:root {
    --bg: #fafafa;
    --surface: #ffffff;
    --text: #1a1a1a;
    --text-secondary: #6b7280;
    --border: #e5e7eb;
    --accent: #6366f1;
    --accent-hover: #4f46e5;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --info: #3b82f6;
    --radius: 12px;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
}

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

body {
    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* ── Navbar ── */

.navbar {
    background: var(--surface);
    padding: 0.875rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-brand {
    color: var(--accent);
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

.nav-links {
    display: flex;
    gap: 0.25rem;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    padding: 0.4rem 0.75rem;
    border-radius: 8px;
    transition: all 0.15s;
}

.nav-links a:hover {
    color: var(--accent);
    background: #f3f4f6;
}

/* ── Layout ── */

.container {
    max-width: 800px;
    margin: 2rem auto;
    padding: 0 1.25rem;
}

/* ── Cards ── */

.card {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 1.5rem;
    border: 1px solid var(--border);
    margin-bottom: 1rem;
}

.card h2 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 1rem;
    letter-spacing: -0.01em;
}

/* ── Auth Forms ── */

.auth-form {
    max-width: 380px;
    margin: 4rem auto;
    background: var(--surface);
    padding: 2rem;
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.auth-form h1 {
    margin-bottom: 0.5rem;
    text-align: center;
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

.auth-form > p:first-of-type {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
}

/* ── Forms ── */

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.375rem;
    font-weight: 500;
    font-size: 0.8125rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.625rem 0.875rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 0.9375rem;
    background: var(--bg);
    color: var(--text);
    transition: border-color 0.15s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

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

.field-error {
    color: var(--danger);
    font-size: 0.8rem;
    margin-top: 0.25rem;
    display: block;
}

/* ── Buttons ── */

.btn {
    display: inline-block;
    padding: 0.6rem 1.25rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.875rem;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.15s;
    text-align: center;
}

.btn-primary {
    background: var(--accent);
    color: #fff;
    width: 100%;
}

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

.btn-primary.btn-inline {
    width: auto;
}

.btn-secondary {
    background: #f3f4f6;
    color: var(--text);
}

.btn-secondary:hover {
    background: #e5e7eb;
}

.btn-success {
    background: var(--success);
    color: #fff;
}

.btn-success:hover {
    background: #059669;
}

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

.btn-danger:hover {
    background: #dc2626;
}

.btn-sm {
    padding: 0.35rem 0.75rem;
    font-size: 0.8125rem;
}

/* ── Alerts ── */

.alert {
    padding: 0.75rem 1rem;
    border-radius: 8px;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    font-weight: 500;
}

.alert-success {
    background: #ecfdf5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.alert-error {
    background: #fef2f2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

.alert-info {
    background: #eff6ff;
    color: #1e40af;
    border: 1px solid #bfdbfe;
}

/* ── Auth Links ── */

.auth-link {
    text-align: center;
    margin-top: 1rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.auth-link a {
    color: var(--accent);
    font-weight: 500;
    text-decoration: none;
}

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

/* ── Page Header ── */

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

.page-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

/* ── Stats Grid ── */

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.stat-card {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 1.25rem;
    text-align: center;
    border: 1px solid var(--border);
}

.stat-card .stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: -0.025em;
}

.stat-card .stat-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 500;
}

/* ── Streak ── */

.streak-display {
    text-align: center;
    padding: 0.5rem 0;
}

.streak-count {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--accent);
    letter-spacing: -0.04em;
    line-height: 1;
}

.streak-label {
    color: var(--text-secondary);
    font-size: 0.75rem;
    margin-top: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 500;
}

/* ── Task Grid (list page) ── */

.task-grid {
    display: flex;
    flex-direction: column;
    gap: 0.625rem;
}

.task-card {
    display: flex;
    flex-direction: column;
    gap: 0.625rem;
    padding: 1rem 1.25rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 10px;
    text-decoration: none;
    color: var(--text);
    transition: all 0.2s;
}

.task-card:hover {
    border-color: var(--accent);
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.1);
    transform: translateY(-1px);
}

.task-card-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 0.75rem;
}

.task-card-title {
    font-weight: 600;
    font-size: 0.9375rem;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    flex: 1;
}

.task-card-bottom {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.task-card-date {
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

.task-card-time {
    font-size: 0.75rem;
    color: var(--accent);
    font-weight: 600;
    background: rgba(99, 102, 241, 0.08);
    padding: 0.125rem 0.5rem;
    border-radius: 999px;
}

.task-row-sub {
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

/* ── Task List (used in friends) ── */

.task-list {
    list-style: none;
}

.task-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.875rem 0;
    border-bottom: 1px solid var(--border);
}

.task-item:last-child {
    border-bottom: none;
}

.task-meta {
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

/* ── Status Pills ── */

.status-pill {
    display: inline-block;
    padding: 0.2rem 0.625rem;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    white-space: nowrap;
}

.status-pending {
    background: #fef3c7;
    color: #92400e;
}

.status-in_progress {
    background: #dbeafe;
    color: #1e40af;
}

.status-completed {
    background: #d1fae5;
    color: #065f46;
}

.status-skipped {
    background: #f3f4f6;
    color: #4b5563;
}

/* ── Info Pills & Detail Pills ── */

.detail-pills {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: 0.75rem;
    flex-wrap: wrap;
}

.info-pill {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    background: var(--bg);
    padding: 0.2rem 0.625rem;
    border-radius: 999px;
    border: 1px solid var(--border);
}

/* ── Button Tabs ── */

.btn-tabs {
    display: flex;
    gap: 0.375rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border);
}

.btn-tab {
    padding: 0.4rem 0.875rem;
    border-radius: 8px;
    font-size: 0.8125rem;
    font-weight: 500;
    text-decoration: none;
    color: var(--text-secondary);
    background: var(--bg);
    border: 1px solid var(--border);
    transition: all 0.15s;
}

.btn-tab:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(99, 102, 241, 0.04);
}

.btn-tab-active {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.btn-tab-active:hover {
    background: var(--accent-hover);
    border-color: var(--accent-hover);
    color: #fff;
}

.badge-count {
    background: var(--danger);
    color: #fff;
    border-radius: 999px;
    padding: 0.05rem 0.4rem;
    font-size: 0.6875rem;
    font-weight: 700;
    margin-left: 0.25rem;
    vertical-align: middle;
}

/* ── Button Filters ── */

.btn-filters {
    display: flex;
    gap: 0.375rem;
    padding: 0.875rem 0 0;
    flex-wrap: wrap;
}

.btn-filter {
    padding: 0.3rem 0.75rem;
    border-radius: 999px;
    font-size: 0.8125rem;
    font-weight: 500;
    text-decoration: none;
    color: var(--text-secondary);
    background: var(--bg);
    border: 1px solid var(--border);
    transition: all 0.15s;
}

.btn-filter:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.btn-filter-active {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.btn-filter-active:hover {
    background: var(--accent-hover);
    border-color: var(--accent-hover);
    color: #fff;
}

/* ── Friends ── */

.friend-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.875rem 0;
    border-bottom: 1px solid var(--border);
}

.friend-item:last-child {
    border-bottom: none;
}

/* ── Empty State ── */

.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-secondary);
    font-size: 0.9375rem;
}

.empty-state a {
    color: var(--accent);
    font-weight: 500;
    text-decoration: none;
}

.empty-state a:hover {
    text-decoration: underline;
}

.empty-cta {
    margin-top: 0.75rem;
    text-decoration: none;
}

.empty-cta:hover {
    text-decoration: none;
}

/* ── Empty Card (task pages) ── */

.empty-card {
    text-align: center;
    padding: 3rem 1.5rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 1rem;
}

.empty-card-icon {
    font-size: 2.5rem;
    margin-bottom: 0.75rem;
    opacity: 0.4;
}

.empty-card-text {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

/* ── Welcome ── */

.welcome-text {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    margin-bottom: 1.5rem;
}

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

/* ── Section Headers ── */

.section-header {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 0.75rem;
}

/* ── Pagination ── */

.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem 0 0.25rem;
    border-top: 1px solid var(--border);
    margin-top: 0.5rem;
}

.btn-page {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.35rem 0.75rem;
    border-radius: 8px;
    font-size: 0.8125rem;
    font-weight: 500;
    text-decoration: none;
    color: var(--text-secondary);
    background: var(--bg);
    border: 1px solid var(--border);
    transition: all 0.15s;
}

.btn-page:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(99, 102, 241, 0.04);
}

.page-info {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* ── Back Link ── */

.detail-back {
    margin-bottom: 1rem;
}

.back-link {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.15s;
}

.back-link:hover {
    color: var(--accent);
}

/* ── Detail Page ── */

.detail-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
}

.detail-title {
    font-size: 1.375rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.3;
}

.detail-actions {
    display: flex;
    gap: 0.375rem;
    flex-shrink: 0;
}

.detail-body {
    margin-top: 1rem;
    font-size: 0.9375rem;
    line-height: 1.7;
    color: var(--text);
}

.detail-section {
    margin-top: 1.25rem;
    padding-top: 1.25rem;
    border-top: 1px solid var(--border);
}

.detail-label {
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 0.375rem;
}

/* ── Form Card ── */

.form-card {
    max-width: 520px;
}

.form-card-title {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 1.25rem;
}

.form-card-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: -0.75rem;
    margin-bottom: 1rem;
}

/* ── Form Layout ── */

.form-row {
    display: flex;
    gap: 0.75rem;
}

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

.inline-form .btn {
    margin-top: 0.25rem;
}

/* ── History Timeline ── */

.history-list {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.history-item {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 0.625rem 0;
    border-bottom: 1px solid var(--border);
}

.history-item:last-child {
    border-bottom: none;
}

.history-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent);
    margin-top: 0.4rem;
    flex-shrink: 0;
}

.history-content {
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
}

.history-transition {
    font-size: 0.875rem;
    font-weight: 500;
}

.history-note {
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

.history-time {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* ── Delete Preview ── */

.delete-preview {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

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