:root {
    --primary-color: #4e73df;
    --success-color: #1cc88a;
    --danger-color: #e74a3b;
    --warning-color: #f6c23e;
    --dark-color: #5a5c69;
    --light-color: #f8f9fc;
    --border-radius: 0.75rem;
    --box-shadow: 0 0.15rem 1.75rem 0 rgba(58, 59, 69, 0.15);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    line-height: 1.6;
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from { 
        opacity: 0;
        transform: translateY(30px);
    }
    to { 
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in {
    animation: fadeIn 0.8s ease-out;
}

.animate-slide-up {
    animation: slideUp 0.6s ease-out;
}

/* Cards */
.card {
    border: none;
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--box-shadow);
}

.card-header {
    border-radius: var(--border-radius) var(--border-radius) 0 0 !important;
    border: none;
}

/* Forms */
.form-control {
    border-radius: 0.5rem;
    border: 2px solid #e3e6f0;
    padding: 0.75rem 1rem;
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(78, 115, 223, 0.25);
}

.form-label {
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 0.5rem;
}

/* Buttons */
.btn {
    border-radius: 0.5rem;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    transition: var(--transition);
    border: none;
}

.btn-lg {
    padding: 1rem 2rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), #2e59d9);
}

.btn-success {
    background: linear-gradient(135deg, var(--success-color), #17a673);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

/* Photo Preview */
.photo-preview-container {
    position: relative;
    display: inline-block;
}

.profile-photo {
    object-fit: cover;
    border: 4px solid white;
    box-shadow: var(--box-shadow);
}

/* Info Cards */
.info-card {
    background: var(--light-color);
    padding: 1rem 1.25rem;
    border-radius: 0.5rem;
    border-left: 4px solid var(--primary-color);
}

/* Navbar */
.navbar-brand {
    font-size: 1.5rem;
}

.navbar-nav .nav-link {
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
    transition: var(--transition);
}

.navbar-nav .nav-link:hover {
    background: rgba(255, 255, 255, 0.1);
}

/* Hero Section */
.hero-section {
    padding: 4rem 0;
}

.display-4 {
    font-weight: 700;
    background: linear-gradient(135deg, #fff, #e3e6f0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }
    
    .card-body {
        padding: 1.5rem;
    }
    
    .hero-section {
        padding: 2rem 0;
    }
    
    .display-4 {
        font-size: 2.5rem;
    }
}

/* Loading States */
.spinner-border-sm {
    width: 1rem;
    height: 1rem;
}

/* Validation States */
.was-validated .form-control:valid,
.form-control.is-valid {
    border-color: var(--success-color);
}

.was-validated .form-control:invalid,
.form-control.is-invalid {
    border-color: var(--danger-color);
}

/* Alert Improvements */
.alert {
    border: none;
    border-radius: 0.5rem;
    border-left: 4px solid;
}

.alert-danger {
    background: rgba(231, 74, 59, 0.1);
    border-left-color: var(--danger-color);
    color: #721c24;
}