:root {
  --primary-green: #2e7d32;
  --secondary-green: #4caf50;
  --light-green: #81c784;
  --primary-orange: #ff5722;
  --secondary-orange: #ff9800;
  --light-orange: #ffb74d;
  --white: #ffffff;
  --light-gray: #f5f5f5;
  --dark-gray: #333333;
}

.theory-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
}

.hero-section {
  background: linear-gradient(
    135deg,
    var(--primary-green),
    var(--secondary-green)
  );
  color: var(--white);
  padding: 4rem 2rem;
  text-align: center;
  border-radius: 15px;
  margin-bottom: 3rem;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.hero-content h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  font-weight: 700;
}

.theory-intro {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 0 auto;
  line-height: 1.6;
}

.principles-grid,
.strategy-grid,
.metrics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin: 2rem 0;
}

.principle-item,
.strategy-item,
.metric-item {
  background: var(--white);
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s ease;
}

.principle-item:hover,
.strategy-item:hover,
.metric-item:hover {
  transform: translateY(-5px);
}

.principle-item i,
.metric-item i {
  font-size: 2.5rem;
  color: var(--primary-orange);
  margin-bottom: 1rem;
}

.principle-item h3,
.strategy-item h3,
.metric-item h3 {
  color: var(--primary-green);
  margin-bottom: 1rem;
  font-size: 1.5rem;
}

.principle-item ul,
.strategy-item ul {
  list-style: none;
  padding: 0;
}

.principle-item ul li,
.strategy-item ul li {
  margin: 0.5rem 0;
  padding-left: 1.5rem;
  position: relative;
}

.principle-item ul li:before,
.strategy-item ul li:before {
  content: "•";
  color: var(--secondary-orange);
  position: absolute;
  left: 0;
}

section h2 {
  color: var(--primary-green);
  text-align: center;
  font-size: 2rem;
  margin: 3rem 0 2rem;
  position: relative;
}

section h2:after {
  content: "";
  display: block;
  width: 50px;
  height: 3px;
  background: var(--primary-orange);
  margin: 0.5rem auto;
}

.implementation-approach {
  background: var(--light-gray);
  padding: 3rem 0;
  margin: 3rem 0;
}

.success-metrics {
  background: linear-gradient(135deg, var(--light-green), var(--light-orange));
  padding: 3rem 0;
  margin: 3rem 0;
  border-radius: 15px;
}

.metric-item {
  text-align: center;
}

.metric-item p {
  color: var(--dark-gray);
  font-size: 1.1rem;
}

@media (max-width: 768px) {
  .principles-grid,
  .strategy-grid,
  .metrics-grid {
    grid-template-columns: 1fr;
  }

  .hero-content h1 {
    font-size: 2rem;
  }

  .theory-content {
    padding: 1rem;
  }
}