/* General Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background-color: #121212; /* Dark background */
  color: #e0e0e0; /* Light text for contrast */
  line-height: 1.6;
  padding: 20px;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Header Styles */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0;
  border-bottom: 2px solid #37474f;
  margin-bottom: 2rem;
}

.header-left .title {
  font-size: 2rem;
  color: #80cbc4; /* Teal accent color */
}

.header-left .title i {
  margin-right: 0.5rem;
}

.header-right .back-home-btn {
  background-color: #26a69a; /* Teal button */
  color: #fff;
  padding: 0.75rem 1.25rem;
  text-decoration: none;
  border-radius: 6px;
  font-weight: 500;
  transition: background-color 0.3s ease;
}

.header-right .back-home-btn:hover {
  background-color: #00796b;
}

.header-right .back-home-btn i {
  margin-right: 0.3rem;
}

/* Intro Section */
.intro {
  text-align: center;
  margin-bottom: 2rem;
  padding: 1rem;
  background-color: #1e272e;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.intro p {
  font-size: 1.1rem;
  color: #b2bec3;
}

/* Formula Categories */
.formula-categories {
  margin-bottom: 3rem;
}

.formula-categories h2 {
  font-size: 1.6rem;
  color: #80cbc4;
  margin-bottom: 1rem;
}

.formula-categories h2 i {
  margin-right: 0.5rem;
}

.formula-categories ul {
  list-style: none;
  display: flex;
  justify-content: center;
  gap: 2rem;
  padding: 1rem;
  background-color: #1e272e;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  flex-wrap: wrap;
}

.formula-categories ul li a {
  color: #80cbc4;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease, transform 0.3s ease;
  display: inline-block;
  padding: 0.5rem 1rem;
  border-radius: 4px;
}

.formula-categories ul li a:hover {
  color: #fff;
  transform: translateY(-2px);
}

.formula-categories ul li a i {
  margin-right: 0.3rem;
}

/* Main Content Container */
.formulas-container {
  max-width: 1200px;
  margin: 0 auto;
}

/* Category Sections */
.category-section {
  margin-bottom: 3rem;
}

.category-section h2 {
  font-size: 1.8rem;
  color: #80cbc4;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Formula Card */
.formula-card {
  background-color: #263238;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  margin-bottom: 1.5rem;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.formula-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.3);
}

.formula-card h3 {
  font-size: 1.4rem;
  color: #fff;
  margin-bottom: 0.75rem;
}

.formula-card p {
  font-size: 1.1rem;
  color: #b2bec3;
  margin-bottom: 1rem;
  line-height: 1.4;
}

.formula-card .formula-description {
  font-style: italic;
  color: #607d8b;
}

.formula-card .details-link {
  color: #4db6ac;
  text-decoration: none;
  font-weight: 600;
  transition: color 0.3s ease, border-bottom 0.3s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

.formula-card .details-link:hover {
  color: #fff;
}

/* Footer Styles */
.footer {
  text-align: center;
  padding: 1rem 0;
  border-top: 2px solid #37474f;
  margin-top: 4rem;
  color: #607d8b;
}

/* Media Queries for Responsiveness */
@media (max-width: 768px) {
  .header {
      flex-direction: column;
      text-align: center;
  }

  .header-left {
      margin-bottom: 1rem;
  }

  .formula-categories ul {
      flex-direction: column;
      align-items: center;
  }

  .formula-categories ul li {
      margin-bottom: 0.5rem;
  }
}