/**
 * Responsive Design - Mobile First
 * Breakpoints: Mobile (<768px), Tablet (768-1023px), Desktop (1024px+)
 */

/* ===== Display Utilities ===== */
.mobile-only {
    display: block;
}

.desktop-only {
    display: none;
}

@media (min-width: 768px) {
    .mobile-only {
        display: none;
    }
    
    .desktop-only {
        display: block;
    }
}

/* ===== Header & Navigation ===== */
.header {
    background-color: var(--white);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md);
    max-width: var(--max-width);
    margin: 0 auto;
}

.logo {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

/* Mobile Navigation (Hamburger Menu) */
.nav-toggle {
    display: block;
    background: none;
    border: none;
    font-size: 28px;
    cursor: pointer;
    padding: var(--spacing-sm);
    color: var(--text-primary);
}

.nav-menu {
    display: none;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--white);
    padding: var(--spacing-md);
    overflow-y: auto;
    z-index: 99;
}

.nav-menu.show {
    display: block;
}

.nav-menu ul {
    list-style: none;
}

.nav-menu li {
    margin-bottom: var(--spacing-sm);
}

.nav-menu a {
    display: block;
    padding: var(--spacing-md);
    color: var(--text-primary);
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: background-color var(--transition-fast);
}

.nav-menu a:hover,
.nav-menu a.active {
    background-color: var(--light-gray);
    text-decoration: none;
}

/* Bottom Navigation (Mobile) */
.bottom-nav {
    display: flex;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: var(--white);
    border-top: 1px solid var(--border-color);
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    z-index: 100;
}

.bottom-nav a {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm);
    color: var(--text-secondary);
    text-decoration: none;
    font-size: var(--font-size-sm);
    min-height: 60px;
}

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

.bottom-nav-icon {
    font-size: 24px;
    margin-bottom: 4px;
}

/* ===== Main Layout ===== */
.main-wrapper {
    min-height: calc(100vh - var(--header-height) - 60px);
    padding-bottom: 80px; /* Space for bottom nav on mobile */
}

.main-content {
    padding: var(--spacing-md);
}

/* ===== Page Header ===== */
.page-header {
    margin-bottom: var(--spacing-lg);
}

.page-title {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
}

.page-actions {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.page-actions .btn {
    width: 100%;
}

/* ===== Dashboard Cards ===== */
.dashboard-stats {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.stat-card {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--primary-color);
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

.stat-value {
    font-size: var(--font-size-xxl);
    font-weight: 700;
    color: var(--text-primary);
}

/* ===== List Items (Mobile Cards) ===== */
.list-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.list-item {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.list-item-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-sm);
}

.list-item-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin: 0;
}

.list-item-meta {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.list-item-body {
    margin-bottom: var(--spacing-sm);
}

.list-item-footer {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.list-item-footer .btn {
    flex: 1;
    min-width: 100px;
}

/* ===== Filters (Mobile) ===== */
.filters {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-md);
    box-shadow: var(--shadow-sm);
}

.filter-toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    padding: var(--spacing-sm);
    background: none;
    border: none;
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
}

.filter-content {
    display: none;
    padding-top: var(--spacing-md);
}

.filter-content.show {
    display: block;
}

/* ===== File Upload (Mobile) ===== */
.file-upload {
    border: 2px dashed var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.file-upload-icon {
    font-size: 48px;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.file-upload-text {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.file-upload input[type="file"] {
    display: none;
}

.file-preview {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.file-preview-item {
    display: flex;
    align-items: center;
    padding: var(--spacing-sm);
    background-color: var(--light-gray);
    border-radius: var(--border-radius);
}

.file-preview-icon {
    font-size: 24px;
    margin-right: var(--spacing-sm);
}

.file-preview-info {
    flex: 1;
}

.file-preview-name {
    font-weight: 500;
    margin-bottom: 4px;
}

.file-preview-size {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.file-preview-remove {
    background: none;
    border: none;
    color: var(--danger-color);
    font-size: 20px;
    cursor: pointer;
    padding: var(--spacing-sm);
}

/* ===== Camera Capture (Mobile) ===== */
.camera-capture {
    margin-bottom: var(--spacing-md);
}

.camera-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    width: 100%;
    padding: var(--spacing-md);
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: var(--border-radius);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    min-height: 56px;
}

.camera-icon {
    font-size: 24px;
}

/* ===== Tablet Styles (768px - 1023px) ===== */
@media (min-width: 768px) {
    .main-wrapper {
        padding-bottom: 0;
    }
    
    .bottom-nav {
        display: none;
    }
    
    .nav-toggle {
        display: none;
    }
    
    .nav-menu {
        display: flex;
        position: static;
        background: none;
        padding: 0;
    }
    
    .nav-menu ul {
        display: flex;
        gap: var(--spacing-sm);
    }
    
    .nav-menu li {
        margin-bottom: 0;
    }
    
    .nav-menu a {
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .dashboard-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .page-actions {
        flex-direction: row;
        justify-content: flex-end;
    }
    
    .page-actions .btn {
        width: auto;
    }
    
    .file-preview {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .col-md-6 {
        flex: 0 0 50%;
        max-width: 50%;
    }
    
    .col-md-4 {
        flex: 0 0 33.333%;
        max-width: 33.333%;
    }
    
    .col-md-3 {
        flex: 0 0 25%;
        max-width: 25%;
    }
}

/* ===== Desktop Styles (1024px+) ===== */
@media (min-width: 1024px) {
    .main-wrapper {
        display: flex;
    }
    
    .sidebar {
        width: 250px;
        background-color: var(--white);
        border-right: 1px solid var(--border-color);
        min-height: calc(100vh - var(--header-height));
        padding: var(--spacing-md);
    }
    
    .sidebar-nav {
        list-style: none;
    }
    
    .sidebar-nav li {
        margin-bottom: var(--spacing-xs);
    }
    
    .sidebar-nav a {
        display: flex;
        align-items: center;
        padding: var(--spacing-sm) var(--spacing-md);
        color: var(--text-primary);
        text-decoration: none;
        border-radius: var(--border-radius);
        transition: background-color var(--transition-fast);
    }
    
    .sidebar-nav a:hover,
    .sidebar-nav a.active {
        background-color: var(--light-gray);
        text-decoration: none;
    }
    
    .sidebar-nav-icon {
        margin-right: var(--spacing-sm);
        font-size: 20px;
    }
    
    .main-content {
        flex: 1;
        padding: var(--spacing-lg);
    }
    
    .dashboard-stats {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .list-container {
        display: block;
    }
    
    .file-preview {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .col-lg-6 {
        flex: 0 0 50%;
        max-width: 50%;
    }
    
    .col-lg-4 {
        flex: 0 0 33.333%;
        max-width: 33.333%;
    }
    
    .col-lg-3 {
        flex: 0 0 25%;
        max-width: 25%;
    }
    
    .col-lg-2 {
        flex: 0 0 16.666%;
        max-width: 16.666%;
    }
}

/* ===== Large Desktop (1440px+) ===== */
@media (min-width: 1440px) {
    .container {
        max-width: 1400px;
    }
    
    .dashboard-stats {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* ===== Touch Device Optimizations ===== */
@media (hover: none) and (pointer: coarse) {
    /* Increase tap targets for touch devices */
    .btn {
        min-height: 48px;
        padding: 14px 24px;
    }
    
    .form-control {
        min-height: 48px;
        padding: 14px 16px;
    }
    
    .nav-menu a {
        min-height: 48px;
    }
    
    /* Remove hover effects on touch devices */
    .btn:hover {
        transform: none;
    }
}

/* ===== Print Styles ===== */
@media print {
    .header,
    .nav-menu,
    .bottom-nav,
    .sidebar,
    .page-actions,
    .btn,
    .no-print {
        display: none !important;
    }
    
    .main-content {
        padding: 0;
    }
    
    .card {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #000;
    }
}

/* ===== High Contrast Mode ===== */
@media (prefers-contrast: high) {
    .btn {
        border-width: 2px;
    }
    
    .form-control {
        border-width: 2px;
    }
    
    .card {
        border-width: 2px;
    }
}

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

/* ===== Dark Mode Support (Optional) ===== */
@media (prefers-color-scheme: dark) {
    /* Uncomment to enable dark mode */
    /*
    :root {
        --bg-primary: #1a1a1a;
        --bg-secondary: #2d2d2d;
        --text-primary: #ffffff;
        --text-secondary: #b0b0b0;
        --border-color: #404040;
    }
    
    body {
        background-color: var(--bg-secondary);
        color: var(--text-primary);
    }
    
    .card,
    .header,
    .nav-menu {
        background-color: var(--bg-primary);
    }
    */
}