:root {
    --primary-color: #333;
    --secondary-color: #666;
    --accent-color: #999;
    --light-color: #fff;
    --dark-color: #000;
}

body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    color: var(--primary-color);
}

/* Hero Section */
.hero-section {
    background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('../images/hero-bg.jpg');
    background-size: cover;
    background-position: center;
    color: var(--light-color);
    padding: 100px 0;
}

/* Cards */
.card {
    border: none;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

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

/* Scheduling Grid */
.scheduling-container {
    overflow-x: auto;
    padding: 20px 0;
}

.scheduling-grid {
    display: grid;
    grid-template-columns: 100px repeat(auto-fit, minmax(150px, 1fr));
    gap: 2px;
    background-color: var(--secondary-color);
    padding: 2px;
    min-width: 800px;
}

.time-slot {
    background-color: var(--light-color);
    padding: 10px;
    text-align: center;
    min-height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.time-header {
    background-color: var(--primary-color);
    color: var(--light-color);
    padding: 15px;
    text-align: center;
    font-weight: bold;
}

.time-label {
    background-color: var(--primary-color);
    color: var(--light-color);
    padding: 10px;
    text-align: right;
}

.time-slot:hover {
    background-color: var(--accent-color);
    color: var(--light-color);
}

.time-slot.occupied {
    background-color: var(--secondary-color);
    color: var(--light-color);
    cursor: not-allowed;
}

.time-slot.pending {
    background-color: #ffd700;
    color: var(--dark-color);
    cursor: not-allowed;
}

/* Modal */
.modal-content {
    border-radius: 10px;
    border: none;
}

.modal-header {
    background-color: var(--primary-color);
    color: var(--light-color);
    border-radius: 10px 10px 0 0;
}

.btn-close {
    filter: brightness(0) invert(1);
}

/* Login Modal Styles */
.nav-tabs .nav-link {
    color: var(--secondary-color);
    border: none;
    border-bottom: 2px solid transparent;
}

.nav-tabs .nav-link.active {
    color: var(--primary-color);
    background-color: transparent;
    border-bottom: 2px solid var(--primary-color);
}

.nav-tabs .nav-link:hover {
    border-bottom: 2px solid var(--accent-color);
}

/* User Dropdown */
.dropdown-menu {
    border: none;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.dropdown-item {
    padding: 10px 20px;
    transition: background-color 0.3s ease;
}

.dropdown-item:hover {
    background-color: var(--primary-color);
    color: var(--light-color);
}

.dropdown-item i {
    margin-right: 8px;
    width: 16px;
}

/* Scheduling Grid Improvements */
.scheduling-row {
    display: contents;
}

.time-cell {
    background-color: var(--primary-color);
    color: var(--light-color);
    padding: 10px;
    text-align: center;
    font-weight: bold;
    display: flex;
    align-items: center;
    justify-content: center;
}

.time-slot.disabled {
    background-color: #f8f9fa !important;
    color: #6c757d !important;
    cursor: not-allowed !important;
    font-size: 0.8em;
}

.time-slot.available {
    background-color: var(--light-color);
    border: 1px solid #dee2e6;
    transition: all 0.3s ease;
}

.time-slot.available:hover {
    background-color: #e9ecef;
    transform: scale(1.02);
}

/* Form Improvements */
.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(51, 51, 51, 0.25);
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-primary:hover {
    background-color: var(--secondary-color);
    border-color: var(--secondary-color);
}

/* Alert Improvements */
.alert-info {
    background-color: #e7f3ff;
    border-color: #b3d9ff;
    color: #0c5460;
}

/* Loading State */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    border: 2px solid #f3f3f3;
    border-top: 2px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .hero-section {
        padding: 50px 0;
    }

    .scheduling-grid {
        grid-template-columns: 80px repeat(auto-fit, minmax(120px, 1fr));
    }

    .time-slot {
        padding: 8px;
        font-size: 0.9em;
    }
    
    .btn-outline-light {
        font-size: 0.9em;
        padding: 0.375rem 0.75rem;
    }
    
    .dropdown-menu {
        min-width: 200px;
    }
}