/* Light-first theme with optional dark-mode support via prefers-color-scheme */

/* ---------- Theme Tokens ---------- */
:root {
    /* Light palette */
    --bg: #f7f9fc;
    --card: #ffffff;
    --text: #0f172a;
    /* slate-900 */
    --muted: #475569;
    /* slate-600 */
    --border: #e2e8f0;
    /* slate-200 */
    --input-bg: #ffffff;
    --input-border: #cbd5e1;
    /* slate-300 */
    --accent: #2563eb;
    /* blue-600 */
    --accent-ink: #ffffff;
    --danger: #ef4444;
    /* red-500 */
    --danger-ink: #ffffff;
    --success-bg: #ecfdf5;
    /* emerald-50 */
    --success-text: #065f46;
    /* emerald-800 */
    --warning-bg: #fffbeb;
    /* amber-50 */
    --warning-text: #92400e;
    /* amber-800 */
    --danger-bg: #fef2f2;
    /* red-50 */
    --danger-text: #991b1b;
    /* red-800 */

    --radius-lg: 12px;
    --radius-md: 10px;
    --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
    --shadow-md: 0 6px 20px rgba(15, 23, 42, 0.08);
}

/* Optional: auto-dark if user prefers dark scheme */
@media (prefers-color-scheme: dark) {
    :root {
        --bg: #0f172a;
        /* slate-900 */
        --card: #111827;
        /* gray-900 */
        --text: #e5e7eb;
        /* gray-200 */
        --muted: #9ca3af;
        /* gray-400 */
        --border: #1f2937;
        /* gray-800 */
        --input-bg: #0b1220;
        --input-border: #1f2937;
        --accent: #3b82f6;
        /* blue-500 */
        --accent-ink: #0b1220;
        --danger: #ef4444;
        --danger-ink: #220909;
        --success-bg: #052e12;
        --success-text: #86efac;
        --warning-bg: #3a2e07;
        --warning-text: #fde68a;
        --danger-bg: #220909;
        --danger-text: #fecaca;

        --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.25);
        --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.35);
    }
}

/* ---------- Base ---------- */
* {
    box-sizing: border-box;
}

html,
body {
    margin: 0;
    padding: 0;
    font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif;
    background: var(--bg);
    color: var(--text);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--accent);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.container {
    max-width: 860px;
    margin: 0 auto;
    padding: 16px;
}

/* ---------- Header / Footer ---------- */
.header,
.footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 14px 16px;
    box-shadow: var(--shadow-sm);
}

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

.user {
    color: var(--muted);
    margin-right: 8px;
}

.footer {
    color: var(--muted);
    margin-top: 24px;
}

/* ---------- Cards / Surfaces ---------- */
.card {
    background: var(--card);
    padding: 16px;
    border-radius: var(--radius-lg);
    margin: 12px 0;
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
}

/* ---------- Forms ---------- */
label {
    display: block;
    margin: 10px 0 6px;
    color: var(--muted);
    font-weight: 600;
}

input[type="text"],
input[type="email"],
input[type="password"] {
    width: 100%;
    padding: 12px 14px;
    border-radius: 10px;
    border: 1px solid var(--input-border);
    background: var(--input-bg);
    color: var(--text);
    outline: none;
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
    box-shadow: var(--shadow-sm);
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="password"]:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.12);
}

/* ---------- Buttons ---------- */
.btn {
    background: var(--accent);
    color: var(--accent-ink);
    border: none;
    padding: 10px 14px;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 700;
    box-shadow: var(--shadow-sm);
    transition: transform 0.05s ease, box-shadow 0.2s ease, filter 0.2s ease;
}

.btn:hover {
    filter: brightness(1.05);
    box-shadow: var(--shadow-md);
}

.btn:active {
    transform: translateY(1px);
}

.btn.small {
    padding: 6px 10px;
    font-weight: 700;
}

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

/* ---------- Alerts ---------- */
.alert {
    padding: 10px 14px;
    border-radius: 10px;
    margin: 10px 0;
    border: 1px solid var(--border);
}

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

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

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

/* ---------- Errors list ---------- */
.errors {
    margin: 8px 0 0;
    padding-left: 18px;
    color: #b91c1c;
}

/* ---------- Todos ---------- */
.todos {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.todos li {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--card);
    border: 1px solid var(--border);
    padding: 12px 14px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

.todos li .text {
    flex: 1;
}

.todos li.done .text {
    text-decoration: line-through;
    color: var(--muted);
}

.empty {
    color: var(--muted);
    font-style: italic;
}

/* ---------- Utilities ---------- */
hr {
    border: 0;
    border-top: 1px solid var(--border);
    margin: 16px 0;
}