@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

:root {
    /* Core Colors */
    --bg-body: #F3F4F6;
    /* Cool gray */
    --bg-column: #F9FAFB;
    /* Very light gray */
    --bg-card: #FFFFFF;

    /* Text */
    --text-primary: #111827;
    --text-secondary: #6B7280;
    --text-tertiary: #9CA3AF;

    /* Brand Colors */
    --primary-color: #6366F1;
    /* Indigo */
    --primary-hover: #4F46E5;
    --primary-light: #E0E7FF;

    /* Functional Colors */
    --danger-color: #EF4444;
    --danger-hover: #DC2626;
    --danger-light: #FEE2E2;

    --success-color: #10B981;

    /* Priorities */
    --priority-low-bg: #D1FAE5;
    --priority-low-text: #065F46;

    --priority-medium-bg: #FEF3C7;
    --priority-medium-text: #92400E;

    --priority-high-bg: #FEE2E2;
    --priority-high-text: #991B1B;

    /* UI Tokens */
    --border-radius-sm: 6px;
    --border-radius: 12px;
    --border-radius-lg: 16px;

    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px 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);
    --shadow-modal: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

    --font-family: 'Inter', sans-serif;
    --transition-base: all 0.2s ease-in-out;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-body);
    color: var(--text-primary);
    line-height: 1.5;
    height: 100vh;
    overflow: hidden;
    background-image: radial-gradient(#E5E7EB 1px, transparent 1px);
    background-size: 24px 24px;
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100%;
}

/* --- Header --- */
.app-header {
    background-color: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    flex-shrink: 0;
    z-index: 10;
}

.app-header h1 {
    font-size: 1.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary-color), #818CF8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.025em;
}

.header-left .back-link {
    display: inline-block;
    margin-bottom: 0.35rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 600;
}

.header-left .back-link:hover {
    color: var(--primary-color);
    text-decoration: underline;
}
/* --- Toolbar --- */
.toolbar {
    background-color: white;
    padding: 0.75rem 2rem;
    display: flex;
    gap: 1.5rem;
    align-items: center;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    flex-shrink: 0;
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.filter-group label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.filter-group select {
    padding: 0.4rem 2rem 0.4rem 0.8rem;
    border: 1px solid #D1D5DB;
    border-radius: var(--border-radius-sm);
    font-size: 0.9rem;
    color: var(--text-primary);
    background-color: white;
    cursor: pointer;
    outline: none;
    transition: var(--transition-base);
}

.filter-group select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px var(--primary-light);
}

/* --- Board Layout --- */
.board-container {
    flex-grow: 1;
    display: flex;
    overflow-x: auto;
    overflow-y: auto;
    padding: 2rem;
    gap: 1.5rem;
    align-items: flex-start;
}

#board {
    display: flex;
    gap: 1.5rem;
    align-items: flex-start;
}

/* Custom Scrollbar */
.board-container::-webkit-scrollbar {
    height: 14px;
}

.board-container::-webkit-scrollbar-track {
    background: transparent;
}

.board-container::-webkit-scrollbar-thumb {
    background-color: rgba(156, 163, 175, 0.5);
    border-radius: 20px;
    border: 4px solid transparent;
    background-clip: content-box;
}

.board-container::-webkit-scrollbar-thumb:hover {
    background-color: rgba(156, 163, 175, 0.8);
}

/* --- Column --- */
.column {
    background-color: var(--bg-column);
    border-radius: var(--border-radius);
    width: 320px;
    min-width: 320px;
    max-height: 100%;
    display: flex;
    flex-direction: column;
    padding: 1rem;
    border: 1px solid rgba(0, 0, 0, 0.03);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-base);
}

.column-header {
    padding: 0.25rem 0.25rem 1rem;
    font-weight: 700;
    font-size: 1rem;
    color: var(--text-primary);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.column-title-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.card-count {
    background-color: var(--primary-light);
    color: var(--primary-color);
    border-radius: 999px;
    padding: 2px 8px;
    font-size: 0.75rem;
    font-weight: 600;
}

.column-actions {
    display: flex;
    gap: 4px;
    opacity: 0;
    transition: opacity 0.2s;
}

.column:hover .column-actions {
    opacity: 1;
}

.btn-icon {
    background: transparent;
    border: none;
    color: var(--text-tertiary);
    cursor: pointer;
    padding: 4px;
    border-radius: 4px;
    transition: color 0.2s, background-color 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-icon:hover {
    color: var(--text-primary);
    background-color: rgba(0, 0, 0, 0.05);
}

.card-list {
    flex-grow: 1;
    overflow-y: auto;
    min-height: 100px;
    padding: 4px;
    /* Space for focus rings/shadows */
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

/* Scrollbar for card list */
.card-list::-webkit-scrollbar {
    width: 6px;
}

.card-list::-webkit-scrollbar-thumb {
    background-color: rgba(0, 0, 0, 0.1);
    border-radius: 4px;
}

/* --- Card --- */
.card {
    background-color: var(--bg-card);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    padding: 1rem;
    cursor: grab;
    transition: all 0.2s cubic-bezier(0.25, 0.8, 0.25, 1);
    border: 1px solid transparent;
    position: relative;
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
    border-color: rgba(99, 102, 241, 0.1);
}

.card.dragging {
    opacity: 0.8;
    transform: rotate(3deg) scale(1.05);
    box-shadow: var(--shadow-lg);
    cursor: grabbing;
    z-index: 100;
}

.card-title {
    font-weight: 600;
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    line-height: 1.4;
}

.card-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}

.meta-item {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.badge-assignee,
.badge-project {
    background-color: #F3F4F6;
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 500;
    color: var(--text-primary);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.card-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.75rem;
    padding-top: 0.5rem;
    border-top: 1px solid #F3F4F6;
}

.priority-badge {
    padding: 2px 8px;
    border-radius: 4px;
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.65rem;
    letter-spacing: 0.05em;
}

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

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

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

/* --- Add Card / Column Buttons --- */
.add-card-btn {
    margin-top: 0.75rem;
    background: transparent;
    border: 1px dashed #D1D5DB;
    color: var(--text-secondary);
    padding: 0.75rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    width: 100%;
    text-align: center;
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition-base);
}

.add-card-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background-color: var(--primary-light);
}

.add-column-container {
    min-width: 320px;
    padding-top: 0;
}

.add-column-btn {
    width: 100%;
    height: 60px;
    background: rgba(255, 255, 255, 0.5);
    border: 2px dashed rgba(0, 0, 0, 0.1);
    border-radius: var(--border-radius);
    color: var(--text-secondary);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-base);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.add-column-btn:hover {
    background: white;
    border-color: var(--primary-color);
    color: var(--primary-color);
    box-shadow: var(--shadow-sm);
}

/* --- Buttons --- */
.btn {
    padding: 0.6rem 1.2rem;
    border-radius: var(--border-radius-sm);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: var(--transition-base);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    box-shadow: 0 2px 4px rgba(79, 70, 229, 0.3);
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 6px rgba(79, 70, 229, 0.4);
}

.btn-secondary {
    background-color: white;
    color: var(--text-secondary);
    border: 1px solid #D1D5DB;
}

.btn-secondary:hover {
    background-color: #F9FAFB;
    color: var(--text-primary);
    border-color: #9CA3AF;
}

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

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

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

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

/* --- Modal --- */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(17, 24, 39, 0.6);
    backdrop-filter: blur(4px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease;
}

/* Ensure edit modals appear above the detail view */
#card-modal,
#column-modal {
    z-index: 1010;
}

.modal:not(.hidden) {
    opacity: 1;
    pointer-events: auto;
}

.modal-content {
    background-color: white;
    border-radius: var(--border-radius-lg);
    width: 500px;
    max-width: 90%;
    box-shadow: var(--shadow-modal);
    display: flex;
    flex-direction: column;
    transform: scale(0.95);
    transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.modal:not(.hidden) .modal-content {
    transform: scale(1);
}

/* Full Screen Modal Modifier */
.modal-content.modal-full {
    width: 95%;
    height: 90%;
    max-width: 1200px;
}

.modal-header {
    padding: 1.5rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid #F3F4F6;
}

.modal-header h2 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.close-modal {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-tertiary);
    transition: color 0.2s;
    line-height: 1;
}

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

.modal-body {
    padding: 2rem;
    overflow-y: auto;
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.form-group input[type="text"],
.form-group input[type="date"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #D1D5DB;
    border-radius: var(--border-radius-sm);
    font-family: inherit;
    font-size: 0.95rem;
    transition: border-color 0.2s, box-shadow 0.2s;
    background-color: #F9FAFB;
}

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

.form-row {
    display: flex;
    gap: 1rem;
}

.form-row .form-group {
    flex: 1;
}

.modal-actions {
    display: flex;
    justify-content: space-between;
    margin-top: 1rem;
    padding-top: 1.5rem;
    border-top: 1px solid #F3F4F6;
}

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

.right-actions {
    display: flex;
    gap: 0.75rem;
}

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

/* --- Table View --- */
.table-container {
    width: 100%;
    overflow-x: auto;
}

.card-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.95rem;
}

.card-table th {
    text-align: left;
    padding: 1rem;
    border-bottom: 2px solid #E5E7EB;
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.card-table td {
    padding: 1rem;
    border-bottom: 1px solid #F3F4F6;
    color: var(--text-primary);
}

.card-table tr:hover {
    background-color: #F9FAFB;
    cursor: pointer;
}

.card-table tr:last-child td {
    border-bottom: none;
}

.date-overdue,
.card-table td.date-overdue {
    color: var(--danger-color);
    font-weight: 700;
}

.date-due-soon,
.card-table td.date-due-soon {
    color: #D97706;
    /* Amber-600 */
    font-weight: 700;
}

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

/* --- View Tabs --- */
.view-tabs {
    display: flex;
    gap: 0.5rem;
    padding: 0 0 0.75rem 0;
}

.tab {
    padding: 0.5rem 1rem;
    border: 1px solid #E5E7EB;
    background: #F9FAFB;
    border-radius: var(--border-radius-sm);
    color: var(--text-secondary);
    cursor: pointer;
    font-weight: 600;
    transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.tab.active {
    background: #FFFFFF;
    color: var(--text-primary);
    border-color: var(--primary-color);
}

/* --- Gantt --- */
.gantt-container {
    background: #FFFFFF;
    border-radius: var(--border-radius-lg);
    padding: 1rem;
    box-shadow: 0 8px 24px rgba(17, 24, 39, 0.08);
    margin-top: 0.5rem;
    flex: 1;
    min-height: 0;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.gantt-toolbar {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 0.75rem;
    flex-wrap: wrap;
}

.gantt-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.gantt-controls input[type="range"] {
    width: 200px;
}

.gantt-controls select {
    padding: 0.4rem 2rem 0.4rem 0.8rem;
    border: 1px solid #D1D5DB;
    border-radius: var(--border-radius-sm);
    font-size: 0.9rem;
    color: var(--text-primary);
    background-color: white;
    cursor: pointer;
    outline: none;
    transition: var(--transition-base);
}

.gantt-controls select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px var(--primary-light);
}

.gantt-chart {
    position: relative;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    flex: 1;
    min-height: 0;
    overflow: auto;
}

.gantt-axis {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}

.gantt-axis-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
    flex-shrink: 0;
}

.gantt-axis-spacer {
    flex: 0 0 180px;
}

.gantt-axis-track {
    position: relative;
    flex: 1;
    height: 28px;
}

.gantt-tick {
    position: absolute;
    top: 0;
    transform: translateX(-50%);
    font-size: 0.8rem;
    color: var(--text-secondary);
    white-space: nowrap;
}

.gantt-row {
    position: relative;
    padding: 0.25rem 0;
}

.gantt-row-label {
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.gantt-project {
    margin-bottom: 1rem;
}

.gantt-project-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    margin-bottom: 0.25rem;
}

.gantt-rows {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.gantt-card-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: grab;
}

.gantt-card-row.dragging {
    opacity: 0.6;
}

.gantt-card-title {
    flex: 0 0 180px;
    font-weight: 600;
    color: var(--text-primary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    cursor: pointer;
}

.gantt-add-btn {
    background: none;
    border: 1px dashed #D1D5DB;
    color: var(--primary-color);
    border-radius: var(--border-radius-sm);
    padding: 0.25rem 0.75rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-base);
}

.gantt-add-btn:hover {
    background: var(--primary-light);
}

.gantt-row-track {
    position: relative;
    background: #F3F4F6;
    border-radius: var(--border-radius-sm);
    height: 28px;
    overflow: hidden;
    flex: 1;
}

.gantt-bar {
    position: absolute;
    top: 6px;
    height: 16px;
    border-radius: var(--border-radius-sm);
    background: var(--primary-color);
    color: #fff;
    display: flex;
    align-items: center;
    padding: 0 8px;
    font-size: 0.85rem;
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
    box-shadow: 0 4px 10px rgba(99, 102, 241, 0.25);
    cursor: grab;
}

.gantt-bar.priority-low {
    background: #10B981;
}

.gantt-bar.priority-medium {
    background: #3B82F6;
}

.gantt-bar.priority-high {
    background: #EF4444;
}

.gantt-bar.gantt-bar-done {
    background: #9CA3AF;
    box-shadow: none;
}

.gantt-bar-label {
    pointer-events: none;
}

.gantt-handle {
    position: absolute;
    top: 0;
    width: 8px;
    height: 100%;
    background: rgba(255, 255, 255, 0.25);
    cursor: col-resize;
}

.gantt-handle.left {
    left: 0;
}

.gantt-handle.right {
    right: 0;
}

.gantt-empty {
    color: var(--text-secondary);
    font-size: 0.95rem;
    padding: 0.5rem 0;
}