:root {
  --bg: #f8fafc;
  --white: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --border: #e2e8f0;
  --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
  --radius: 20px;

  --green-1: #14b8a6;
  --green-2: #84cc16;

  --orange-1: #f59e0b;
  --orange-2: #f97316;

  --pink-1: #ec4899;
  --pink-2: #f43f5e;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Vazirmatn, IRANSans, Yekan, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.9;
}

a {
  text-decoration: none;
  color: inherit;
}

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

.lesson-page {
  padding: 24px 16px 48px;
}

.container {
  width: min(1100px, 100%);
  margin: 0 auto;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 20px;
}

.breadcrumb a {
  color: #2563eb;
}

.hero-box,
.content-box {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-bottom: 24px;
}

.hero-box h1 {
  margin: 0 0 12px;
  font-size: clamp(28px, 4vw, 40px);
  line-height: 1.4;
}

.hero-box p,
.content-box p {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
}

.content-box h2 {
  margin: 0 0 12px;
  font-size: 24px;
  line-height: 1.6;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 24px;
}

.card-link {
  display: block;
}

.lesson-card {
  min-height: 180px;
  border-radius: var(--radius);
  padding: 24px;
  color: #fff;
  box-shadow: var(--shadow);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.lesson-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 35px rgba(15, 23, 42, 0.14);
}

.lesson-card h2 {
  margin: 0 0 10px;
  font-size: 24px;
  line-height: 1.7;
}

.lesson-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.95);
}

.card-green {
  background: linear-gradient(135deg, var(--green-1), var(--green-2));
}

.card-orange {
  background: linear-gradient(135deg, var(--orange-1), var(--orange-2));
}

.card-pink {
  background: linear-gradient(135deg, var(--pink-1), var(--pink-2));
}

.quick-links {
  list-style: none;
  margin: 0;
  padding: 0;
}

.quick-links li + li {
  margin-top: 10px;
}

.quick-links a {
  color: #2563eb;
  font-weight: 500;
}

.quick-links a:hover {
  text-decoration: underline;
}

@media (max-width: 992px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .lesson-card h2 {
    font-size: 22px;
  }
}

@media (max-width: 768px) {
  .lesson-page {
    padding: 20px 12px 36px;
  }

  .hero-box,
  .content-box,
  .lesson-card {
    padding: 18px;
    border-radius: 16px;
  }

  .card-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .hero-box h1 {
    font-size: 28px;
  }

  .content-box h2,
  .lesson-card h2 {
    font-size: 20px;
  }

  .hero-box p,
  .content-box p,
  .lesson-card p {
    font-size: 15px;
  }
}

@media (max-width: 480px) {
  .breadcrumb {
    font-size: 13px;
  }

  .hero-box h1 {
    font-size: 24px;
  }

  .content-box h2,
  .lesson-card h2 {
    font-size: 18px;
  }
}