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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
    line-height: 1.6;
    transition: all 0.3s ease;
    background-color: var(--bg-color);
    color: var(--text-color);
}

/* Layout */
.hidden {
    display: none !important;
}

.header {
    background: var(--header-bg);
    color: var(--header-text);
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 2px 4px var(--shadow-light);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.company-logo {
    height: 40px;
    width: auto;
    object-fit: contain;
    transition: all 0.3s ease;
}

.company-logo:hover {
    transform: scale(1.05);
}

.header h1 {
    font-size: 1.8rem;
    font-weight: 600;
    margin: 0;
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.theme-toggle {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    background: var(--hover-bg);
    transform: rotate(15deg);
}

.user-info {
    font-weight: 500;
    color: var(--text-secondary);
}

.logout-btn {
    background: var(--danger-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.3s ease;
}

.logout-btn:hover {
    background: var(--danger-hover);
    transform: translateY(-1px);
}

/* Navigation Tabs */
.nav-tabs {
    background: var(--nav-bg);
    padding: 0 2rem;
    display: flex;
    gap: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.nav-tab {
    background: none;
    border: none;
    padding: 1rem 1.5rem;
    cursor: pointer;
    font-weight: 500;
    color: var(--text-secondary);
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
}

.nav-tab:hover {
    color: var(--primary-color);
    background: var(--hover-bg);
}

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

/* Tab Content */
.tab-content {
    display: none;
    padding: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.tab-content.active {
    display: block;
}

/* Controls Panel */
.controls-panel {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    gap: 1rem;
    flex-wrap: wrap;
}

.search-filters {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.search-filters input,
.search-filters select {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--input-bg);
    color: var(--text-color);
    font-size: 0.9rem;
    min-width: 150px;
    transition: all 0.3s ease;
}

.search-filters input:focus,
.search-filters select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-color-20);
}

.action-buttons {
    display: flex;
    gap: 0.5rem;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px var(--primary-color-20);
}

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

.btn-secondary:hover {
    background: var(--hover-bg);
    transform: translateY(-1px);
}

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

.btn-danger:hover {
    background: var(--danger-hover);
    transform: translateY(-1px);
}

.btn-full {
    width: 100%;
    justify-content: center;
}

/* Tasks List */
.tasks-list {
    display: grid;
    gap: 1rem;
    margin-bottom: 2rem;
}

.task-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 1px 3px var(--shadow-light);
}

.task-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px var(--shadow-medium);
    border-color: var(--primary-color);
}

.task-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.task-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.task-priority {
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 500;
    text-transform: uppercase;
}

.priority-low {
    background: var(--priority-low-bg);
    color: var(--priority-low-text);
}

.priority-medium {
    background: var(--priority-medium-bg);
    color: var(--priority-medium-text);
}

.priority-high {
    background: var(--priority-high-bg);
    color: var(--priority-high-text);
}

.priority-urgent {
    background: var(--priority-urgent-bg);
    color: var(--priority-urgent-text);
}

.task-description {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-size: 0.9rem;
    line-height: 1.5;
}

.task-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.task-status {
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-weight: 500;
}

.status-new {
    background: var(--status-new-bg);
    color: var(--status-new-text);
}

.status-in_progress {
    background: var(--status-progress-bg);
    color: var(--status-progress-text);
}

.status-completed {
    background: var(--status-completed-bg);
    color: var(--status-completed-text);
}

.status-overdue {
    background: var(--status-overdue-bg);
    color: var(--status-overdue-text);
}

/* Modals */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

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

.modal-content {
    background: var(--modal-bg);
    border-radius: 12px;
    padding: 2rem;
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    transform: translateY(-20px);
    transition: transform 0.3s ease;
    box-shadow: 0 20px 60px var(--shadow-heavy);
}

.modal-content.large {
    max-width: 800px;
}

.modal.active .modal-content {
    transform: translateY(0);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.modal-header h2 {
    color: var(--text-color);
    font-size: 1.5rem;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    padding: 0.5rem;
    border-radius: 50%;
    transition: all 0.3s ease;
}

.modal-close:hover {
    background: var(--hover-bg);
    color: var(--text-color);
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

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

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--input-bg);
    color: var(--text-color);
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-color-20);
}

.form-group small {
    display: block;
    margin-top: 0.25rem;
    color: var(--text-secondary);
    font-size: 0.8rem;
}

.required {
    color: var(--danger-color);
}

.modal-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
    margin-top: 2rem;
}

/* Authentication Pages */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-color);
    padding: 2rem;
}

.auth-card {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 2rem;
    width: 100%;
    max-width: 400px;
    box-shadow: 0 10px 40px var(--shadow-medium);
}

.auth-header {
    text-align: center;
    margin-bottom: 2rem;
}

.auth-brand {
    margin-bottom: 1.5rem;
}

.auth-logo {
    height: 60px;
    width: auto;
    object-fit: contain;
    opacity: 0.9;
    transition: all 0.3s ease;
}

.auth-logo:hover {
    opacity: 1;
    transform: scale(1.02);
}

.auth-header h1 {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.auth-header p {
    color: var(--text-secondary);
}

.auth-form {
    margin-bottom: 1.5rem;
}

.auth-footer {
    text-align: center;
}

.auth-footer a {
    color: var(--primary-color);
    text-decoration: none;
}

.auth-footer a:hover {
    text-decoration: underline;
}

.demo-credentials {
    margin-top: 1.5rem;
    padding: 1rem;
    background: var(--info-bg);
    border-radius: 6px;
    font-size: 0.85rem;
}

.demo-credentials h4 {
    margin-bottom: 0.5rem;
    color: var(--info-text);
}

.demo-credentials p {
    margin-bottom: 0.25rem;
    color: var(--info-text);
}

.theme-toggle-auth {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 10px var(--shadow-light);
}

.theme-toggle-auth:hover {
    transform: rotate(15deg);
    box-shadow: 0 4px 20px var(--shadow-medium);
}

/* Alerts */
.alert {
    padding: 1rem;
    border-radius: 6px;
    margin-bottom: 1rem;
    font-weight: 500;
}

.alert-error {
    background: var(--danger-bg);
    color: var(--danger-text);
    border: 1px solid var(--danger-border);
}

.alert-success {
    background: var(--success-bg);
    color: var(--success-text);
    border: 1px solid var(--success-border);
}

.alert-warning {
    background: var(--warning-bg);
    color: var(--warning-text);
    border: 1px solid var(--warning-border);
}

.alert-info {
    background: var(--info-bg);
    color: var(--info-text);
    border: 1px solid var(--info-border);
}

/* Task Details */
.task-details-content {
    margin-top: 1rem;
}

.task-info {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 2rem;
}

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

.task-details-info h4 {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.task-meta-details {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.meta-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

.meta-item strong {
    color: var(--text-color);
}

.detail-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1rem;
}

.detail-tab {
    background: none;
    border: none;
    padding: 1rem 1.5rem;
    cursor: pointer;
    font-weight: 500;
    color: var(--text-secondary);
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
}

.detail-tab:hover {
    color: var(--primary-color);
    background: var(--hover-bg);
}

.detail-tab.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.detail-content {
    display: none;
}

.detail-content.active {
    display: block;
}

/* Comments */
.comment-form {
    margin-bottom: 2rem;
}

.comment-form textarea {
    margin-bottom: 1rem;
}

.comments-list {
    max-height: 300px;
    overflow-y: auto;
}

.comment-item {
    background: var(--comment-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem;
    margin-bottom: 1rem;
}

.comment-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.comment-author {
    font-weight: 600;
    color: var(--text-color);
}

.comment-text {
    color: var(--text-color);
    line-height: 1.5;
}

/* Files */
.file-upload {
    display: flex;
    gap: 1rem;
    align-items: center;
    margin-bottom: 2rem;
    padding: 1rem;
    background: var(--upload-bg);
    border: 2px dashed var(--border-color);
    border-radius: 8px;
}

.files-list {
    max-height: 300px;
    overflow-y: auto;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background: var(--file-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 0.5rem;
}

.file-info {
    flex: 1;
}

.file-name {
    font-weight: 500;
    color: var(--text-color);
}

.file-date {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Activity */
.activity-list {
    max-height: 400px;
    overflow-y: auto;
}

.activity-item {
    padding: 1rem;
    border-left: 3px solid var(--primary-color);
    background: var(--activity-bg);
    margin-bottom: 1rem;
    border-radius: 0 8px 8px 0;
}

.activity-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.activity-user {
    font-weight: 600;
    color: var(--text-color);
}

.activity-date {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.activity-action {
    color: var(--text-color);
}

/* Reports */
.reports-panel {
    padding: 2rem 0;
}

.reports-filters {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.reports-filters input,
.reports-filters button {
    padding: 0.75rem 1rem;
}

.chart-container {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 2rem;
    margin-bottom: 2rem;
    height: 400px;
}

.performance-table {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.performance-table table {
    width: 100%;
    border-collapse: collapse;
}

.performance-table th,
.performance-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.performance-table th {
    background: var(--table-header-bg);
    font-weight: 600;
    color: var(--text-color);
}

.performance-table td {
    color: var(--text-color);
}

.performance-table tr:hover {
    background: var(--hover-bg);
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0.5rem;
    margin-top: 2rem;
}

.pagination button {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    background: var(--button-bg);
    color: var(--text-color);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.pagination button:hover {
    background: var(--hover-bg);
}

.pagination button.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

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

/* Toast Notifications */
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--success-color);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    box-shadow: 0 4px 20px var(--shadow-heavy);
    transform: translateX(400px);
    transition: transform 0.3s ease;
    z-index: 2000;
    font-weight: 500;
}

.toast.show {
    transform: translateX(0);
}

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

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

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

/* Loading States */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    color: var(--text-secondary);
}

.loading::after {
    content: '';
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    border-top-color: var(--primary-color);
    animation: spin 1s ease-in-out infinite;
    margin-left: 0.5rem;
}

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

/* Empty States */
.no-tasks,
.no-comments,
.no-files,
.no-activity,
.no-data {
    text-align: center;
    padding: 3rem 2rem;
    color: var(--text-secondary);
}

.no-tasks h3 {
    color: var(--text-color);
    margin-bottom: 1rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .header-content {
        padding: 0 1rem;
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }

    .header-controls {
        justify-content: center;
    }

    .nav-tabs {
        padding: 0 1rem;
    }

    .tab-content {
        padding: 1rem;
    }

    .controls-panel {
        flex-direction: column;
        align-items: stretch;
    }

    .search-filters {
        justify-content: stretch;
    }

    .search-filters input,
    .search-filters select {
        min-width: auto;
        flex: 1;
    }

    .action-buttons {
        justify-content: center;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .modal-content {
        width: 95%;
        padding: 1.5rem;
    }

    .task-info {
        flex-direction: column;
        gap: 1rem;
    }

    .detail-tabs {
        flex-wrap: wrap;
    }

    .detail-tab {
        flex: 1;
        min-width: 100px;
    }

    .file-upload {
        flex-direction: column;
        text-align: center;
    }

    .reports-filters {
        flex-direction: column;
    }

    .chart-container {
        height: 300px;
        padding: 1rem;
    }

    .performance-table {
        overflow-x: auto;
    }

    .task-meta-details {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .task-header {
        flex-direction: column;
        gap: 0.5rem;
    }

    .task-meta {
        flex-direction: column;
        gap: 0.5rem;
        align-items: flex-start;
    }

    .modal-actions {
        flex-direction: column;
    }

    .toast {
        left: 20px;
        right: 20px;
        transform: translateY(-100px);
    }

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

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

.fade-in {
    animation: fadeIn 0.3s ease-out;
}

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

.slide-up {
    animation: slideUp 0.3s ease-out;
}

/* Focus States */
*:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:focus,
input:focus,
textarea:focus,
select:focus {
    outline: none;
    box-shadow: 0 0 0 3px var(--primary-color-20);
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000;
        --text-color: #000;
        --bg-color: #fff;
    }
}

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

/* Print Styles */
@media print {
    .header-controls,
    .nav-tabs,
    .controls-panel,
    .modal,
    .toast,
    .theme-toggle-auth {
        display: none !important;
    }
    
    .task-card {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #000;
    }
    
    body {
        background: white !important;
        color: black !important;
    }
}