/* Custom design tokens */
:root {
    --font-family: "IBM Plex Sans", Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --font-family-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --primary-contrast: #ffffff;
    --primary-focus: rgba(79, 70, 229, 0.18);

    --color: #111827;
    --color-muted: #6b7280;
    --color-bg: #ffffff;
    --color-border: #e5e7eb;
    --color-card-bg: #ffffff;

    --color-error: #dc2626;
    --color-info: #2563eb;

    --story-state-drafted-color: #7f8c8d;
    --story-state-refined-color: #2980b9;
    --story-state-started-color: #e67e22;
    --story-state-finished-color: #8e44ad;
    --story-state-delivered-color: #16a085;
    --story-state-checked-color: #2ecc71;
    --story-state-done-color: #27ae60;

    --story-backlog-icebox-active-color: #0284c7;
    --story-backlog-trash-color: var(--color-error);

    --project-color-1: #0f766e;
    --project-color-2: #7c3aed;
    --project-color-3: #c2410c;
    --project-color-4: #0369a1;
    --project-color-5: #be123c;
    --project-color-6: #4d7c0f;
    --project-color-7: #9333ea;
    --project-color-8: #b45309;

    --border-radius: 0.375rem;
    --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.04);
    --story-container-label-max-width: 8rem;
}

@media (prefers-color-scheme: dark) {
    :root {
        --color: #f9fafb;
        --color-muted: #9ca3af;
        --color-bg: #111827;
        --color-border: #374151;
        --color-card-bg: #1f2937;
        --color-error: #f87171;
        --color-info: #60a5fa;
        --story-backlog-icebox-active-color: #38bdf8;
    }
}

html[data-theme="light"] {
    color-scheme: light;
    --color: #111827;
    --color-muted: #6b7280;
    --color-bg: #ffffff;
    --color-border: #e5e7eb;
    --color-card-bg: #ffffff;
    --color-error: #dc2626;
    --color-info: #2563eb;
    --story-backlog-icebox-active-color: #0284c7;
}

html[data-theme="dark"] {
    color-scheme: dark;
    --color: #f9fafb;
    --color-muted: #9ca3af;
    --color-bg: #111827;
    --color-border: #374151;
    --color-card-bg: #1f2937;
    --color-error: #f87171;
    --color-info: #60a5fa;
    --story-backlog-icebox-active-color: #38bdf8;
}

/* Box model reset */
*, *::before, *::after {
    box-sizing: border-box;
}

/* Base */
html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
}

body {
    margin: 0;
    font-family: var(--font-family);
    font-size: 1rem;
    line-height: 1.5;
    color: var(--color);
    background: var(--color-bg);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    margin: 0 0 0.5rem;
    font-weight: 600;
    line-height: 1.25;
}

p {
    margin: 0 0 1rem;
}

small {
    font-size: 0.875em;
}

/* Links */
a {
    color: var(--primary);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Lists */
ul, ol {
    margin: 0 0 1rem;
    padding-left: 1.5rem;
}

li {
    margin-bottom: 0.25rem;
}

/* Grouping */
hgroup {
    margin: 0 0 1rem;
}

hgroup > * {
    margin: 0;
}

/* Semantic block elements */
article {
    padding: 1rem;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    background: var(--color-card-bg);
    box-shadow: var(--card-shadow);
    margin-bottom: 1rem;
}

article > header {
    margin-bottom: 0.75rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--color-border);
}

section {
    margin-bottom: 1rem;
}

/* Container utility */
.container {
    width: 100%;
    max-width: 75rem;
    margin-left: auto;
    margin-right: auto;
    padding-left: 1rem;
    padding-right: 1rem;
}

/* Forms */
input,
select,
textarea {
    display: block;
    width: 100%;
    margin-bottom: 0.75rem;
    padding: 0.5rem 0.75rem;
    font-family: var(--font-family);
    font-size: 1rem;
    line-height: 1.5;
    color: var(--color);
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    appearance: none;
    -webkit-appearance: none;
    transition: border-color 0.15s, box-shadow 0.15s;
}

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

select {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath fill='none' stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.5rem center;
    background-size: 1em;
    padding-right: 2rem;
}

textarea {
    resize: vertical;
}

label {
    display: block;
    margin-bottom: 0.375rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color);
}

/* Buttons */
button,
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.375rem;
    padding: 0.5rem 1rem;
    font-family: var(--font-family);
    font-size: 0.875rem;
    font-weight: 500;
    line-height: 1.25;
    color: var(--primary-contrast);
    background: var(--primary);
    border: 1px solid var(--primary);
    border-radius: var(--border-radius);
    cursor: pointer;
    text-decoration: none;
    transition: background 0.15s, border-color 0.15s, box-shadow 0.15s;
    white-space: nowrap;
    appearance: none;
    -webkit-appearance: none;
}

button:hover,
.btn:hover {
    background: var(--primary-hover);
    border-color: var(--primary-hover);
    text-decoration: none;
}

button:focus-visible,
.btn:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px var(--primary-focus);
}

button.secondary,
.btn.secondary {
    color: var(--primary);
    background: transparent;
    border-color: var(--color-border);
}

button.secondary:hover,
.btn.secondary:hover {
    background: var(--primary-focus);
    border-color: var(--primary);
}

button.outline,
.btn.outline {
    color: var(--color-muted);
    background: transparent;
    border-color: var(--color-border);
}

button.outline:hover,
.btn.outline:hover {
    color: var(--color);
    background: color-mix(in srgb, var(--color-border) 30%, transparent);
}

button.secondary.outline,
.btn.secondary.outline {
    color: var(--color-muted);
    background: transparent;
    border-color: var(--color-border);
}

button.secondary.outline:hover,
.btn.secondary.outline:hover {
    color: var(--color);
    background: color-mix(in srgb, var(--color-border) 30%, transparent);
}

/* Details / Summary */
details {
    margin-bottom: 1rem;
}

summary {
    cursor: pointer;
    list-style: none;
    user-select: none;
}

summary::-webkit-details-marker {
    display: none;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

th, td {
    padding: 0.6rem 0.75rem;
    border-bottom: 1px solid var(--color-border);
    text-align: left;
}

th {
    font-weight: 600;
    color: var(--color-muted);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

/* aria-busy loading spinner */
[aria-busy="true"] {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--color-muted);
    font-size: 0.875rem;
}

[aria-busy="true"]::before {
    content: "";
    display: inline-block;
    width: 0.875rem;
    height: 0.875rem;
    border: 2px solid var(--color-border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
    flex-shrink: 0;
}

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