:root {
    --primary-color: #0d6efd;
    --secondary-color: #6c757d;
    --success-color: #198754;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #0dcaf0;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --dental-blue: #2c5aa0;
    --dental-light: #e8f4fd;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f8f9fa;
}

.navbar-brand {
    font-weight: bold;
    font-size: 1.5rem;
}

.hero-section {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--dental-blue) 0%, var(--primary-color) 100%);
    color: white;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-section .card {
    background: white;
    color: var(--dark-color);
    border: none;
    border-radius: 15px;
}

.feature-icon i {
    opacity: 0.8;
}

.btn {
    border-radius: 8px;
    padding: 12px 30px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.demo-login-btn {
    font-weight: 700;
    padding: 16px 30px;
    box-shadow: 0 8px 18px rgba(13, 110, 253, 0.25);
}

.demo-login-panel {
    background-color: var(--dental-light);
    border: 1px solid rgba(13, 110, 253, 0.2);
    border-radius: 8px;
    padding: 18px;
    text-align: center;
}

.demo-login-label {
    color: var(--dental-blue);
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0;
    text-transform: uppercase;
}

.form-control {
    border-radius: 8px;
    padding: 12px 15px;
    border: 1px solid #ddd;
    transition: border-color 0.3s ease;
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(13, 110, 253, 0.25);
}

.card {
    border: none;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border-radius: 10px;
}

.alert {
    border: none;
    border-radius: 8px;
}

.table {
    background: white;
}

.table thead th {
    background-color: var(--dental-light);
    color: var(--dental-blue);
    border: none;
    font-weight: 600;
}

.badge {
    padding: 6px 12px;
    border-radius: 6px;
}

.loading {
    display: none;
    text-align: center;
    padding: 20px;
}

.spinner-border {
    width: 3rem;
    height: 3rem;
}

.appointment-card {
    transition: transform 0.3s ease;
    cursor: pointer;
}

.appointment-card:hover {
    transform: translateY(-5px);
}

.file-upload-area {
    border: 2px dashed #ddd;
    border-radius: 10px;
    padding: 40px 20px;
    text-align: center;
    background-color: #fafafa;
    transition: all 0.3s ease;
    cursor: pointer;
}

.file-upload-area:hover {
    border-color: var(--primary-color);
    background-color: var(--dental-light);
}

.file-upload-area.dragover {
    border-color: var(--success-color);
    background-color: rgba(25, 135, 84, 0.1);
}

.profile-section {
    background: white;
    padding: 30px;
    border-radius: 10px;
    margin-bottom: 30px;
}

.stats-card {
    background: linear-gradient(135deg, var(--primary-color), var(--dental-blue));
    color: white;
    padding: 25px;
    border-radius: 10px;
    text-align: center;
}

.stats-card h3 {
    margin: 0;
    font-size: 2.5rem;
    font-weight: bold;
}

.radiograph-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.radiograph-item {
    background: white;
    border-radius: 10px;
    padding: 15px;
    text-align: center;
    transition: transform 0.3s ease;
}

.radiograph-item:hover {
    transform: scale(1.05);
}

.radiograph-thumbnail {
    width: 100%;
    height: 150px;
    background-color: #f0f0f0;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 10px;
}

@media (max-width: 768px) {
    .hero-section {
        padding: 40px 0;
    }
    
    .feature-icon i {
        font-size: 2rem !important;
    }
    
    .display-4 {
        font-size: 2rem;
    }
}

/* Animation classes */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.slide-in {
    animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateX(-50px); }
    to { opacity: 1; transform: translateX(0); }
}