* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background: #f5f5f5;
  color: #333;
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

header {
  margin-bottom: 30px;
}

header h1 {
  font-size: 2rem;
  color: rgb(6, 49, 116); /* Deep navy from main site */
  margin-bottom: 5px;
}

header p {
  color: #666;
  font-size: 1.1rem;
}

.back-link {
  display: inline-block;
  color: #666;
  text-decoration: none;
  margin-bottom: 20px;
  font-size: 1.1rem;
  transition: color 0.3s ease;
}

.back-link:hover {
  color: rgb(226, 114, 91); /* Warm peachy accent */
}

/* Week List Grid */
.weeks-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 20px;
  margin-top: 20px;
}

.week-card {
  background: white;
  border-radius: 12px;
  padding: 20px;
  cursor: pointer;
  transition: all 0.3s ease;
  border: 2px solid transparent;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.week-card:hover {
  border-color: rgb(226, 114, 91);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(226, 114, 91, 0.2);
}

.week-number {
  color: rgb(6, 49, 116); /* Navy */
  font-weight: bold;
  font-size: 0.9rem;
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.week-card h3 {
  font-size: 1.2rem;
  margin-bottom: 8px;
  color: #333;
}

.week-card p {
  font-size: 0.9rem;
  color: #666;
  line-height: 1.5;
}

/* Week Detail Page */
.week-header {
  background: linear-gradient(135deg, rgb(6, 49, 116), rgb(131, 152, 186));
  color: white;
  padding: 40px;
  border-radius: 16px;
  margin-bottom: 30px;
  box-shadow: 0 4px 12px rgba(6, 49, 116, 0.2);
}

.week-header h1 {
  font-size: 1.5rem;
  margin-bottom: 10px;
  color: white;
  font-weight: 600;
}

.week-header h2 {
  font-size: 2rem;
  margin-bottom: 10px;
  font-weight: 700;
}

.subtitle {
  font-size: 1.1rem;
  opacity: 0.9;
}

.week-description {
  background: white;
  padding: 25px;
  border-radius: 12px;
  margin-bottom: 25px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.week-description p {
  line-height: 1.7;
  color: #444;
}

.video-container {
  background: white;
  padding: 20px;
  border-radius: 12px;
  margin-bottom: 25px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.video-container video {
  border-radius: 8px;
  width: 100%;
  max-width: 100%;
}

.insights-section {
  background: white;
  padding: 25px;
  border-radius: 12px;
  margin-bottom: 25px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.insights-section h3 {
  font-size: 1.5rem;
  margin-bottom: 15px;
  color: rgb(6, 49, 116);
  font-weight: 600;
}

.insights-list {
  list-style: none;
  padding: 0;
}

.insights-list li {
  padding: 12px 16px;
  margin-bottom: 8px;
  background: #f9f9f9;
  border-left: 4px solid rgb(140, 224, 210); /* Mint green accent */
  border-radius: 4px;
  transition: all 0.3s ease;
}

.insights-list li:hover {
  background: #f0f0f0;
  transform: translateX(2px);
}

.challenge-card {
  background: linear-gradient(135deg, rgb(226, 114, 91), rgb(240, 140, 120));
  color: white;
  padding: 30px;
  border-radius: 16px;
  margin-bottom: 25px;
  box-shadow: 0 4px 12px rgba(226, 114, 91, 0.3);
}

.challenge-card h3 {
  font-size: 1.5rem;
  margin-bottom: 12px;
  color: white;
  font-weight: 600;
}

.challenge-card p {
  font-size: 1.1rem;
  line-height: 1.6;
  color: white;
}

.loading, .error {
  text-align: center;
  padding: 40px;
  font-size: 1.2rem;
  color: #666;
}

.error {
  color: #d32f2f;
  background: #ffebee;
  border-radius: 8px;
  padding: 20px;
  margin: 20px 0;
}

/* Mobile responsive */
@media (max-width: 768px) {
  .weeks-grid {
    grid-template-columns: 1fr;
  }

  .week-header {
    padding: 25px;
  }

  .week-header h1 {
    font-size: 1.2rem;
  }

  .week-header h2 {
    font-size: 1.5rem;
  }

  .container {
    padding: 15px;
  }

  .insights-section,
  .week-description,
  .challenge-card {
    padding: 20px;
  }
}

/* Smooth animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.week-card {
  animation: fadeIn 0.4s ease-out;
}