* { box-sizing: border-box; }

body {
    margin: 0;
    background: var(--color-background);
    color: var(--color-text);
    font: var(--font-size-base)/var(--line-height) var(--font-ui);
}

.topbar {
    min-height: 64px;
    padding: 0 max(var(--space-5), calc((100% - var(--content-width)) / 2));
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--color-brand);
    color: var(--color-brand-text);
}

.brand {
    color: var(--color-brand-text);
    text-decoration: none;
    font-weight: 750;
}

.brand span {
    display: inline-grid;
    place-items: center;
    width: 31px;
    height: 31px;
    margin-right: var(--space-2);
    border-radius: 9px;
    background: var(--color-accent);
    color: var(--color-accent-text);
}

.account { display: flex; align-items: center; gap: 14px; }
.account form { margin: 0; }
.link-button { border: 0; background: none; color: var(--color-accent); text-decoration: underline; cursor: pointer; }
.top-link { color: var(--color-brand-text); text-decoration: none; font-size: 13px; opacity: .9; }
.top-link:hover { color: var(--color-accent); }

.shell { max-width: var(--content-width); margin: 0 auto; padding: var(--space-6) var(--space-5) 60px; }
.hero { display: flex; align-items: flex-end; justify-content: space-between; margin-bottom: var(--space-5); }
.hero.compact { align-items: center; }
.hero h1, .auth-card h1 { margin: 3px 0 var(--space-1); font-size: clamp(28px, 4vw, 42px); line-height: 1.12; }
.eyebrow { text-transform: uppercase; letter-spacing: .14em; font-size: 12px; font-weight: 800; color: var(--color-link); }
.muted, small { color: var(--color-muted); }

.search { display: flex; gap: var(--space-3); margin: 20px 0; }
.search input, .stack input {
    width: 100%;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-control);
    padding: 13px 15px;
    font: inherit;
    background: var(--color-surface);
}

.search input:focus, .stack input:focus { outline: 3px solid color-mix(in srgb, var(--color-link) 18%, transparent); border-color: var(--color-link); }
.primary { display: inline-flex; align-items: center; justify-content: center; border: 0; border-radius: var(--radius-control); background: var(--color-brand); color: var(--color-brand-text); padding: 12px 20px; font-weight: 750; text-decoration: none; cursor: pointer; }
.primary:hover { filter: brightness(1.12); }
.primary:focus-visible, a:focus-visible, button:focus-visible { outline: 3px solid var(--color-accent); outline-offset: 2px; }

.panel, .auth-card { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-card); padding: 22px; box-shadow: var(--shadow-card); }
.panel { margin-top: 18px; }
.panel h2 { margin: 0 0 14px; font-size: 20px; }
.panel-head { display: flex; align-items: center; justify-content: space-between; }
.panel-head span, .badge { background: var(--color-soft); border-radius: 99px; padding: var(--space-1) 10px; font-size: 13px; }

.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); gap: var(--space-3); }
.class-card { display: flex; flex-direction: column; gap: 5px; padding: var(--space-4); border: 1px solid var(--color-border); border-radius: 14px; color: inherit; text-decoration: none; }
.class-card:hover, .list-row:hover { border-color: var(--color-link); background: color-mix(in srgb, var(--color-soft) 45%, var(--color-surface)); }

.list { display: grid; }
.list-row { display: flex; justify-content: space-between; align-items: center; gap: var(--space-4); padding: 13px var(--space-2); border-bottom: 1px solid var(--color-border); color: inherit; text-decoration: none; }
.list-row:last-child { border-bottom: 0; }
.list-row div { display: flex; flex-direction: column; }
.row-meta { text-align: right; }
.back { display: inline-block; margin-bottom: 18px; color: var(--color-link); text-decoration: none; }
.teacher { display: flex; flex-direction: column; text-align: right; }
.table-scroll { overflow-x: auto; }
.data-table { width: 100%; min-width: 1100px; border-collapse: collapse; }
.data-table th, .data-table td { padding: .55rem; border-bottom: 1px solid var(--border); text-align: left; vertical-align: top; }
.data-table th { color: var(--muted); font-size: .8rem; white-space: nowrap; }
.data-table input { min-width: 120px; }
.new-row { background: color-mix(in srgb, var(--accent) 7%, transparent); }

.details-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 18px; }
.details-grid .panel { margin: 0; }
dl { display: grid; grid-template-columns: minmax(150px, 1fr) 2fr; gap: 0; margin: 0; }
dt, dd { margin: 0; padding: 10px 0; border-bottom: 1px solid var(--color-border); }
dt { color: var(--color-muted); }

.auth-card { max-width: 430px; margin: 7vh auto; }
.stack { display: grid; gap: var(--space-4); }
.stack label { font-weight: 650; }
.stack input { display: block; margin-top: 6px; }
.alert { margin: 14px 0; padding: 11px 13px; border-radius: var(--radius-small); background: var(--color-danger-bg); color: var(--color-danger-text); }
.notice { margin: 14px 0; padding: 11px 13px; border-radius: var(--radius-small); background: var(--color-success-bg); color: var(--color-success-text); }
.danger-panel { border-color: #f0caca; }
.button.danger { background: #b42318; color: #fff; border-color: #b42318; }
.button.secondary { background: #fff; color: var(--color-ink); }
.confirm-dialog { border: 0; border-radius: 16px; padding: 24px; max-width: 480px; width: calc(100% - 32px); box-shadow: 0 20px 60px #17212b33; }
.confirm-dialog::backdrop { background: #17212b66; }
.confirm-dialog textarea { width: 100%; margin-top: 6px; }
.dialog-actions { display: flex; gap: 10px; justify-content: flex-end; margin-top: 18px; }
.deletion-item { display: grid; gap: 8px; }
.student-edit { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.inline-form textarea { min-width: 260px; }
.student-edit label:last-of-type { grid-column: 1 / -1; }
@media (max-width: 720px) { .student-edit { grid-template-columns: 1fr; } .student-edit label:last-of-type { grid-column: auto; } }
.empty { color: var(--color-muted); }
.admin-list { display: grid; gap: 10px; }
.admin-item { border: 1px solid var(--color-border); border-radius: 12px; padding: 12px 14px; }
.admin-item summary { display: flex; justify-content: space-between; gap: 14px; cursor: pointer; }
.admin-item summary span { color: var(--color-muted); font-size: 13px; }
.admin-form { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 14px; }
.admin-form label, .class-edit label { display: grid; gap: 5px; font-weight: 650; }
.admin-form input, .admin-form select, .class-edit input { width: 100%; border: 1px solid var(--color-border); border-radius: var(--radius-control); padding: 10px 12px; font: inherit; background: var(--color-surface); }
.admin-form .check { display: flex; align-items: center; gap: 8px; font-weight: 500; }
.admin-form .check input { width: auto; }
.secondary { border: 1px solid var(--color-border); border-radius: var(--radius-control); background: var(--color-surface); color: var(--color-text); padding: 10px 14px; font: inherit; font-weight: 650; cursor: pointer; }
.secondary:hover { border-color: var(--color-link); }
.inline-form { display: flex; align-items: center; gap: 12px; margin-top: 12px; }
.class-edit { display: grid; grid-template-columns: 1fr 1.4fr 1fr auto; gap: 12px; align-items: end; border-bottom: 1px solid var(--color-border); padding: 10px 0; }
.class-edit > div { display: grid; gap: 4px; }

@media (max-width: 700px) {
    .topbar { padding: 0 var(--space-4); }
    .account > span { display: none; }
    .shell { padding: var(--space-5) var(--space-4); }
    .hero { align-items: flex-start; gap: 14px; }
    .hero.compact { flex-direction: column; }
    .teacher { text-align: left; }
    .search { flex-direction: column; }
    .details-grid { grid-template-columns: 1fr; }
    .list-row { align-items: flex-start; }
    .row-meta { text-align: right; }
    dl { grid-template-columns: 1fr; }
    dd { padding-top: 0; }
    .admin-form, .class-edit { grid-template-columns: 1fr; }
    .admin-item summary { flex-direction: column; gap: 4px; }
    .inline-form { align-items: flex-start; flex-direction: column; }
}