/* Material Design Variables */
:root {
    /* Primary Colors */
    --primary-color: #2196F3;
    --primary-light: #64B5F6;
    --primary-dark: #1976D2;
    
    /* Category Colors */
    --importante-color: #F44336;
    --importante-light: #FFEBEE;
    --bonus-color: #2196F3;
    --bonus-light: #E3F2FD;
    --detente-color: #4CAF50;
    --detente-light: #E8F5E8;
    
    /* Surface Colors */
    --surface: #FFFFFF;
    --background: #FAFAFA;
    --surface-variant: #F5F5F5;
    --outline: #E0E0E0;
    
    /* Text Colors */
    --on-surface: #212121;
    --on-surface-variant: #757575;
    --on-primary: #FFFFFF;
    
    /* State Colors */
    --success: #4CAF50;
    --warning: #FF9800;
    --error: #F44336;
    --info: #2196F3;
    
    /* Shadows */
    --shadow-1: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
    --shadow-2: 0 3px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23);
    --shadow-3: 0 10px 20px rgba(0,0,0,0.19), 0 6px 6px rgba(0,0,0,0.23);
    --shadow-4: 0 14px 28px rgba(0,0,0,0.25), 0 10px 10px rgba(0,0,0,0.22);
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    /* Typography */
    --font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 12px;
    --font-size-sm: 14px;
    --font-size-md: 16px;
    --font-size-lg: 18px;
    --font-size-xl: 20px;
    --font-size-xxl: 24px;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Theme */
@media (prefers-color-scheme: dark) {
    :root {
        --surface: #121212;
        --background: #000000;
        --surface-variant: #1E1E1E;
        --outline: #333333;
        --on-surface: #FFFFFF;
        --on-surface-variant: #CCCCCC;
    }
}

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

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-md);
    line-height: 1.5;
    color: var(--on-surface);
    background-color: var(--background);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* App Bar */
.app-bar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: var(--primary-color);
    color: var(--on-primary);
    box-shadow: var(--shadow-2);
    transition: transform var(--transition-normal);
}

.app-bar-content {
    display: flex;
    align-items: center;
    height: 56px;
    padding: 0 var(--spacing-md);
}

.menu-button,
.search-button {
    background: none;
    border: none;
    color: var(--on-primary);
    padding: var(--spacing-sm);
    border-radius: 50%;
    cursor: pointer;
    transition: background-color var(--transition-fast);
    touch-action: manipulation;
}

.menu-button:hover,
.search-button:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.menu-button:active,
.search-button:active {
    background-color: rgba(255, 255, 255, 0.2);
}

.app-title {
    flex: 1;
    font-size: var(--font-size-xl);
    font-weight: 500;
    margin-left: var(--spacing-md);
    margin-right: var(--spacing-md);
}

/* Search Bar */
.search-bar {
    height: 0;
    overflow: hidden;
    transition: height var(--transition-normal);
    background-color: var(--primary-dark);
}

.search-bar.active {
    height: 56px;
}

.search-input-container {
    display: flex;
    align-items: center;
    height: 56px;
    padding: 0 var(--spacing-md);
    gap: var(--spacing-sm);
}

.search-input-container .material-icons {
    color: var(--on-primary);
    opacity: 0.7;
}

#searchInput {
    flex: 1;
    background: none;
    border: none;
    color: var(--on-primary);
    font-size: var(--font-size-md);
    outline: none;
}

#searchInput::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.clear-search {
    background: none;
    border: none;
    color: var(--on-primary);
    padding: var(--spacing-xs);
    border-radius: 50%;
    cursor: pointer;
    opacity: 0.7;
    transition: opacity var(--transition-fast);
}

.clear-search:hover {
    opacity: 1;
}

/* Navigation Drawer */
.nav-drawer {
    position: fixed;
    top: 0;
    left: -280px;
    width: 280px;
    height: 100vh;
    background-color: var(--surface);
    box-shadow: var(--shadow-3);
    z-index: 1100;
    transition: transform var(--transition-normal);
    overflow-y: auto;
}

.nav-drawer.open {
    transform: translateX(280px);
}

.nav-header {
    padding: var(--spacing-lg) var(--spacing-md);
    background-color: var(--primary-color);
    color: var(--on-primary);
}

.nav-header h2 {
    font-size: var(--font-size-lg);
    font-weight: 500;
}

.nav-list {
    list-style: none;
    padding: var(--spacing-sm) 0;
}

.nav-item {
    display: flex;
    align-items: center;
    padding: var(--spacing-md);
    cursor: pointer;
    transition: background-color var(--transition-fast);
    gap: var(--spacing-md);
    touch-action: manipulation;
}

.nav-item:hover {
    background-color: var(--surface-variant);
}

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

.nav-item .material-icons {
    font-size: 24px;
}

.nav-item span:first-of-type {
    flex: 1;
    font-weight: 500;
}

.task-count {
    background-color: var(--outline);
    color: var(--on-surface-variant);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: var(--font-size-xs);
    font-weight: 500;
    min-width: 20px;
    text-align: center;
}

.nav-item.active .task-count {
    background-color: rgba(255, 255, 255, 0.2);
    color: var(--on-primary);
}

.nav-divider {
    height: 1px;
    background-color: var(--outline);
    margin: var(--spacing-sm) var(--spacing-md);
}

/* Overlay */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1050;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.overlay.active {
    opacity: 1;
    visibility: visible;
}

/* Main Content */
.main-content {
    margin-top: 56px;
    padding: var(--spacing-md);
    min-height: calc(100vh - 56px);
    padding-bottom: 88px; /* Space for FAB */
}

/* Filter and Sort Bar */
.filter-sort-bar {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.filter-sort-bar::-webkit-scrollbar {
    display: none;
}

.filter-chips {
    display: flex;
    gap: var(--spacing-sm);
    flex: 1;
}

.chip {
    background-color: var(--surface-variant);
    color: var(--on-surface-variant);
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-sm);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    touch-action: manipulation;
}

.chip:hover {
    background-color: var(--outline);
}

.chip.active {
    background-color: var(--primary-color);
    color: var(--on-primary);
}

.sort-button {
    background-color: var(--surface);
    border: 1px solid var(--outline);
    color: var(--on-surface);
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    touch-action: manipulation;
}

.sort-button:hover {
    background-color: var(--surface-variant);
}

/* Sort Menu */
.sort-menu {
    position: absolute;
    top: 100%;
    right: var(--spacing-md);
    background-color: var(--surface);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-3);
    z-index: 100;
    min-width: 200px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all var(--transition-normal);
}

.sort-menu.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.sort-option {
    display: block;
    width: 100%;
    background: none;
    border: none;
    padding: var(--spacing-md);
    text-align: left;
    cursor: pointer;
    transition: background-color var(--transition-fast);
    font-size: var(--font-size-md);
    color: var(--on-surface);
}

.sort-option:hover {
    background-color: var(--surface-variant);
}

.sort-option.active {
    background-color: var(--primary-light);
    color: var(--on-primary);
    font-weight: 500;
}

.sort-option:first-child {
    border-radius: var(--radius-md) var(--radius-md) 0 0;
}

.sort-option:last-child {
    border-radius: 0 0 var(--radius-md) var(--radius-md);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: var(--spacing-xl) var(--spacing-md);
    color: var(--on-surface-variant);
}

.empty-state .material-icons {
    font-size: 64px;
    margin-bottom: var(--spacing-md);
    opacity: 0.5;
}

.empty-state h3 {
    font-size: var(--font-size-xl);
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
}

.empty-state p {
    font-size: var(--font-size-md);
}

/* Tasks Container */
.tasks-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

/* Category Groups */
.category-group {
    margin-bottom: var(--spacing-xl);
}

.category-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--surface-variant);
    border-radius: var(--radius-md);
}

.category-title {
    font-size: var(--font-size-lg);
    font-weight: 500;
    margin: 0;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.category-title.importante {
    color: var(--importante-color);
}

.category-title.bonus {
    color: var(--bonus-color);
}

.category-title.detente {
    color: var(--detente-color);
}

.category-count {
    background-color: var(--outline);
    color: var(--on-surface-variant);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: var(--font-size-xs);
    font-weight: 500;
    min-width: 20px;
    text-align: center;
}

.category-tasks {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

/* Task Card */
.task-card {
    background-color: var(--surface);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-1);
    overflow: hidden;
    transition: all var(--transition-normal);
    position: relative;
    touch-action: pan-y;
}

.task-card:hover {
    box-shadow: var(--shadow-2);
}

.task-card.completed {
    opacity: 0.7;
}

.task-card.overdue {
    border-left: 4px solid var(--error);
}

.task-card.archived {
    opacity: 0.6;
    border-left: 4px solid var(--on-surface-variant);
}

.task-card.archived .task-title {
    color: var(--on-surface-variant);
}

.task-card.swipe-left {
    transform: translateX(-80px);
}

.task-card.swipe-right {
    transform: translateX(80px);
}

.task-content {
    padding: var(--spacing-md);
    display: flex;
    gap: var(--spacing-md);
}

.task-checkbox {
    width: 24px;
    height: 24px;
    border: 2px solid var(--outline);
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    flex-shrink: 0;
    touch-action: manipulation;
}

.task-checkbox:hover {
    border-color: var(--primary-color);
}

.task-checkbox.checked {
    background-color: var(--success);
    border-color: var(--success);
    color: white;
}

.task-info {
    flex: 1;
    min-width: 0;
}

.task-header {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
}

.task-title {
    flex: 1;
    font-size: var(--font-size-md);
    font-weight: 500;
    line-height: 1.4;
    word-wrap: break-word;
}

.task-title.completed {
    text-decoration: line-through;
    opacity: 0.7;
}

.task-category {
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-size: var(--font-size-xs);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    flex-shrink: 0;
}

.task-category.importante {
    background-color: var(--importante-light);
    color: var(--importante-color);
}

.task-category.bonus {
    background-color: var(--bonus-light);
    color: var(--bonus-color);
}

.task-category.detente {
    background-color: var(--detente-light);
    color: var(--detente-color);
}

.task-description {
    font-size: var(--font-size-sm);
    color: var(--on-surface-variant);
    line-height: 1.4;
    margin-bottom: var(--spacing-sm);
    word-wrap: break-word;
}

.task-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    font-size: var(--font-size-xs);
    color: var(--on-surface-variant);
}

.task-due-date {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.task-due-date.overdue {
    color: var(--error);
    font-weight: 500;
}

.task-due-date.today {
    color: var(--warning);
    font-weight: 500;
}

.task-archived {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--on-surface-variant);
    font-style: italic;
}

.task-archived .material-icons {
    font-size: 14px;
}

.task-actions {
    position: absolute;
    top: 0;
    right: -80px;
    height: 100%;
    width: 80px;
    display: flex;
    background-color: var(--error);
    transition: transform var(--transition-normal);
}

.task-actions.left {
    left: -80px;
    right: auto;
    background-color: var(--success);
}

.task-card.archived .task-actions.left {
    background-color: var(--info);
}

.task-action {
    flex: 1;
    background: none;
    border: none;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color var(--transition-fast);
    touch-action: manipulation;
}

.task-action:hover {
    background-color: rgba(0, 0, 0, 0.1);
}

/* New visible action buttons */
.task-actions-visible {
    display: flex;
    gap: var(--spacing-xs);
    margin-left: auto;
    align-items: center;
}

.task-action-btn {
    background: none;
    border: 1px solid var(--outline);
    color: var(--on-surface-variant);
    padding: var(--spacing-xs);
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    touch-action: manipulation;
    width: 32px;
    height: 32px;
}

.task-action-btn:hover {
    background-color: var(--surface-variant);
    border-color: var(--primary-color);
}

.task-action-btn.archive-btn {
    color: var(--success);
    border-color: var(--success);
}

.task-action-btn.archive-btn:hover {
    background-color: var(--detente-light);
    color: var(--success);
}

.task-action-btn.unarchive-btn {
    color: var(--info);
    border-color: var(--info);
}

.task-action-btn.unarchive-btn:hover {
    background-color: var(--bonus-light);
    color: var(--info);
}

.task-action-btn.edit-btn {
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.task-action-btn.edit-btn:hover {
    background-color: var(--primary-light);
    color: var(--on-primary);
}

.task-action-btn.delete-btn {
    color: var(--error);
    border-color: var(--error);
}

.task-action-btn.delete-btn:hover {
    background-color: var(--importante-light);
    color: var(--error);
}

.task-action-btn .material-icons {
    font-size: 18px;
}

/* Floating Action Button */
.fab {
    position: fixed;
    bottom: var(--spacing-md);
    right: var(--spacing-md);
    width: 56px;
    height: 56px;
    background-color: var(--primary-color);
    color: var(--on-primary);
    border: none;
    border-radius: 50%;
    box-shadow: var(--shadow-3);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-normal);
    z-index: 100;
    touch-action: manipulation;
}

.fab:hover {
    box-shadow: var(--shadow-4);
    transform: scale(1.05);
}

.fab:active {
    transform: scale(0.95);
}

.fab .material-icons {
    font-size: 24px;
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

.modal.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background-color: var(--surface);
    border-radius: var(--radius-lg);
    width: 100%;
    max-width: 500px;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: var(--shadow-4);
    transform: scale(0.9);
    transition: transform var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.modal.active .modal-content {
    transform: scale(1);
}

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

.modal-header h2 {
    font-size: var(--font-size-xl);
    font-weight: 500;
}

.close-button {
    background: none;
    border: none;
    color: var(--on-surface-variant);
    padding: var(--spacing-sm);
    border-radius: 50%;
    cursor: pointer;
    transition: background-color var(--transition-fast);
    touch-action: manipulation;
}

.close-button:hover {
    background-color: var(--surface-variant);
}

/* Form Styles */
.task-form {
    padding: var(--spacing-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--on-surface);
    margin-bottom: var(--spacing-sm);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--outline);
    border-radius: var(--radius-md);
    font-size: var(--font-size-md);
    font-family: var(--font-family);
    background-color: var(--surface);
    color: var(--on-surface);
    transition: border-color var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    resize: vertical;
    min-height: 80px;
}

.form-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
    margin-top: auto;
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--outline);
    background-color: var(--surface);
    position: sticky;
    bottom: 0;
}

/* Buttons */
.btn-primary,
.btn-secondary {
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-md);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    touch-action: manipulation;
    min-width: 100px;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    box-shadow: var(--shadow-2);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 1px solid var(--outline);
}

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

/* Dialog */
.dialog {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 2100;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

.dialog.active {
    opacity: 1;
    visibility: visible;
}

.dialog-content {
    background-color: var(--surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    width: 100%;
    max-width: 400px;
    box-shadow: var(--shadow-4);
    transform: scale(0.9);
    transition: transform var(--transition-normal);
}

.dialog.active .dialog-content {
    transform: scale(1);
}

.dialog-content h3 {
    font-size: var(--font-size-lg);
    font-weight: 500;
    margin-bottom: var(--spacing-md);
}

.dialog-content p {
    color: var(--on-surface-variant);
    margin-bottom: var(--spacing-xl);
    line-height: 1.5;
}

.dialog-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    bottom: var(--spacing-md);
    left: var(--spacing-md);
    right: var(--spacing-md);
    z-index: 3000;
    pointer-events: none;
}

.toast {
    background-color: var(--on-surface);
    color: var(--surface);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-sm);
    box-shadow: var(--shadow-3);
    transform: translateY(100px);
    opacity: 0;
    transition: all var(--transition-normal);
    pointer-events: auto;
}

.toast.show {
    transform: translateY(0);
    opacity: 1;
}

.toast.success {
    background-color: var(--success);
}

.toast.error {
    background-color: var(--error);
}

.toast.warning {
    background-color: var(--warning);
}

.toast.info {
    background-color: var(--info);
}

/* Responsive Design */
@media (max-width: 480px) {
    .main-content {
        padding: var(--spacing-sm);
    }
    
    .filter-sort-bar {
        margin-bottom: var(--spacing-md);
    }
    
    .modal-content {
        margin: var(--spacing-sm);
        max-height: calc(100vh - 32px);
    }
    
    .task-form {
        padding: var(--spacing-md);
    }
    
    .form-actions {
        flex-direction: column-reverse;
    }
    
    .btn-primary,
    .btn-secondary {
        width: 100%;
    }
}

@media (min-width: 768px) {
    .main-content {
        max-width: 800px;
        margin-left: auto;
        margin-right: auto;
    }
    
    .tasks-container {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
        gap: var(--spacing-md);
    }
}

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

/* Focus styles for keyboard navigation */
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --outline: #000000;
        --surface-variant: #F0F0F0;
    }
}

/* Print styles */
@media print {
    .app-bar,
    .nav-drawer,
    .fab,
    .modal,
    .dialog,
    .toast-container {
        display: none !important;
    }
    
    .main-content {
        margin-top: 0;
        padding: 0;
    }
    
    .task-card {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #ccc;
        margin-bottom: var(--spacing-md);
    }
}