body {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 2rem 0;
}

.calculator-card {
    background: white;
    border-radius: 20px;
    padding: 2.5rem;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    margin-top: 2rem;
}

.hero-heading {
    font-weight: 700;
    color: #667eea;
    margin-bottom: 0.5rem;
}

.form-label {
    font-weight: 600;
    color: #555;
}

.form-control {
    border-radius: 10px;
    padding: 0.75rem 1rem;
    border: 2px solid #e0e0e0;
    transition: all 0.3s ease;
}

.form-control:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 0.2rem rgba(102, 126, 234, 0.25);
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 10px;
    padding: 0.75rem;
    font-weight: 600;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.4);
    background: linear-gradient(135deg, #764ba2 0%, #667eea 100%);
}

.btn-outline-secondary {
    border-radius: 10px;
    padding: 0.75rem;
    font-weight: 600;
    border-color: #e0e0e0;
    color: #666;
    transition: all 0.3s ease;
}

.btn-outline-secondary:hover {
    border-color: #667eea;
    color: #667eea;
    background-color: rgba(102, 126, 234, 0.1);
}

.result-card {
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8eb 100%);
    border-radius: 15px;
    padding: 1.5rem;
    text-align: center;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-card .card-title {
    font-weight: 600;
    color: #555;
    margin-bottom: 1rem;
}

.bmi-value {
    font-size: 3rem;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 0.5rem;
}

.health-badge .badge {
    font-size: 1.1rem;
    padding: 0.5rem 1.5rem;
    border-radius: 25px;
    font-weight: 600;
}

.health-message {
    margin-top: 1rem;
    color: #666;
    font-size: 0.95rem;
}

/* Health category colors */
.badge-underweight {
    background-color: #ffc107;
    color: #000;
}

.badge-normal {
    background-color: #28a745;
    color: #fff;
}

.badge-overweight {
    background-color: #fd7e14;
    color: #fff;
}

.badge-obese {
    background-color: #dc3545;
    color: #fff;
}

@media (max-width: 576px) {
    .calculator-card {
        padding: 1.5rem;
        margin: 1rem;
    }
    
    .hero-heading {
        font-size: 1.75rem;
    }
    
    .bmi-value {
        font-size: 2.5rem;
    }
}