:root {
    --primary: #4F46E5;
    --primary-dark: #4338CA;
    --secondary: #10B981;
    --danger: #EF4444;
    --warning: #F59E0B;
    --bg-primary: #F9FAFB;
    --bg-secondary: #FFFFFF;
    --text-primary: #111827;
    --text-secondary: #6B7280;
    --border: #E5E7EB;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.app-container {
    max-width: 100%;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background: var(--bg-primary);
}

/* Header */
.app-header {
    background: var(--primary);
    color: white;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.app-header h1 {
    font-size: 1.25rem;
    font-weight: 600;
}

.icon-btn {
    background: transparent;
    border: none;
    color: white;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
}

.icon-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}

/* Main Content */
.app-main {
    flex: 1;
    padding: 0;
    padding-bottom: 80px;
    overflow-y: auto;
}

/* Filter Toggle */
.filter-toggle {
    background: white;
    border-bottom: 1px solid var(--border);
    padding: 0.75rem 1rem;
    display: flex;
    justify-content: center;
    display: none; /* Hidden by default, shown via JS */
}

.filter-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    background: var(--bg-primary);
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
}

.filter-btn svg {
    width: 18px;
    height: 18px;
    stroke: currentColor;
}

.filter-btn:hover {
    border-color: var(--primary);
    background: #EEF2FF;
    color: var(--primary);
}

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

.filter-btn.active svg {
    stroke: white;
}

/* Date Scroller */
.date-scroller {
    background: white;
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
    overflow-x: auto;
    overflow-y: hidden;
    white-space: nowrap;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    -ms-overflow-style: none;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    display: none; /* Hidden by default, shown via JS */
}

.date-scroller::-webkit-scrollbar {
    display: none;
}

.date-scroller-inner {
    display: inline-flex;
    gap: 0.75rem;
    padding: 0 1rem;
}

.date-item {
    flex: 0 0 auto;
    min-width: 80px;
    padding: 0.75rem 1rem;
    background: var(--bg-primary);
    border: 2px solid var(--border);
    border-radius: 12px;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
    user-select: none;
    display: inline-block;
}

.date-item:hover {
    border-color: var(--primary);
    background: #EEF2FF;
    transform: translateY(-2px);
}

.date-item.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 6px rgba(79, 70, 229, 0.3);
}

.date-item.active .date-label,
.date-item.active .date-number,
.date-item.active .date-month {
    color: white;
}

.date-label {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
    letter-spacing: 0.5px;
}

.date-number {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1;
    margin: 0.25rem 0;
}

.date-month {
    font-size: 0.625rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
    text-transform: uppercase;
}

/* Classes Grid */
.classes-grid {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    padding: 1rem;
}

.loading-more {
    text-align: center;
    padding: 1.5rem 0;
    color: var(--text-secondary);
    font-style: italic;
}

.no-more-classes {
    text-align: center;
    padding: 1.5rem 0;
    color: var(--text-secondary);
    font-style: italic;
    opacity: 0.7;
}


/* Bottom Navigation */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: space-around;
    padding: 0.5rem 0;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.05);
    z-index: 100;
}

.nav-item {
    background: none;
    border: none;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    padding: 0.5rem 1rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: color 0.2s;
    font-size: 0.75rem;
}

.nav-item svg {
    width: 24px;
    height: 24px;
}

.nav-item.active {
    color: var(--primary);
}

.nav-item:hover {
    color: var(--primary);
}

/* Cards */
.card {
    background: var(--bg-secondary);
    border-radius: 1rem;
    padding: 1.25rem;
    margin-bottom: 1rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}

.class-card {
    position: relative;
}

.class-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 0.75rem;
}

.class-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.class-cost {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
}

.class-description {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.class-meta {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.meta-item svg {
    width: 16px;
    height: 16px;
    color: var(--text-secondary);
}

.class-availability {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
    padding: 0.5rem;
    background: var(--bg-primary);
    border-radius: 0.5rem;
}

.availability-bar {
    flex: 1;
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
}

.availability-fill {
    height: 100%;
    background: var(--secondary);
    transition: width 0.3s;
}

.availability-fill.full {
    background: var(--danger);
}

.availability-text {
    font-size: 0.875rem;
    font-weight: 600;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    width: 100%;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-secondary {
    background: var(--secondary);
    color: white;
}

.btn-secondary:hover {
    opacity: 0.9;
}

.btn-danger {
    background: var(--danger);
    color: white;
}

.btn-danger:hover {
    opacity: 0.9;
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-group {
    display: flex;
    gap: 0.5rem;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    width: auto;
}

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font-size: 1rem;
    font-family: inherit;
    background: var(--bg-secondary);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* Modals */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    padding: 1rem;
    overflow-y: auto;
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--bg-secondary);
    border-radius: 1rem;
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    animation: modalSlideIn 0.3s ease-out;
}

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

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    font-size: 2rem;
    line-height: 1;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-body {
    padding: 1.5rem;
}

.modal-content form {
    padding: 1.5rem;
}

.modal-content > p {
    padding: 1.5rem;
}

/* Badges */
.badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 1rem;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-success {
    background: #D1FAE5;
    color: #065F46;
}

.badge-warning {
    background: #FEF3C7;
    color: #92400E;
}

.badge-danger {
    background: #FEE2E2;
    color: #991B1B;
}

.badge-info {
    background: #DBEAFE;
    color: #1E40AF;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-secondary);
}

.empty-state svg {
    width: 64px;
    height: 64px;
    margin-bottom: 1rem;
    opacity: 0.3;
}

.empty-state h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

/* Loading */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Section Headers */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.section-title {
    font-size: 1.25rem;
    font-weight: 600;
}

/* Admin specific */
.admin-actions {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.user-list-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    margin-bottom: 0.5rem;
}

.user-info h4 {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.user-info p {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.user-icon-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    border: 1px solid var(--border);
    border-radius: 0.375rem;
    background: var(--bg-primary);
    color: var(--text-secondary);
    cursor: pointer;
    text-decoration: none;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.user-icon-btn:hover {
    background: var(--border);
    color: var(--text-primary);
}

.user-icon-btn-danger:hover {
    background: #fee2e2;
    color: var(--danger);
    border-color: var(--danger);
}

.booking-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    border-bottom: 1px solid var(--border);
}

.booking-item:last-child {
    border-bottom: none;
}

/* Utilities */
.text-center {
    text-align: center;
}

.text-small {
    font-size: 0.875rem;
}

.text-muted {
    color: var(--text-secondary);
}

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }

.recipients-list {
    background: var(--bg-primary);
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
}

.recipients-list p {
    margin-bottom: 0.5rem;
}

/* Responsive */
@media (min-width: 768px) {
    .app-container {
        max-width: 768px;
        margin: 0 auto;
        box-shadow: var(--shadow-lg);
    }
    
    .app-main {
        padding: 1.5rem;
    }
}

/* Animations */
.fade-in {
    animation: fadeIn 0.3s ease-in;
}

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

/* Business Info Banner */
.business-info-banner {
    background: linear-gradient(135deg, var(--primary) 0%, #764ba2 100%);
    color: white;
    padding: 2rem 1rem;
    text-align: center;
}

.business-info-content {
    max-width: 600px;
    margin: 0 auto;
}

.business-name {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: white;
}

.business-description {
    font-size: 1rem;
    line-height: 1.6;
    margin-bottom: 1rem;
    opacity: 0.95;
}

.business-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.business-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.1);
    transition: all 0.2s;
    font-size: 0.875rem;
}

.business-link:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.business-link svg {
    width: 20px;
    height: 20px;
}