:root {
    --bg: #f6f7f9;
    --card: #ffffff;
    --text: #111827;
    --muted: #5d6675;
    --line: #d7dce3;
    --blue: #2563eb;
    --blue-dark: #1d4ed8;
    --danger: #b33630;
    --ok: #1f7a4c;
}

* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: var(--bg);
    color: var(--text);
}
a { color: var(--blue); text-decoration: none; }
a, button, input, select, textarea { -webkit-tap-highlight-color: rgba(37,99,235,.14); }
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: 3px solid rgba(37,99,235,.24);
    outline-offset: 3px;
}
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 14px; }
.topbar {
    background: #fff;
    border-bottom: 1px solid var(--line);
    position: sticky; top: 0; z-index: 5;
}
.topbar .wrap { display: flex; align-items: center; justify-content: space-between; min-height: 60px; }
.brand { font-weight: 700; color: var(--text); }
.shell { display: grid; grid-template-columns: 220px 1fr; min-height: 100vh; }
.sidebar { padding: 18px; background: #fff; border-right: 1px solid var(--line); }
.sidebar nav { display: grid; gap: 8px; margin: 14px 0; }
.content { padding: 20px; }
.hero { padding: 18px 0 12px; }
.hero.compact { padding-bottom: 6px; }
.card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 16px;
    margin: 0 0 14px;
    box-shadow: 0 10px 30px rgba(17,24,39,0.04);
}
.card.narrow { max-width: 460px; margin: 40px auto; }
.grid { display: grid; gap: 14px; }
.grid.stats { grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); }
.stats .card { display: grid; gap: 8px; }
.stats strong { font-size: 28px; }
.result-grid { grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); }
.emphasis { border-color: rgba(37,99,235,.25); }
.stack > * + * { margin-top: 12px; }
.grid-form { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); }
.grid-form label, .stack label { display: grid; gap: 6px; font-size: 14px; }
input, select, textarea, button {
    font: inherit;
    padding: 10px 12px;
    border-radius: 10px;
    border: 1px solid var(--line);
    background: #fff;
    color: var(--text);
}
button, .button {
    display: inline-flex; align-items: center; justify-content: center;
    background: var(--blue); color: #fff; border-color: var(--blue); cursor: pointer;
    padding: 10px 14px; border-radius: 10px;
}
.secondary { background: #fff; color: var(--text); border: 1px solid var(--line); }
.checkbox { display: flex !important; align-items: center; gap: 8px; }
.inline-checks { display: flex; flex-wrap: wrap; gap: 14px; }
table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
.alt-list { display: grid; gap: 12px; }
.alt-item { border: 1px solid var(--line); border-radius: 14px; padding: 16px; }
.surface-link {
    display: grid;
    gap: 12px;
    min-height: 44px;
    border-radius: 14px;
    transition: transform .14s ease, border-color .14s ease, box-shadow .14s ease;
}
.surface-link:hover {
    transform: translateY(-1px);
}
.surface-link:active {
    transform: translateY(0);
}
.surface-link__title {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    width: fit-content;
    color: var(--text);
}
.surface-link__title:hover,
.surface-link__title:focus-visible {
    color: var(--blue-dark);
}
.split-header { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-bottom: 14px; }
.flash { padding: 12px 14px; border-radius: 10px; margin-bottom: 14px; }
.flash-success { background: rgba(31,122,76,.12); color: var(--ok); }
.flash-error { background: rgba(179,54,48,.12); color: var(--danger); }
.flash-info { background: rgba(37,99,235,.10); color: var(--blue-dark); }
.prose ul { padding-left: 18px; }
.note ul { margin: 0; padding-left: 18px; }
@media (max-width: 900px) {
    .shell { grid-template-columns: 1fr; }
    .sidebar { border-right: 0; border-bottom: 1px solid var(--line); }
}
@media (max-width: 760px) {
    .wrap { padding: 0 12px; }
    .hero { padding: 14px 0 10px; }
    .card { padding: 14px; border-radius: 12px; }
    .grid-form { grid-template-columns: 1fr; }
    .inline-checks { gap: 10px; }
}