease, background-color 160ms ease;
}

.unit-card:hover,
.unit-card:focus {
  transform: translateY(-2px);
  border-color: var(--color-clay);
  background: rgba(216, 164, 143, 0.12);
}

.unit-card--muted {
  opacity: 0.62;
}

.unit-card--muted:hover,
.unit-card--muted:focus {
  transform: none;
  border-color: rgba(214, 206, 147, 0.9);
  background: rgba(255, 255, 255, 0.78);
}

.unit-card__number,
.unit-card__description,
.unit-card__meta,
.home-footer-note {
  margin: 0;
}

.unit-card__number {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-clay);
}

.unit-card__title {
  margin: 0;
  font-size: 1.1rem;
}

.unit-card__description {
  font-size: 0.95rem;
  line-height: 1.45;
}

.unit-card__meta {
  margin-top: auto;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--color-text-strong);
}

.home-footer-note {
  margin-top: var(--space-6);
  font-size: 0.92rem;
  color: rgba(93, 75, 79, 0.78);
}

.sidebar-toggle {
  position: fixed;
  top: var(--space-4);
  left: var(--space-4);
  z-index: 60;
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.94);
  color: var(--color-text-strong);
  box-shadow: var(--shadow-sm);
  font: inherit;
  cursor: pointer;
}

.sidebar-toggle__icon {
  position: relative;
  width: 16px;
  height: 12px;
  display: inline-block;
  background:
    linear-gradient(currentColor 0 0) top / 100% 2px no-repeat,
    linear-gradient(currentColor 0 0) center / 100% 2px no-repeat,
    linear-gradient(currentColor 0 0) bottom / 100% 2px no-repeat;
}

.sidebar-backdrop {
  position: fixed;
  inset: 0;
  z-index: 50;
  background: rgba(75, 63, 66, 0.38);
}

.sidebar-backdrop[hidden] {
  display: none;
}

.mobile-page-bar {
  display: none;
}

.page-sequence-nav {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-3);
  margin-top: var(--space-6);
}

.page-sequence-link {
  display: grid;
  gap: 4px;
  padding: 12px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: rgba(239, 235, 206, 0.45);
  color: var(--color-text-strong);
  text-decoration: none;
  min-height: 64px;
}

.page-sequence-link:hover,
.page-sequence-link:focus {
  background: rgba(216, 164, 143, 0.16);
  border-color: rgba(216, 164, 143, 0.45);
}

.page-sequence-link--next {
  text-align: right;
}

.page-sequence-link__eyebrow {
  font-size: 0.73rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-clay);
}

.page-sequence-link__title {
  line-height: 1.35;
}

.table-scroll {
  width: 100%;
  overflow-x: auto;
  margin: 0 0 var(--space-5);
  -webkit-overflow-scrolling: touch;
}

.table-scroll table {
  margin-bottom: 0;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-top: var(--space-6);
  padding-top: var(--space-5);
  border-top: 1px solid var(--color-border);
}

.site-footer__text {
  margin: 0;
  color: rgba(93, 75, 79, 0.82);
}

.site-footer__link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: rgba(239, 235, 206, 0.45);
  color: var(--color-text-strong);
  text-decoration: none;
  font-weight: 600;
}

.site-footer__link:hover,
.site-footer__link:focus {
  background: rgba(216, 164, 143, 0.16);
  border-color: rgba(216, 164, 143, 0.45);
}

@media (max-width: 767px) {
  .site-shell--sidebar {
    padding-left: 0;
  }

  .site-sidebar {
    width: min(80vw, 300px);
    padding: calc(var(--space-6) + 18px) var(--space-4) var(--space-5);
    transform: translateX(-100%);
    transition: transform 180ms ease;
  }

  body.is-sidebar-open .site-sidebar {
    transform: translateX(0);
  }

  .site-shell--sidebar .page-content {
    width: 100%;
    margin-left: 0;
    padding: calc(var(--space-6) + 72px) var(--space-4) var(--space-5);
    border-width: 0;
  }

  .sidebar-toggle {
    display: inline-flex;
    top: 12px;
    left: 12px;
    padding: 10px;
  }

  .sidebar-toggle__label {
    display: none;
  }

  .mobile-page-bar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 55;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-3);
    min-height: 60px;
    padding: 10px 16px 10px 60px;
    border-bottom: 1px solid rgba(214, 206, 147, 0.9);
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(10px);
  }

  .mobile-page-bar--title-only {
    justify-content: flex-start;
  }

  .mobile-page-bar__title {
    margin: 0;
    min-width: 0;
    font-size: 0.92rem;
    font-weight: 600;
    line-height: 1.25;
    color: var(--color-text-strong);
  }

  .mobile-page-bar__home {
    flex: 0 0 auto;
    padding: 8px 10px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    text-decoration: none;
    background: rgba(239, 235, 206, 0.45);
  }

  .site-title {
    margin-bottom: var(--space-3);
  }

  .site-nav {
    gap: var(--space-3);
  }

  .nav-section-trigger {
    align-items: flex-start;
    padding: 6px 0;
  }

  .nav-label {
    white-space: normal;
    line-height: 1.3;
  }

  .nav-section-panel {
    padding-left: calc(0.8rem + var(--space-2));
  }

  .nav-link {
    align-items: flex-start;
    padding: 10px 8px;
    font-size: 14px;
    white-space: normal;
    overflow: visible;
    text-overflow: clip;
  }

  .nav-link__label {
    white-space: normal;
    overflow: visible;
    text-overflow: clip;
    line-height: 1.35;
  }

  .review-drawers {
    gap: var(--space-4);
  }

  .drawer-trigger {
    align-items: flex-start;
    padding: 14px 16px;
    line-height: 1.4;
  }

  .drawer-trigger::after {
    flex: 0 0 auto;
    margin-top: 2px;
  }

  .page-sequence-nav {
    grid-template-columns: 1fr;
  }

  .page-sequence-link--next {
    text-align: left;
  }

  .table-scroll table {
    min-width: 520px;
  }

  .home-hero {
    gap: var(--space-2);
    margin-bottom: var(--space-5);
  }

  .home-hero h1 {
    font-size: 1.75rem;
    line-height: 1.15;
    max-width: 18ch;
  }

  .home-subtitle {
    font-size: 0.98rem;
    line-height: 1.55;
    max-width: 34ch;
  }

  .jump-button {
    width: 100%;
    justify-self: stretch;
    text-align: center;
    min-height: 44px;
  }

  .units-overview {
    gap: var(--space-4);
  }

  .unit-grid {
    grid-template-columns: 1fr;
    gap: var(--space-3);
  }

  .unit-card {
    min-height: 0;
    gap: 10px;
    padding: 14px;
  }

  .unit-card__title {
    font-size: 1rem;
    line-height: 1.25;
  }

  .unit-card__description {
    font-size: 0.92rem;
    line-height: 1.5;
  }

  .unit-card__meta {
    font-size: 0.8rem;
  }

  .home-footer-note {
    margin-top: var(--space-5);
    font-size: 0.88rem;
    line-height: 1.5;
  }

  .site-footer {
    flex-direction: column;
    align-items: flex-start;
    margin-top: var(--space-5);
    padding-top: var(--space-4);
  }

  .site-footer__link {
    width: 100%;
    min-height: 44px;
  }
}

@media (min-width: 768px) {
  .sidebar-backdrop {
    display: none;
  }
}

.review-drawers {
  display: grid;
  gap: var(--space-3);
}

.review-drawer {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: rgba(239, 235, 206, 0.45);
  overflow: hidden;
}

.drawer-trigger {
  width: 100%;
  padding: var(--space-4);
  border: 0;
  background: transparent;
  color: var(--color-text-strong);
  font: inherit;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.drawer-trigger::after {
  content: "+";
  font-size: 1.1rem;
  line-height: 1;
}

.drawer-trigger[aria-expanded="true"]::after {
  content: "-";
}

.drawer-trigger:hover,
.drawer-trigger:focus {
  background: rgba(216, 164, 143, 0.18);
}

.drawer-panel {
  padding: 0 var(--space-4) var(--space-4);
  border-top: 1px solid var(--color-border);
  background: #ffffff;
}

.drawer-panel > :last-child {
  margin-bottom: 0;
}

.lesson-review-content {
  display: grid;
  gap: var(--space-4);
}

.lesson-review-content .question {
  display: grid;
  gap: var(--space-2);
  padding: var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: rgba(239, 235, 206, 0.42);
}

.lesson-review-content .question p {
  margin: 0;
}

.lesson-review-content .question > p:first-child {
  color: var(--color-text-strong);
  font-weight: 700;
}

.lesson-review-content .question ul {
  margin: 0;
  padding-left: 1.25rem;
}

.lesson-review-content .question li {
  margin: 3px 0;
}

.lesson-review-content .correct {
  color: var(--color-olive);
  font-weight: 700;
}

.lesson-review-content .note {
  padding-top: var(--space-2);
  border-top: 1px solid rgba(214, 206, 147, 0.65);
  color: rgba(93, 75, 79, 0.82);
  font-size: 0.92rem;
}

.flashcard-review {
  display: grid;
  gap: var(--space-3);
  margin-top: var(--space-5);
  padding-top: var(--space-5);
  border-top: 1px solid var(--color-border);
}

.flashcard-review h2,
.flashcard-counter {
  margin: 0;
}

.flashcard-counter {
  color: rgba(93, 75, 79, 0.78);
  font-size: 0.92rem;
}

.flashcard-card {
  display: grid;
  gap: var(--space-3);
  width: 100%;
  min-height: 200px;
  padding: var(--space-5);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: #ffffff;
  color: var(--color-text);
  box-shadow: var(--shadow-sm);
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: border-color 160ms ease, background-color 160ms ease, transform 160ms ease;
}

.flashcard-card:hover,
.flashcard-card:focus {
  border-color: var(--color-clay);
  transform: translateY(-1px);
}

.flashcard-card.is-flipped {
  border-color: rgba(163, 163, 128, 0.75);
  background: rgba(239, 235, 206, 0.35);
}

.flashcard-label {
  color: var(--color-clay);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.flashcard-text {
  color: var(--color-text-strong);
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.45;
}

.flashcard-detail {
  color: rgba(93, 75, 79, 0.82);
}

.flashcard-controls {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.flashcard-controls button {
  min-height: 40px;
  padding: 8px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.82);
  color: var(--color-text-strong);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}

.flashcard-controls button:hover,
.flashcard-controls button:focus {
  border-color: var(--color-clay);
  background: rgba(216, 164, 143, 0.16);
}

table {
  width: 100%;
  margin: 0 0 var(--space-5);
  border-collapse: collapse;
}

thead {
  background: var(--color-olive);
  color: #ffffff;
}

th,
td {
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--color-border);
  text-align: left;
  vertical-align: top;
}
h1,
h2,
h3 {
  margin-top: 0;
  color: var(--color-text-strong);
}