:root {
  --primary: #2563eb;
  --primary-50: #eff6ff;
  --primary-100: #dbeafe;
  --primary-700: #1d4ed8;
  --ok: #16a34a;
  --ok-50: #f0fdf4;
  --warn: #d97706;
  --warn-50: #fffbeb;
  --bad: #dc2626;
  --bad-50: #fef2f2;
  --text: #1e293b;
  --muted: #64748b;
  --line: #e2e8f0;
  --bg: #f1f5f9;
  --card: #ffffff;
  --soft: #f8fafc;
  --line2: #cbd5e1;
  --radius: 10px;
  --shadow: 0 1px 2px rgba(15, 23, 42, .06), 0 1px 3px rgba(15, 23, 42, .08);
  font-family: "Inter", "Segoe UI", system-ui, -apple-system, Roboto, Arial, sans-serif;
  color: var(--text);
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); font-size: 15px; line-height: 1.5; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { margin: 0 0 .5em; line-height: 1.3; }
h1 { font-size: 1.5rem; }
h2 { font-size: 1.2rem; }
h3 { font-size: 1.05rem; }
.muted { color: var(--muted); }
.small { font-size: .85rem; }
.hidden { display: none !important; }
.nowrap { white-space: nowrap; }
.right { text-align: right; }
.center { text-align: center; }
.grow { flex: 1; }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.stack > * + * { margin-top: 12px; }
.grid { display: grid; gap: 16px; }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); }

/* ---------- Bố cục giáo viên ---------- */
.layout { display: flex; min-height: 100vh; }
.sidebar {
  width: 236px; flex-shrink: 0; background: var(--card); border-right: 1px solid var(--line);
  position: sticky; top: 0; height: 100vh; display: flex; flex-direction: column;
}
.brand { display: flex; align-items: center; gap: 10px; padding: 18px 20px; font-weight: 700; font-size: 1.15rem; color: var(--primary); }
.brand .logo { width: 34px; height: 34px; border-radius: 9px; background: var(--primary); color: #fff; display: grid; place-items: center; font-weight: 800; }
.nav { padding: 8px 12px; flex: 1; overflow: auto; }
.nav a {
  display: flex; align-items: center; gap: 12px; padding: 10px 12px; border-radius: 8px;
  color: var(--text); font-weight: 500; margin-bottom: 2px;
}
.nav a:hover { background: var(--bg); text-decoration: none; }
.nav a.active { background: var(--primary-50); color: var(--primary); }
.nav svg { width: 20px; height: 20px; flex-shrink: 0; }
.nav .sep { height: 1px; background: var(--line); margin: 10px 4px; }
.main { flex: 1; min-width: 0; display: flex; flex-direction: column; }
.topbar {
  height: 60px; background: var(--card); border-bottom: 1px solid var(--line); display: flex; align-items: center;
  padding: 0 24px; gap: 16px; position: sticky; top: 0; z-index: 10;
}
.topbar .title { font-weight: 600; font-size: 1.05rem; }
.content { padding: 24px; max-width: 1280px; width: 100%; }
.menu-btn { display: none; }
@media (max-width: 860px) {
  .sidebar { position: fixed; left: -260px; z-index: 50; transition: left .2s; box-shadow: var(--shadow); }
  .sidebar.open { left: 0; }
  .menu-btn { display: inline-flex; }
  .content { padding: 16px; }
  .topbar { padding: 0 16px; }
}

/* ---------- Thành phần ---------- */
.card { background: var(--card); border-radius: var(--radius); box-shadow: var(--shadow); padding: 20px; }
.card + .card { margin-top: 16px; }
.grid > .card + .card { margin-top: 0; }
.card-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 14px; flex-wrap: wrap; }
.card-head h2, .card-head h3 { margin: 0; }
.page-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 18px; flex-wrap: wrap; }
.page-head h1 { margin: 0; }
.stat { display: flex; gap: 14px; align-items: center; }
.stat .icon { width: 48px; height: 48px; border-radius: 12px; display: grid; place-items: center; flex-shrink: 0; }
.stat .icon svg { width: 24px; height: 24px; }
.stat .value { font-size: 1.6rem; font-weight: 700; line-height: 1.1; }
.stat .label { color: var(--muted); font-size: .9rem; }
.c-blue { background: var(--primary-50); color: var(--primary); }
.c-green { background: var(--ok-50); color: var(--ok); }
.c-amber { background: var(--warn-50); color: var(--warn); }
.c-red { background: var(--bad-50); color: var(--bad); }
.c-violet { background: #f5f3ff; color: #7c3aed; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 8px 14px;
  border-radius: 8px; border: 1px solid var(--line); background: var(--card); color: var(--text);
  font: inherit; font-weight: 500; cursor: pointer; white-space: nowrap; text-decoration: none !important;
}
.btn:hover { background: var(--bg); }
.btn:disabled { opacity: .55; cursor: not-allowed; }
.btn svg { width: 18px; height: 18px; }
.btn-primary { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-700); }
.btn-danger { color: var(--bad); }
.btn-danger:hover { background: var(--bad-50); }
.btn-success { background: var(--ok); border-color: var(--ok); color: #fff; }
.btn-success:hover { background: #15803d; }
.btn-sm { padding: 4px 10px; font-size: .85rem; }
.btn-lg { padding: 12px 20px; font-size: 1.05rem; }
.btn-icon { padding: 6px; }
.btn-block { width: 100%; }

.badge { display: inline-block; padding: 2px 9px; border-radius: 999px; font-size: .78rem; font-weight: 600; background: var(--bg); color: var(--muted); }
.badge.blue { background: var(--primary-100); color: var(--primary-700); }
.badge.green { background: #dcfce7; color: #15803d; }
.badge.amber { background: #fef3c7; color: #b45309; }
.badge.red { background: #fee2e2; color: #b91c1c; }

label.field { display: block; }
label.field > span { display: block; font-weight: 500; font-size: .9rem; margin-bottom: 4px; color: var(--text); }
input[type=text], input[type=password], input[type=number], input[type=date], input[type=datetime-local], input[type=search], select, textarea {
  width: 100%; padding: 8px 11px; border: 1px solid var(--line2); border-radius: 8px; font: inherit; color: inherit; background: var(--card);
}
input:focus, select:focus, textarea:focus { outline: 2px solid var(--primary-100); border-color: var(--primary); }
textarea { resize: vertical; min-height: 70px; }
textarea.code { font-family: ui-monospace, Consolas, monospace; font-size: .9rem; }
.check { display: inline-flex; align-items: center; gap: 8px; cursor: pointer; user-select: none; }
.check input { width: 17px; height: 17px; accent-color: var(--primary); }
.form-grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }

.table-wrap { overflow-x: auto; }
table.table { width: 100%; border-collapse: collapse; }
.table th, .table td { padding: 10px 12px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: middle; }
.table th { font-size: .82rem; text-transform: uppercase; letter-spacing: .02em; color: var(--muted); font-weight: 600; background: var(--soft); }
.table tr:hover td { background: var(--soft); }
.table td.actions { white-space: nowrap; text-align: right; }
.empty { text-align: center; color: var(--muted); padding: 36px 12px; }

.tabs { display: flex; gap: 4px; border-bottom: 1px solid var(--line); margin-bottom: 16px; overflow-x: auto; }
.tabs button { background: none; border: 0; padding: 10px 14px; font: inherit; font-weight: 500; color: var(--muted); cursor: pointer; border-bottom: 2px solid transparent; white-space: nowrap; }
.tabs button.active { color: var(--primary); border-bottom-color: var(--primary); }

.toast-box { position: fixed; right: 16px; bottom: 16px; z-index: 200; display: flex; flex-direction: column; gap: 8px; }
.toast { background: #0f172a; color: #fff; padding: 10px 16px; border-radius: 8px; box-shadow: var(--shadow); max-width: 360px; animation: fade .2s; }
.toast.error { background: var(--bad); }
.toast.ok { background: var(--ok); }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } }

.modal-back { position: fixed; inset: 0; background: rgba(15, 23, 42, .45); z-index: 100; display: grid; place-items: center; padding: 16px; }
.modal { background: var(--card); border-radius: 12px; width: 100%; max-width: 560px; max-height: calc(100vh - 32px); overflow: auto; box-shadow: 0 20px 50px rgba(0, 0, 0, .25); }
.modal.wide { max-width: 860px; }
.modal-head { padding: 16px 20px; border-bottom: 1px solid var(--line); display: flex; justify-content: space-between; align-items: center; }
.modal-head h3 { margin: 0; }
.modal-body { padding: 20px; }
.modal-foot { padding: 14px 20px; border-top: 1px solid var(--line); display: flex; justify-content: flex-end; gap: 8px; }

.bars { display: flex; align-items: flex-end; gap: 6px; height: 160px; padding-top: 18px; }
.bars .bar { flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: flex-end; height: 100%; min-width: 0; }
.bars .bar i { display: block; width: 100%; background: var(--primary); border-radius: 4px 4px 0 0; min-height: 2px; position: relative; }
.bars .bar i b { position: absolute; top: -18px; left: 0; right: 0; text-align: center; font-size: .75rem; font-weight: 600; color: var(--text); font-style: normal; }
.bars .bar span { font-size: .72rem; color: var(--muted); margin-top: 4px; white-space: nowrap; }
.progress { height: 8px; background: var(--line); border-radius: 99px; overflow: hidden; }
.progress > i { display: block; height: 100%; background: var(--primary); }

/* ---------- Câu hỏi ---------- */
.q-card { border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; background: var(--card); }
.q-card + .q-card { margin-top: 12px; }
.q-num { font-weight: 700; color: var(--primary); }
.q-text { margin: 6px 0 10px; overflow-wrap: anywhere; }
.q-img { max-width: 100%; max-height: 360px; display: block; margin: 8px 0; border-radius: 6px; }
.opt { display: flex; gap: 10px; align-items: flex-start; padding: 9px 12px; border: 1px solid var(--line); border-radius: 8px; margin-top: 6px; cursor: pointer; background: var(--card); }
.opt:hover { border-color: var(--primary); }
.opt.sel { border-color: var(--primary); background: var(--primary-50); }
.opt.right { border-color: var(--ok); background: var(--ok-50); }
.opt.wrong { border-color: var(--bad); background: var(--bad-50); }
.opt .letter { width: 26px; height: 26px; border-radius: 50%; border: 1px solid var(--line2); display: grid; place-items: center; font-weight: 600; flex-shrink: 0; font-size: .85rem; background: var(--card); }
.opt.sel .letter { background: var(--primary); color: #fff; border-color: var(--primary); }
.opt.right .letter { background: var(--ok); color: #fff; border-color: var(--ok); }
.opt.wrong .letter { background: var(--bad); color: #fff; border-color: var(--bad); }
.opt .otext { flex: 1; min-width: 0; overflow-wrap: anywhere; padding-top: 2px; }
.tf-row { display: flex; gap: 10px; align-items: center; padding: 8px 0; border-bottom: 1px dashed var(--line); }
.tf-row:last-child { border-bottom: 0; }
.tf-row .otext { flex: 1; min-width: 0; }
.tf-btns { display: flex; gap: 6px; }
.tf-btns button { min-width: 54px; }
.tf-btns button.on-t { background: var(--ok); color: #fff; border-color: var(--ok); }
.tf-btns button.on-f { background: var(--bad); color: #fff; border-color: var(--bad); }
.explain { margin-top: 10px; padding: 10px 12px; background: var(--warn-50); border-radius: 8px; border-left: 3px solid var(--warn); }

/* Trình soạn câu hỏi */
.qe { border: 1px solid var(--line); border-radius: var(--radius); padding: 14px; background: var(--card); }
.qe + .qe { margin-top: 12px; }
.qe-head { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-bottom: 10px; }
.qe-opt { display: flex; gap: 8px; align-items: center; margin-top: 6px; }
.qe-opt textarea { min-height: 38px; height: 38px; }
.qe-opt .letter { font-weight: 700; width: 22px; text-align: center; }
.essay-imgs img, .essay-thumb img { height: 110px; max-width: 160px; object-fit: cover; border-radius: 8px; border: 1px solid var(--line); cursor: zoom-in; background: #fff; }
.essay-thumb { position: relative; display: inline-block; }
.essay-thumb button { position: absolute; top: -6px; right: -6px; width: 26px; height: 26px; border-radius: 50%; border: 0; background: var(--bad); color: #fff; font-size: 16px; line-height: 1; cursor: pointer; }
.preview { margin-top: 8px; padding: 10px 12px; background: var(--soft); border-radius: 8px; border: 1px dashed var(--line); }

/* ---------- Trang đăng nhập ---------- */
.auth-wrap { min-height: 100vh; display: grid; place-items: center; padding: 16px; background: linear-gradient(135deg, #dbeafe, #f1f5f9 60%); }
.auth { width: 100%; max-width: 400px; }
.auth .brand { justify-content: center; padding: 0 0 18px; font-size: 1.4rem; }

/* ---------- Trang học sinh ---------- */
.s-top { background: var(--primary); color: #fff; }
.s-top .inner { max-width: 1080px; margin: 0 auto; padding: 12px 16px; display: flex; align-items: center; gap: 12px; }
.s-top .brand { color: #fff; padding: 0; }
.s-top .brand .logo { background: var(--card); color: var(--primary); }
.s-top .btn { background: rgba(255, 255, 255, .15); border-color: transparent; color: #fff; }
.s-wrap { max-width: 1080px; margin: 0 auto; padding: 20px 16px 60px; }
.item { display: flex; gap: 14px; align-items: center; padding: 14px 0; border-bottom: 1px solid var(--line); }
.item:last-child { border-bottom: 0; }
.item .icon { width: 44px; height: 44px; border-radius: 10px; display: grid; place-items: center; flex-shrink: 0; }
.item .icon svg { width: 22px; height: 22px; }
.exam-layout { display: grid; grid-template-columns: 1fr 260px; gap: 16px; align-items: start; }
.exam-side { position: sticky; top: 12px; }
.timer { font-size: 1.8rem; font-weight: 700; text-align: center; font-variant-numeric: tabular-nums; }
.timer.low { color: var(--bad); }
.qnav { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; }
.qnav a { display: grid; place-items: center; height: 36px; border-radius: 6px; border: 1px solid var(--line); color: var(--text); font-weight: 600; font-size: .9rem; }
.qnav a.ans { background: var(--primary); border-color: var(--primary); color: #fff; }
.qnav a:hover { text-decoration: none; border-color: var(--primary); }
.qnav a.ok { background: var(--ok); border-color: var(--ok); color: #fff; }
.qnav a.ko { background: var(--bad); border-color: var(--bad); color: #fff; }
.qnav a.part { background: var(--warn); border-color: var(--warn); color: #fff; }
.score-big { font-size: 3rem; font-weight: 800; color: var(--primary); line-height: 1; }
@media (max-width: 860px) {
  .exam-layout { grid-template-columns: 1fr; }
  .exam-side { position: fixed; left: 0; right: 0; bottom: 0; top: auto; z-index: 20; border-radius: 12px 12px 0 0; box-shadow: 0 -4px 16px rgba(0, 0, 0, .12); }
  .exam-side .qnav-wrap { display: none; }
  .exam-side.open .qnav-wrap { display: block; max-height: 40vh; overflow: auto; }
  .exam-main { padding-bottom: 150px; }
  .timer { font-size: 1.4rem; }
}

@media print {
  .sidebar, .topbar, .no-print { display: none !important; }
  .content { padding: 0; }
  .card { box-shadow: none; }
}

/* ---------- Biểu đồ tiến bộ, bảng chủ đề ---------- */
.chart { width: 100%; height: auto; display: block; }
.chart .grid { stroke: var(--line); }
.chart text { fill: var(--muted); font-size: 11px; }
.chart .line { fill: none; stroke: var(--primary); stroke-width: 2.5; stroke-linejoin: round; }
.chart circle { fill: #fff; stroke-width: 2.5; }
.chart circle.exam { stroke: var(--primary); }
.chart circle.hw { stroke: var(--warn); }
.dot { display: inline-block; width: 10px; height: 10px; border-radius: 50%; border: 2.5px solid var(--primary); vertical-align: -1px; }
.dot.hw { border-color: var(--warn); }
.dot.ok { background: var(--ok); border-color: var(--ok); }
.dot.part { background: var(--warn); border-color: var(--warn); }
.dot.ko { background: var(--bad); border-color: var(--bad); }
.part-scores { display: flex; justify-content: center; flex-wrap: wrap; gap: 10px 28px; margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--line); }
.review-nav { grid-template-columns: repeat(auto-fill, minmax(40px, 1fr)); }
.q-card[hidden] { display: none; }
.explain summary { list-style-position: inside; }
.heat td.cell { text-align: center; font-weight: 600; font-size: .85rem; min-width: 64px; }
.heat th.topic { white-space: normal; min-width: 90px; text-transform: none; letter-spacing: 0; }
.picker-list { max-height: 260px; overflow: auto; border: 1px solid var(--line); border-radius: 8px; padding: 8px 12px; }
.picker-list .cls { font-weight: 600; font-size: .85rem; color: var(--muted); margin: 8px 0 4px; }
.picker-list .check { display: flex; padding: 3px 0; }
.lbl { display: block; font-weight: 500; font-size: .9rem; margin-bottom: 6px; color: var(--text); }
/* .right ở đây là "đáp án đúng", không phải căn lề phải */
.opt.right { text-align: left; }
@media (max-width: 520px) {
  .grid-4 { grid-template-columns: 1fr 1fr; gap: 10px; }
  .grid-4 .stat .icon { display: none; }
  .grid-4 .card { padding: 14px; }
  .stat .value { font-size: 1.3rem; }
}

/* ---------- Chụp & chấm (điện thoại) ---------- */
.scan { padding-bottom: 110px; }
.scan .item.card { padding: 14px; }
.shot-group { margin-top: 12px; }
.shot-group.unknown { border: 2px solid var(--warn); }
.shot-group select { font-size: 1rem; }
.thumbs { display: flex; gap: 8px; overflow-x: auto; margin-top: 10px; }
.thumb { position: relative; flex-shrink: 0; }
.thumb img { height: 110px; border-radius: 8px; border: 1px solid var(--line); display: block; }
.thumb button { position: absolute; top: 4px; right: 4px; width: 26px; height: 26px; border-radius: 50%; border: 0; background: rgba(15, 23, 42, .7); color: #fff; font-size: 14px; }
.thumb i { position: absolute; left: 4px; bottom: 4px; background: var(--ok); color: #fff; font-style: normal; font-size: .7rem; font-weight: 700; padding: 1px 6px; border-radius: 6px; }
.send-bar { position: fixed; left: 0; right: 0; bottom: 0; padding: 12px 16px calc(12px + env(safe-area-inset-bottom)); background: rgba(255, 255, 255, .96); box-shadow: 0 -4px 16px rgba(0, 0, 0, .08); z-index: 30; }
.scan .table td, .scan .table th { padding: 8px 6px; }
.scan select, .scan input, .scan textarea { font-size: 16px; } /* tránh iPhone tự phóng to khi chạm ô nhập */
/* bảng duyệt đáp án trên điện thoại: mỗi câu một khối dọc */
@media (max-width: 600px) {
  .scan .table thead { display: none; }
  .scan .table tr { display: block; padding: 10px 0; border-bottom: 1px solid var(--line); }
  .scan .table td { display: block; border: 0; padding: 3px 0; }
  .scan .table td:last-child::before { content: 'Đáp án đúng: '; color: var(--muted); font-weight: 400; }
  .scan .table textarea, .scan .table input[type=text] { max-width: none !important; width: 100%; }
}

/* ---------- Bản đồ kiến thức ---------- */
.km-row { padding: 8px 0; border-bottom: 1px dashed var(--line); }
.km-row summary { cursor: pointer; list-style: none; }
.km-row summary::-webkit-details-marker { display: none; }
.km-lessons { display: flex; flex-wrap: wrap; gap: 6px; padding: 8px 0 4px 12px; }
.km-chip { font-size: .82rem; border: 1.5px solid var(--line); border-radius: 999px; padding: 2px 10px; background: var(--card); }

/* ---- Giao diện tối ---- */
:root[data-theme="dark"] {
  --primary: #60a5fa; --primary-50: #172554; --primary-100: #1e3a8a; --primary-700: #93c5fd;
  --ok: #4ade80; --ok-50: #052e16; --warn: #fbbf24; --warn-50: #422006; --bad: #f87171; --bad-50: #450a0a;
  --text: #e2e8f0; --muted: #94a3b8; --line: #334155; --line2: #475569; --bg: #0b1220; --card: #1e293b; --soft: #172033;
  --shadow: 0 1px 2px rgba(0, 0, 0, .4);
  color-scheme: dark;
}
:root[data-theme="dark"] .btn-primary, :root[data-theme="dark"] .opt.sel .letter, :root[data-theme="dark"] .qnav a.ans { color: #0b1220; }
:root[data-theme="dark"] .badge.amber { background: #422006; color: #fcd34d; }
:root[data-theme="dark"] .brand .logo { color: #0b1220; }
:root[data-theme="dark"] .badge.green { background: #052e16; color: #86efac; }
:root[data-theme="dark"] .badge.red { background: #450a0a; color: #fca5a5; }
:root[data-theme="dark"] .c-violet { background: #2e1065; color: #c4b5fd; }
:root[data-theme="dark"] .nav a:hover { background: var(--soft); }
:root[data-theme="dark"] .auth-wrap { background: linear-gradient(135deg, #0b1220, #172554); }
:root[data-theme="dark"] .s-top { background: #1e3a8a; }
:root[data-theme="dark"] .s-top .brand .logo { background: #e2e8f0; color: #1e3a8a; }
:root[data-theme="dark"] .q-img { background: #fff; border-radius: 6px; }
:root[data-theme="dark"] .katex { color: inherit; }

/* Màn chờ vào thi: gọn một trang */
.intro-info { display: grid; grid-template-columns: 1fr 1fr; gap: 6px 16px; }
.intro-info .row { gap: 8px; flex-wrap: nowrap; }
.intro-info svg { width: 18px; height: 18px; flex: none; }
@media (max-width: 480px) { .intro-info { grid-template-columns: 1fr; } }

/* Cây "Theo đề" trong Kho: tiêu đề nhóm, số La Mã, số đề */
.kh-sec { margin: 18px 0 6px; padding: 0 4px 6px; font-weight: 800; font-size: 1.12rem; color: var(--primary); border-bottom: 3px solid #e6b86a; cursor: pointer; }
.kh-sec:first-child { margin-top: 4px; }
.kh-row { display: flex; align-items: center; gap: 8px; padding: 9px 8px; border-radius: 8px; cursor: pointer; }
.kh-row:hover { background: rgba(127, 127, 127, .12); }
.kh-row.on { background: var(--primary); color: #fff; }
.kh-row.lv0 { font-weight: 700; font-size: 1.02rem; margin-top: 4px; }
.kh-row.lv2 { padding-left: 26px; font-weight: 600; }
.kh-row.lv3 { padding-left: 44px; font-size: .92rem; }
.kh-row.lv1 { padding-left: 26px; }
.kh-no { width: 26px; flex: none; text-align: right; font: 700 .72rem ui-monospace, Consolas, monospace; opacity: .6; }
.kh-lb { flex: 1; min-width: 0; overflow-wrap: anywhere; }
.kh-n { flex: none; font: .78rem ui-monospace, Consolas, monospace; opacity: .65; }
.kh-chev { flex: none; width: 18px; text-align: center; font-weight: 700; }

/* Logo thương hiệu: thay chữ "T" bằng biểu tượng √T (public/logo.svg) */
.brand .logo, .s-top .brand .logo, :root[data-theme="dark"] .brand .logo, :root[data-theme="dark"] .s-top .brand .logo {
  background: url(/logo.svg) center / contain no-repeat; color: transparent; font-size: 0; border-radius: 0; box-shadow: none;
}
.brand .logo { width: 36px; height: 36px; }