html, body {
    height: 100%;
  }
  body {
    display: flex;
    flex-direction: column;
  }
  main {
    flex: 3;
  }
  
    .gradient-bg {
        background: linear-gradient(135deg, #1e3a8a 0%, #1e40af 100%);
    }
    .question-card {
        transition: all 0.3s ease;
    }
    .question-card:hover {
        transform: translateY(-5px);
        box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    }
    .option-item {
        transition: all 0.2s ease;
    }
    .option-item:hover {
        background-color: #f0f4ff;
    }
    .option-item.selected {
        background-color: #3b82f6;
        color: white;
    }
    .option-item.correct {
        background-color: #10b981;
        color: white;
    }
    .option-item.incorrect {
        background-color: #ef4444;
        color: white;
    }
    .progress-bar {
        transition: width 0.5s ease;
    }
    .fade-in {
        animation: fadeIn 0.5s ease-in;
    }
    @keyframes fadeIn {
        from {
        opacity: 0;
        }
        to {
        opacity: 1;
        }
    }