/* ------------------------------
   Global Reset & Base
------------------------------ */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #f4f6f9;
  color: #222;
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ------------------------------
   Header
------------------------------ */
.header {
  background: linear-gradient(135deg, #3b82f6, #1e40af);
  color: #fff;
  text-align: center;
  padding: 3rem 1rem;
  box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}

.header h1 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

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

/* ------------------------------
   Subjects Section
------------------------------ */
.main {
  flex: 1;
  padding: 2rem 1rem 4rem;
}

.subjects-section {
  max-width: 1100px;
  margin: 0 auto;
  text-align: center;
}

.subjects-section h2 {
  font-size: 1.8rem;
  color: #1e3a8a;
  margin-bottom: 1.5rem;
}

/* ------------------------------
   Subjects Grid
------------------------------ */
.subjects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1.5rem;
  justify-content: center;
}

.subject-card {
  background: #fff;
  border-radius: 15px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.08);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.subject-card a {
  display: block;
  padding: 1.5rem;
  color: #1e3a8a;
  text-decoration: none;
  font-weight: 600;
  font-size: 1.05rem;
}

.subject-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 15px rgba(0,0,0,0.15);
}

/* ------------------------------
   Footer
------------------------------ */
.footer {
  background: #1e3a8a;
  color: #fff;
  text-align: center;
  padding: 1.2rem;
  font-size: 0.95rem;
  margin-top: auto;
}

.footer p {
  margin: 0;
}

/* ------------------------------
   Responsive Design
------------------------------ */
@media (max-width: 600px) {
  .header h1 {
    font-size: 1.6rem;
  }
  
  .subjects-section h2 {
    font-size: 1.4rem;
  }
  
  .subject-card a {
    font-size: 1rem;
    padding: 1rem;
  }
}