:root {
  --bg-1: #fff7fb;
  --bg-2: #eef7ff;
  --card: rgba(255, 255, 255, 0.86);
  --primary: #7c4dff;
  --primary-dark: #5a2de0;
  --secondary: #ff7bbd;
  --accent: #67d7ff;
  --navy: #1f2a60;
  --text: #22304f;
  --muted: #5d6786;
  --line: rgba(124, 77, 255, 0.12);
  --shadow: 0 24px 60px rgba(124, 77, 255, 0.16);
  --success: #1dbf73;
  --warning: #ffb648;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: 'Cairo', sans-serif;
  background: linear-gradient(135deg, var(--bg-1), var(--bg-2));
  color: var(--text);
  direction: ltr;
  text-align: left;
}

a {
  text-decoration: none;
}

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

.container {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.section-spacing {
  padding: 92px 0;
}

.page-bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(circle at top left, rgba(124, 77, 255, 0.12), transparent 28%),
    radial-gradient(circle at bottom right, rgba(103, 215, 255, 0.18), transparent 25%);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(16px);
  background: rgba(255, 255, 255, 0.5);
  border-bottom: 1px solid rgba(124, 77, 255, 0.08);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 20px 0;
}

.brand-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-mark {
  width: 50px;
  height: 50px;
  display: grid;
  place-items: center;
  border-radius: 16px;
  background: linear-gradient(135deg, rgba(124, 77, 255, 0.08), rgba(103, 215, 255, 0.08));
  border: 1px solid rgba(124, 77, 255, 0.08);
}

.brand-mark svg {
  width: 100%;
  height: 100%;
  display: block;
}

.brand-name {
  margin: 0;
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--navy);
}

.brand-wrap small {
  color: var(--muted);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.main-nav a {
  color: var(--muted);
  font-weight: 600;
}

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--navy);
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

.nav-btn,
.primary-btn,
.secondary-btn,
.card-btn,
.back-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 14px;
  font-weight: 700;
  transition: 0.25s ease;
}

.nav-btn,
.primary-btn,
.card-btn {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  box-shadow: 0 14px 26px rgba(124, 77, 255, 0.24);
}

.nav-btn {
  padding: 12px 22px;
}

.primary-btn,
.card-btn {
  padding: 16px 26px;
}

.secondary-btn,
.back-btn {
  padding: 16px 24px;
  background: #fff;
  border: 1px solid var(--line);
  color: var(--navy);
}

.nav-btn:hover,
.primary-btn:hover,
.secondary-btn:hover,
.card-btn:hover,
.back-btn:hover {
  transform: translateY(-2px);
}

.hero {
  padding: 72px 0 56px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 42px;
  align-items: center;
}

.eyebrow {
  display: inline-block;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(124, 77, 255, 0.1);
  color: var(--primary-dark);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero-copy h1 {
  margin: 20px 0 16px;
  font-size: 3.4rem;
  line-height: 1.05;
  letter-spacing: 0;
  color: var(--navy);
}

.hero-copy p {
  font-size: 1.08rem;
  line-height: 1.9;
  color: var(--muted);
  max-width: 620px;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-top: 28px;
}

.mini-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  margin-top: 30px;
}

.mini-stats div {
  min-width: 110px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 16px 18px;
}

.mini-stats strong {
  display: block;
  font-size: 1.5rem;
  color: var(--navy);
}

.mini-stats span {
  display: block;
  color: var(--muted);
  font-size: 0.82rem;
  margin-top: 6px;
}

.hero-card {
  background: rgba(255, 255, 255, 0.88);
  border: 1px solid var(--line);
  border-radius: 32px;
  padding: 26px 22px;
  box-shadow: var(--shadow);
}

.card-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
}

.tag {
  display: inline-block;
  background: rgba(29, 191, 115, 0.12);
  color: var(--success);
  padding: 8px 12px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
}

.date {
  color: var(--muted);
  font-size: 0.8rem;
}

.hero-card h2 {
  margin: 0 0 20px;
  font-size: 2rem;
  color: var(--navy);
}

.feature-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 12px;
}

.feature-list li {
  position: relative;
  padding-left: 28px;
  color: var(--text);
  line-height: 1.6;
}

.feature-list li::before {
  content: '•';
  position: absolute;
  left: 0;
  top: 0;
  font-size: 1.6rem;
  color: var(--primary);
}

.lesson-box {
  margin-top: 26px;
  background: linear-gradient(135deg, rgba(124, 77, 255, 0.08), rgba(103, 215, 255, 0.1));
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 18px 16px;
}

.lesson-box span {
  display: block;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.lesson-box strong {
  display: block;
  margin-top: 8px;
  font-size: 1.25rem;
  color: var(--navy);
}

.section-head {
  margin-bottom: 36px;
}

.section-head.center {
  text-align: center;
}

.section-head h2 {
  margin: 18px 0 0;
  font-size: 2.4rem;
  line-height: 1.2;
  color: var(--navy);
}

.about-grid,
.review-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.info-box,
blockquote {
  background: rgba(255, 255, 255, 0.75);
  border: 1px solid var(--line);
  border-radius: 24px;
  padding: 24px 20px;
  box-shadow: 0 18px 32px rgba(31, 42, 96, 0.04);
}

.icon-box {
  width: 52px;
  height: 52px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, rgba(124, 77, 255, 0.12), rgba(103, 215, 255, 0.18));
  color: var(--primary-dark);
  font-size: 1.4rem;
  font-weight: 800;
  margin-bottom: 18px;
}

.info-box h3,
.step-item h3 {
  margin: 0 0 12px;
  color: var(--navy);
  font-size: 1.35rem;
}

.info-box p,
.method-copy p,
.step-item p,
blockquote {
  color: var(--muted);
  line-height: 1.8;
}

.method-wrap {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 30px;
  align-items: center;
}

.method-copy h2 {
  margin: 16px 0 12px;
  color: var(--navy);
  font-size: 2.4rem;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.step-item {
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid var(--line);
  border-radius: 22px;
  padding: 20px 18px;
}

.step-item span {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 800;
  color: var(--primary-dark);
  background: rgba(124, 77, 255, 0.08);
  padding: 7px 10px;
  border-radius: 10px;
}

.review-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

blockquote {
  margin: 0;
  font-style: normal;
}

.grades-page,
.units-page {
  padding: 60px 0 90px;
}

.page-banner {
  margin-bottom: 36px;
}

.page-banner h1 {
  font-size: 3rem;
  color: var(--navy);
  margin: 0 0 12px;
}

.page-banner p {
  margin: 0;
  color: var(--muted);
  font-size: 1.03rem;
}

.grade-grid,
.unit-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.grade-card,
.unit-card {
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid var(--line);
  border-radius: 24px;
  padding: 26px 22px;
  box-shadow: 0 18px 32px rgba(31, 42, 96, 0.04);
}

.grade-card .grade-tag,
.unit-card .unit-tag {
  display: inline-block;
  background: rgba(124, 77, 255, 0.08);
  color: var(--primary-dark);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  padding: 8px 12px;
  border-radius: 999px;
  text-transform: uppercase;
}

.grade-card h2,
.unit-card h3 {
  margin: 18px 0 12px;
  color: var(--navy);
  font-size: 1.8rem;
}

.grade-card p,
.unit-card p {
  margin: 0 0 18px;
  color: var(--muted);
  line-height: 1.7;
}

.grade-card .card-btn,
.unit-card .card-btn {
  width: 100%;
  margin-top: 10px;
}

.unit-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.unit-card.today {
  border: 2px solid rgba(124, 77, 255, 0.18);
  background: linear-gradient(135deg, rgba(124, 77, 255, 0.06), rgba(103, 215, 255, 0.08));
}

.unit-card.today .unit-tag {
  background: rgba(255, 182, 72, 0.12);
  color: #b76a00;
}

.unit-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 18px;
  color: var(--muted);
  font-size: 0.82rem;
}

.unit-meta strong {
  color: var(--navy);
}

.page-actions {
  display: flex;
  justify-content: flex-start;
  margin-top: 26px;
}

.unit-lesson-page {
  padding: 52px 0 88px;
}

.unit-lesson-hero {
  padding: 34px 0 42px;
  border-bottom: 1px solid var(--line);
}

.unit-lesson-hero h1 {
  max-width: 760px;
  margin: 18px 0 12px;
  color: var(--navy);
  font-size: 3rem;
  line-height: 1.12;
}

.unit-lesson-hero p,
.lesson-section > p {
  max-width: 760px;
  color: var(--muted);
  line-height: 1.8;
}

.lesson-path {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 24px 0;
}

.lesson-path span {
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.72);
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
}

.lesson-section {
  padding: 38px 0;
  border-bottom: 1px solid var(--line);
}

.lesson-section h2 {
  margin: 0 0 10px;
  color: var(--navy);
  font-size: 1.75rem;
}

.lesson-section h3 {
  margin: 0 0 8px;
  color: var(--navy);
  font-size: 1.12rem;
}

.lesson-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 20px;
}

.lesson-note,
.vocab-item,
.practice-panel {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.78);
}

.vocab-item {
  overflow: hidden;
  padding: 0;
}

.vocab-image {
  aspect-ratio: 16 / 10;
  margin: 0;
  overflow: hidden;
  background: #e9eff2;
}

.vocab-image img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.vocab-image figcaption {
  padding: 5px 14px;
  background: #fff;
  color: var(--muted);
  font-size: 0.7rem;
  line-height: 1.5;
}

.vocab-image figcaption a {
  color: inherit;
}

.vocab-copy {
  padding: 4px 18px 18px;
}

.vocab-copy h3 {
  margin: 12px 0 8px;
  color: var(--navy);
  font-size: 1.12rem;
}

.vocab-copy p {
  margin: 0;
  color: var(--muted);
  line-height: 1.7;
}

.vocab-copy .lesson-example {
  font-size: 0.92rem;
}

.lesson-note p,
.vocab-item p,
.practice-panel p {
  margin: 8px 0 0;
  color: var(--muted);
  line-height: 1.7;
}

.lesson-example {
  display: block;
  margin-top: 12px;
  color: var(--primary-dark);
  font-weight: 700;
}

.trip-form {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 20px;
}

.trip-form label {
  display: grid;
  gap: 7px;
  color: var(--text);
  font-size: 0.9rem;
  font-weight: 700;
}

.trip-form input {
  width: 100%;
  min-height: 46px;
  padding: 10px 12px;
  border: 1px solid rgba(31, 42, 96, 0.2);
  border-radius: 8px;
  background: #fff;
  color: var(--text);
  font: inherit;
}

.trip-form input:focus-visible,
.quiz-next:focus-visible,
.quiz-option:focus-visible {
  outline: 3px solid rgba(31, 111, 178, 0.35);
  outline-offset: 2px;
}

.trip-form button,
.quiz-next {
  min-height: 46px;
  padding: 10px 18px;
  border: 0;
  border-radius: 8px;
  background: var(--primary-dark);
  color: #fff;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

.trip-output {
  margin-top: 16px;
  padding: 16px;
  border-left: 4px solid var(--success);
  background: rgba(29, 191, 115, 0.08);
  line-height: 1.7;
}

.quiz-panel {
  max-width: 760px;
  margin-top: 20px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.85);
}

.quiz-status {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  color: var(--muted);
  font-size: 0.88rem;
}

.quiz-progress {
  height: 7px;
  margin: 12px 0 22px;
  overflow: hidden;
  border-radius: 999px;
  background: rgba(31, 42, 96, 0.1);
}

.quiz-progress span {
  display: block;
  width: 0;
  height: 100%;
  background: var(--success);
  transition: width 180ms ease;
}

.quiz-question {
  min-height: 3.2em;
  margin: 0 0 18px;
  color: var(--navy);
  font-size: 1.2rem;
  font-weight: 700;
}

.quiz-answers {
  display: grid;
  gap: 10px;
}

.quiz-option {
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--text);
  font: inherit;
  text-align: left;
  cursor: pointer;
}

.quiz-option[disabled] {
  cursor: default;
}

.quiz-option.is-correct {
  border-color: var(--success);
  background: rgba(29, 191, 115, 0.1);
}

.quiz-option.is-wrong {
  border-color: #d64e4e;
  background: rgba(214, 78, 78, 0.08);
}

.quiz-feedback {
  min-height: 1.6em;
  margin: 16px 0;
  color: var(--muted);
  line-height: 1.6;
}

.quiz-next:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.lesson-bottom-link {
  margin-top: 28px;
}

@media (max-width: 900px) {
  .hero-grid,
  .method-wrap {
    grid-template-columns: 1fr;
  }

  .about-grid,
  .review-grid,
  .grade-grid,
  .unit-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .main-nav {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
    order: 1;
  }

  .nav-btn {
    order: 2;
  }

  .main-nav.is-open {
    display: flex;
    order: 3;
    flex-basis: 100%;
    flex-wrap: wrap;
    gap: 0;
    padding: 8px 0;
    border-top: 1px solid var(--line);
  }

  .main-nav.is-open a {
    display: flex;
    align-items: center;
    min-height: 44px;
    padding: 0 12px;
  }

  .lesson-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .nav {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 12px;
  }

  .brand-wrap {
    min-width: 0;
  }

  .brand-name {
    font-size: 1rem;
  }

  .nav-toggle {
    grid-column: 2;
    grid-row: 1;
  }

  .nav-btn {
    grid-column: 1 / -1;
    grid-row: 2;
    width: fit-content;
    min-height: 44px;
  }

  .main-nav.is-open {
    grid-column: 1 / -1;
    grid-row: 3;
    flex-direction: column;
    align-items: stretch;
  }

  .hero-copy h1 {
    font-size: 2.25rem;
  }

  .hero-card h2 {
    font-size: 1.65rem;
  }

  .section-head h2,
  .method-copy h2 {
    font-size: 1.9rem;
  }

  .page-banner h1,
  .unit-lesson-hero h1 {
    font-size: 2.2rem;
  }

  .about-grid,
  .review-grid,
  .grade-grid,
  .unit-grid {
    grid-template-columns: 1fr;
  }

  .lesson-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .cta-row,
  .mini-stats,
  .page-actions {
    flex-direction: column;
    align-items: flex-start;
  }

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

  .lesson-grid,
  .trip-form {
    grid-template-columns: 1fr;
  }

  .section-spacing {
    padding: 64px 0;
  }
}