/* ─── CSS Variables ──────────────────────────────────────────────────────────── */
:root {
    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --primary-light: #eef2ff;
    --secondary: #64748b;
    --success: #16a34a;
    --success-light: #f0fdf4;
    --danger: #dc2626;
    --danger-hover: #b91c1c;
    --danger-light: #fef2f2;
    --warning: #d97706;
    --warning-light: #fffbeb;
    --info: #2563eb;
    --info-light: #eff6ff;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;
    --white: #ffffff;
    --radius: 8px;
    --radius-lg: 12px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
    --transition: all 0.2s ease;
}

/* ─── Reset & Base ──────────────────────────────────────────────────────────── */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--gray-800);
    background: var(--gray-50);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-hover); }

img { max-width: 100%; }

/* ─── Container ─────────────────────────────────────────────────────────────── */
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ─── Navbar ────────────────────────────────────────────────────────────────── */
.navbar {
    background: var(--white);
    border-bottom: 1px solid var(--gray-200);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-brand {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--gray-900);
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-brand:hover { color: var(--primary); }

.nav-icon { font-size: 1.4rem; }

.nav-menu {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-link {
    padding: 8px 16px;
    border-radius: var(--radius);
    color: var(--gray-600);
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition);
}

.nav-link:hover { background: var(--gray-100); color: var(--gray-900); }
.nav-link.active { background: var(--primary-light); color: var(--primary); }
.nav-link-logout:hover { background: var(--danger-light); color: var(--danger); }

.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    flex-direction: column;
    gap: 5px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--gray-700);
    border-radius: 2px;
    transition: var(--transition);
}

/* ─── Main Content ──────────────────────────────────────────────────────────── */
.main-content {
    flex: 1;
    padding: 30px 0;
}

/* ─── Footer ────────────────────────────────────────────────────────────────── */
.footer {
    background: var(--white);
    border-top: 1px solid var(--gray-200);
    padding: 20px 0;
    text-align: center;
    color: var(--gray-500);
    font-size: 0.85rem;
    margin-top: auto;
}

/* ─── Cards ─────────────────────────────────────────────────────────────────── */
.card {
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.card-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--gray-200);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
}

.card-header h2 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--gray-900);
}

.card-body { padding: 24px; }

/* ─── Stats Grid ────────────────────────────────────────────────────────────── */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
}

.stat-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 20px 24px;
    box-shadow: var(--shadow);
    border: 1px solid var(--gray-200);
    transition: var(--transition);
}

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

.stat-card .stat-icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    margin-bottom: 12px;
}

.stat-card .stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--gray-900);
    line-height: 1.2;
}

.stat-card .stat-label {
    font-size: 0.85rem;
    color: var(--gray-500);
    margin-top: 4px;
}

/* ─── Buttons ───────────────────────────────────────────────────────────────── */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    line-height: 1.4;
    white-space: nowrap;
}

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

.btn-success { background: var(--success); color: var(--white); }
.btn-success:hover { background: #15803d; color: var(--white); }

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

.btn-outline {
    background: transparent;
    color: var(--gray-700);
    border: 1px solid var(--gray-300);
}
.btn-outline:hover { background: var(--gray-100); }

.btn-sm { padding: 6px 12px; font-size: 0.8rem; }
.btn-lg { padding: 12px 28px; font-size: 1rem; }

.btn-group { display: flex; gap: 8px; flex-wrap: wrap; }

/* ─── Forms ─────────────────────────────────────────────────────────────────── */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 6px;
}

.form-control {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 0.9rem;
    color: var(--gray-800);
    background: var(--white);
    transition: var(--transition);
    outline: none;
    font-family: inherit;
}

.form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}

textarea.form-control { min-height: 100px; resize: vertical; }

select.form-control {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2364748b' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
}

.form-hint {
    font-size: 0.8rem;
    color: var(--gray-500);
    margin-top: 4px;
}

/* ─── Auth Pages ────────────────────────────────────────────────────────────── */
.auth-wrapper {
    min-height: calc(100vh - 40px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.auth-card {
    width: 100%;
    max-width: 420px;
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.auth-header {
    padding: 32px 32px 0;
    text-align: center;
}

.auth-header .auth-logo {
    font-size: 2.5rem;
    margin-bottom: 8px;
}

.auth-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
}

.auth-header p {
    color: var(--gray-500);
    font-size: 0.9rem;
    margin-top: 4px;
}

.auth-body { padding: 24px 32px 32px; }

.auth-footer {
    text-align: center;
    padding: 0 32px 24px;
    font-size: 0.875rem;
    color: var(--gray-500);
}

/* ─── Alerts ────────────────────────────────────────────────────────────────── */
.alert {
    padding: 12px 16px;
    border-radius: var(--radius);
    margin-bottom: 20px;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 10px;
    animation: slideDown 0.3s ease;
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

.alert-success { background: var(--success-light); color: #166534; border: 1px solid #bbf7d0; }
.alert-error   { background: var(--danger-light); color: #991b1b; border: 1px solid #fecaca; }
.alert-warning { background: var(--warning-light); color: #92400e; border: 1px solid #fde68a; }
.alert-info    { background: var(--info-light); color: #1e40af; border: 1px solid #bfdbfe; }

.alert-icon { font-weight: bold; font-size: 1.1rem; }

/* ─── Error List ────────────────────────────────────────────────────────────── */
.error-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.error-list li {
    color: var(--danger);
    font-size: 0.875rem;
    padding: 4px 0;
}

.error-list li::before {
    content: '• ';
    font-weight: bold;
}

/* ─── Task List ─────────────────────────────────────────────────────────────── */
.task-list {
    list-style: none;
}

.task-item {
    display: flex;
    align-items: center;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-100);
    gap: 16px;
    transition: var(--transition);
}

.task-item:last-child { border-bottom: none; }
.task-item:hover { background: var(--gray-50); }

.task-item.completed-task .task-title {
    text-decoration: line-through;
    color: var(--gray-400);
}

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

.task-title {
    font-weight: 600;
    color: var(--gray-800);
    font-size: 0.95rem;
    display: block;
}

.task-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 6px;
    font-size: 0.8rem;
    color: var(--gray-500);
    flex-wrap: wrap;
}

.task-description {
    font-size: 0.85rem;
    color: var(--gray-500);
    margin-top: 4px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.task-actions {
    display: flex;
    gap: 6px;
    flex-shrink: 0;
}

.task-overdue {
    color: var(--danger) !important;
    font-weight: 600;
}

/* ─── Badges ────────────────────────────────────────────────────────────────── */
.badge {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--white);
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

/* ─── Filters ───────────────────────────────────────────────────────────────── */
.filters-bar {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.filter-select {
    padding: 6px 32px 6px 10px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 0.85rem;
    color: var(--gray-700);
    background: var(--white);
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2364748b' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 8px center;
    outline: none;
    cursor: pointer;
}

.filter-select:focus { border-color: var(--primary); }

.search-input {
    padding: 6px 12px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 0.85rem;
    outline: none;
    width: 200px;
    max-width: 100%;
}

.search-input:focus { border-color: var(--primary); }

/* ─── Pagination ────────────────────────────────────────────────────────────── */
.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
    padding: 20px 24px;
    border-top: 1px solid var(--gray-200);
}

.pagination a, .pagination span {
    padding: 8px 14px;
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--gray-600);
    transition: var(--transition);
}

.pagination a:hover { background: var(--gray-100); }
.pagination .active { background: var(--primary); color: var(--white); }
.pagination .disabled { opacity: 0.4; pointer-events: none; }

/* ─── Empty State ───────────────────────────────────────────────────────────── */
.empty-state {
    text-align: center;
    padding: 48px 24px;
    color: var(--gray-500);
}

.empty-state .empty-icon { font-size: 3rem; margin-bottom: 16px; }
.empty-state h3 { font-size: 1.1rem; color: var(--gray-700); margin-bottom: 8px; }
.empty-state p { font-size: 0.9rem; margin-bottom: 20px; }

/* ─── Page Header ───────────────────────────────────────────────────────────── */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    flex-wrap: wrap;
    gap: 12px;
}

.page-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
}

/* ─── Profile ───────────────────────────────────────────────────────────────── */
.profile-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.profile-section h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--gray-200);
}

/* ─── Utility ───────────────────────────────────────────────────────────────── */
.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }

/* ─── Responsive ────────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
    .nav-toggle { display: flex; }

    .nav-menu {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--white);
        border-bottom: 1px solid var(--gray-200);
        box-shadow: var(--shadow-md);
        flex-direction: column;
        padding: 12px;
    }

    .nav-menu.active { display: flex; }

    .nav-link { padding: 12px 16px; width: 100%; text-align: left; }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .profile-grid {
        grid-template-columns: 1fr;
    }

    .task-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .task-actions {
        align-self: flex-end;
        margin-top: 8px;
    }

    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .filters-bar {
        flex-direction: column;
        align-items: stretch;
    }

    .search-input { width: 100%; }
}

@media (max-width: 480px) {
    .stats-grid { grid-template-columns: 1fr; }
    .auth-body, .auth-header, .auth-footer { padding-left: 20px; padding-right: 20px; }
    .card-body { padding: 16px; }
    .task-item { padding: 12px 16px; }
}