:root {
    color-scheme: light;
    --background: #f5f7fb;
    --card: #ffffff;
    --border: #d9e0ea;
    --text: #1f2937;
    --muted: #667085;
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --danger: #dc2626;
    --success-bg: #dcfce7;
    --success-text: #166534;
    --error-bg: #fee2e2;
    --error-text: #991b1b;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    display: flex;
    background: var(--background);
    color: var(--text);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.sidebar {
    width: 260px;
    padding: 28px 22px;
    background: #111827;
    color: #ffffff;
}

.sidebar h1 {
    margin: 0 0 28px;
    font-size: 20px;
}

.sidebar nav {
    display: grid;
    gap: 8px;
}

.sidebar a {
    padding: 12px 14px;
    border-radius: 10px;
    color: #cbd5e1;
    text-decoration: none;
}

.sidebar a.active,
.sidebar a:hover {
    background: #1f2937;
    color: #ffffff;
}

.content {
    width: calc(100% - 260px);
    padding: 32px;
}

.page-header {
    margin-bottom: 24px;
}

.page-header h2 {
    margin: 4px 0 8px;
    font-size: 32px;
}

.eyebrow {
    margin: 0;
    color: var(--primary);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.card {
    margin-bottom: 20px;
    padding: 22px;
    border: 1px solid var(--border);
    border-radius: 16px;
    background: var(--card);
    box-shadow: 0 8px 24px rgba(15, 23, 42, 0.05);
}

.create-card summary {
    cursor: pointer;
    font-size: 18px;
    font-weight: 700;
}

.create-card[open] summary {
    margin-bottom: 18px;
}

.form-grid,
.filter-form {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
}

.filter-form {
    grid-template-columns: 2fr 1fr 1fr auto;
    align-items: end;
}

.full-width {
    grid-column: 1 / -1;
}

label {
    display: grid;
    gap: 8px;
    color: var(--muted);
    font-size: 14px;
    font-weight: 600;
}

input,
select,
textarea {
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 10px 12px;
    color: var(--text);
    font: inherit;
}

textarea {
    resize: vertical;
}

select[multiple] {
    min-height: 96px;
}

button {
    border: 0;
    border-radius: 10px;
    padding: 11px 16px;
    cursor: pointer;
    font-weight: 700;
}

.primary-button {
    background: var(--primary);
    color: #ffffff;
}

.primary-button:hover {
    background: var(--primary-dark);
}

.secondary-button {
    background: #e0e7ff;
    color: #3730a3;
}

.danger-button {
    background: var(--danger);
    color: #ffffff;
}

.task-layout {
    display: grid;
    grid-template-columns: minmax(280px, 1fr) minmax(420px, 2fr);
    gap: 20px;
}

.task-items {
    display: grid;
    gap: 10px;
}

.task-item {
    display: grid;
    gap: 6px;
    padding: 14px;
    border: 1px solid var(--border);
    border-radius: 12px;
    color: var(--text);
    text-decoration: none;
}

.task-item.selected,
.task-item:hover {
    border-color: var(--primary);
    background: #eff6ff;
}

.task-item span,
.empty-state {
    color: var(--muted);
}

.stacked-form {
    display: grid;
    gap: 16px;
    margin-top: 28px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

.delete-form {
    margin-top: 16px;
}

.alert {
    margin-bottom: 18px;
    padding: 12px 14px;
    border-radius: 10px;
    font-weight: 700;
}

.alert.success {
    background: var(--success-bg);
    color: var(--success-text);
}

.alert.error {
    background: var(--error-bg);
    color: var(--error-text);
}

@media (max-width: 960px) {
    body {
        display: block;
    }

    .sidebar,
    .content {
        width: 100%;
    }

    .task-layout,
    .form-grid,
    .filter-form {
        grid-template-columns: 1fr;
    }
}