/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Light Theme */
    --primary-color: #4f46e5;
    --primary-dark: #3730a3;
    --secondary-color: #06b6d4;
    --accent-color: #f59e0b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    
    --bg-color: #ffffff;
    --surface-color: #f8fafc;
    --card-color: #ffffff;
    --text-color: #1f2937;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-heavy: 0 10px 25px rgba(0, 0, 0, 0.15);
    
    --border-radius: 12px;
    --border-radius-sm: 8px;
    --transition: all 0.3s ease;
}

[data-theme="dark"] {
    --bg-color: #0f172a;
    --surface-color: #1e293b;
    --card-color: #334155;
    --text-color: #f1f5f9;
    --text-secondary: #cbd5e1;
    --border-color: #475569;
}

body {
    font-family: 'Segoe UI', 'Kalpurush', 'SolaimanLipi', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: var(--transition);
}

/* Loading Screen */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-color);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

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

/* Navigation */
.navbar {
    background: var(--card-color);
    border-bottom: 1px solid var(--border-color);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    box-shadow: var(--shadow-light);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-brand h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
    font-weight: 700;
}

.nav-menu {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius-sm);
    transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
    background: var(--primary-color);
    color: white;
}

.nav-actions {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.theme-toggle, .nav-toggle {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--border-radius-sm);
    transition: var(--transition);
}

.theme-toggle:hover, .nav-toggle:hover {
    background: var(--surface-color);
}

.nav-toggle {
    display: none;
}

/* Main Content */
.main-content {
    margin-top: 70px;
    min-height: calc(100vh - 70px);
    padding: 2rem 1rem;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
}

.page {
    animation: fadeIn 0.5s ease-in-out;
}

.hidden {
    display: none !important;
}

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

/* Hero Section */
.hero {
    text-align: center;
    padding: 3rem 0;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--border-radius);
    margin-bottom: 3rem;
    color: white;
}

.hero-content h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-content p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

/* Search Container */
.search-container {
    display: flex;
    max-width: 500px;
    margin: 0 auto;
    background: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow-medium);
}

.search-input {
    flex: 1;
    border: none;
    padding: 1rem;
    font-size: 1rem;
    color: var(--text-color);
    outline: none;
}

.search-btn {
    background: var(--accent-color);
    border: none;
    padding: 1rem;
    cursor: pointer;
    font-size: 1.2rem;
    transition: var(--transition);
}

.search-btn:hover {
    background: #d97706;
}

/* Page Headers */
.page-header {
    text-align: center;
    margin-bottom: 3rem;
}

.page-header h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.page-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.back-btn {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    margin-bottom: 1rem;
    transition: var(--transition);
}

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

/* Grid Layouts */
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.message-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
}

/* Category Cards */
.category-card {
    background: var(--card-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow-light);
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-heavy);
    border-color: var(--primary-color);
}

.category-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.category-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.category-card p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.category-count {
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
}

/* Message Cards */
.message-card {
    background: var(--card-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-light);
    transition: var(--transition);
    position: relative;
}

.message-card:hover {
    box-shadow: var(--shadow-medium);
    transform: translateY(-2px);
}

.message-text {
    font-size: 1.1rem;
    line-height: 1.7;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.message-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.message-actions {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.action-btn {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

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

.copy-btn:hover {
    background: var(--success-color);
}

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

.favorite-btn {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
}

.favorite-btn.active {
    color: var(--danger-color);
}

/* Admin Styles */
.admin-login {
    max-width: 400px;
    margin: 2rem auto;
}

.login-form {
    background: var(--card-color);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-medium);
}

.login-form h2 {
    text-align: center;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.login-form input {
    width: 100%;
    padding: 0.75rem;
    margin-bottom: 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    font-size: 1rem;
    background: var(--bg-color);
    color: var(--text-color);
}

.login-form button {
    width: 100%;
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem;
    border-radius: var(--border-radius-sm);
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
}

.login-form button:hover {
    background: var(--primary-dark);
}

.login-hint {
    text-align: center;
    margin-top: 1rem;
    color: var(--text-secondary);
}

.admin-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.admin-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--card-color);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    text-align: center;
    border: 1px solid var(--border-color);
}

.stat-card h3 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.admin-actions {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.admin-btn {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: var(--transition);
}

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

.admin-tables {
    display: grid;
    gap: 2rem;
}

.admin-table-section h3 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

/* Modal Styles */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000;
}

.modal-content {
    background: var(--card-color);
    border-radius: var(--border-radius);
    max-width: 600px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: var(--shadow-heavy);
}

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

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
}

.modal-body {
    padding: 1.5rem;
}

.modal-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
    flex-wrap: wrap;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--success-color);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: var(--border-radius-sm);
    box-shadow: var(--shadow-medium);
    z-index: 3000;
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

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

.empty-state span {
    display: block;
    margin-top: 0.5rem;
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-toggle {
        display: block;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: var(--card-color);
        flex-direction: column;
        justify-content: flex-start;
        padding: 2rem;
        transition: var(--transition);
        border-right: 1px solid var(--border-color);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hero-content h2 {
        font-size: 2rem;
    }
    
    .category-grid {
        grid-template-columns: 1fr;
    }
    
    .message-grid {
        grid-template-columns: 1fr;
    }
    
    .search-container {
        flex-direction: column;
    }
    
    .admin-stats {
        grid-template-columns: 1fr;
    }
    
    .admin-actions {
        flex-direction: column;
    }
    
    .modal-content {
        width: 95%;
        margin: 1rem;
    }
    
    .toast {
        right: 1rem;
        left: 1rem;
        bottom: 1rem;
    }
}

@media (max-width: 480px) {
    .main-content {
        padding: 1rem 0.5rem;
    }
    
    .hero {
        padding: 2rem 1rem;
        margin-bottom: 2rem;
    }
    
    .hero-content h2 {
        font-size: 1.5rem;
    }
    
    .nav-container {
        padding: 0 0.5rem;
    }
    
    .message-actions {
        flex-direction: column;
    }
    
    .action-btn {
        justify-content: center;
    }
}

/* Print Styles */
@media print {
    .navbar,
    .modal,
    .toast,
    .action-btn,
    .favorite-btn {
        display: none !important;
    }
    
    .main-content {
        margin-top: 0;
    }
    
    body {
        background: white;
        color: black;
    }
}

/* High contrast mode */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --text-secondary: #000000;
    }
    
    [data-theme="dark"] {
        --border-color: #ffffff;
        --text-secondary: #ffffff;
    }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}