.qfb-page {
    --b-blue: #0b4a8a;
    --b-blue-dark: #083a6e;
    --b-ink: #0f172a;
    --b-ink-2: #334155;
    --b-muted: #64748b;
    --b-line: #e2e8f0;
    --b-bg: #ffffff;
    --b-soft: #f8fafc;
    --b-tint: #edf3f9;
    --b-green: #15803d;
    --b-card: #ffffff;
    --b-shadow: 0 1px 2px rgba(15, 23, 42, .06), 0 8px 24px rgba(15, 23, 42, .06);

    background: var(--b-bg);
    color: var(--b-ink-2);
    font-size: 15px;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

html.dark .qfb-page {
    --b-ink: #f1f5f9;
    --b-ink-2: #cbd5e1;
    --b-muted: #94a3b8;
    --b-line: #1e293b;
    --b-bg: #0b1220;
    --b-soft: #111c2e;
    --b-tint: #16263c;
    --b-card: #101a2b;
    --b-shadow: 0 1px 2px rgba(0, 0, 0, .4);
}

.qfb-wrap { width: 100%; max-width: 1080px; margin: 0 auto; padding: 0 1.15rem; }

.qfb-nav {
    position: sticky; top: 0; z-index: 40;
    background: color-mix(in srgb, var(--b-bg) 90%, transparent);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--b-line);
}

.qfb-nav-in {
    display: flex; align-items: center; flex-wrap: wrap;
    gap: .5rem 1rem; min-height: 60px; padding-block: .5rem;
}

.qfb-brand {
    display: inline-flex; align-items: center; gap: .5rem;
    font-weight: 800; font-size: 1rem; letter-spacing: -.02em;
    color: var(--b-ink); text-decoration: none;
}

.qfb-brand img { display: block; width: auto; height: 30px; }

.qfb-links {
    display: flex; gap: 1rem; order: 3; flex-basis: 100%;
    overflow-x: auto; scrollbar-width: none; white-space: nowrap;
    padding-bottom: .3rem; margin-bottom: -.3rem;
}
.qfb-links::-webkit-scrollbar { display: none; }

.qfb-links a {
    color: var(--b-muted); text-decoration: none; font-size: .86rem; font-weight: 500;
    white-space: nowrap;
}
.qfb-links a:hover, .qfb-links .qfb-on { color: var(--b-blue); }

.qfb-cta { display: flex; align-items: center; gap: .45rem; margin-left: auto; order: 2; }

/* ── The collapsed menu ────────────────────────────────────────────────────────────────
   Under 900px the header used to push six links onto a second row and scroll them sideways.
   One small arrow now holds them: <details> needs no script, works before the Blazor circuit
   connects, and the links stay in the HTML for a crawler either way. */
.qfb-nav-in { position: relative; }

.qfb-menu { display: none; order: 4; }

.qfb-menu-btn {
    list-style: none; cursor: pointer;
    display: grid; place-items: center;
    width: 36px; height: 36px;
    border: 1px solid var(--b-line); border-radius: 999px;
    background: var(--b-bg); color: var(--b-ink-2);
}
.qfb-menu-btn::-webkit-details-marker { display: none; }
.qfb-menu-btn:hover { color: var(--b-blue); border-color: var(--b-blue); }
.qfb-menu-btn .bi { font-size: 1rem; transition: transform .15s ease; }
.qfb-menu[open] .qfb-menu-btn .bi { transform: rotate(180deg); }

.qfb-menu-panel {
    position: absolute; left: 0; right: 0; top: calc(100% + .35rem);
    display: flex; flex-direction: column; gap: .1rem;
    padding: .5rem;
    background: var(--b-bg);
    border: 1px solid var(--b-line); border-radius: 12px;
    box-shadow: var(--b-shadow);
    z-index: 60;
}
.qfb-menu-panel a {
    display: block; padding: .55rem .7rem; border-radius: 8px;
    color: var(--b-ink-2); text-decoration: none; font-weight: 600; font-size: .9rem;
}
.qfb-menu-panel a:hover { background: var(--b-soft); color: var(--b-blue); }
.qfb-menu-panel .qfb-on { color: var(--b-blue); }
.qfb-menu-panel .qfb-langs { margin: .45rem .35rem .1rem; }

.qfb-btn {
    display: inline-flex; align-items: center; justify-content: center; gap: .4rem;
    padding: .5rem .95rem; border-radius: 8px; border: 1px solid transparent;
    font-size: .84rem; font-weight: 600; text-decoration: none; white-space: nowrap;
}

.qfb-btn-primary { background: var(--b-blue); color: #fff; }
.qfb-btn-primary:hover { background: var(--b-blue-dark); color: #fff; }
.qfb-btn-ghost { border-color: var(--b-line); color: var(--b-ink); }
.qfb-btn-ghost:hover { border-color: var(--b-blue); color: var(--b-blue); }

.qfb-main { flex: 1 0 auto; padding: 2.4rem 0 3.4rem; }

.qfb-hero { max-width: 760px; margin-bottom: 2rem; }
.qfb-eyebrow {
    display: inline-flex; align-items: center; gap: .35rem;
    font-size: .7rem; font-weight: 700; letter-spacing: .09em; text-transform: uppercase;
    color: var(--b-blue); background: var(--b-tint);
    padding: .28rem .68rem; border-radius: 999px; margin-bottom: .8rem;
}
.qfb-h1 { color: var(--b-ink); font-size: clamp(1.55rem, 3.4vw, 2.2rem); line-height: 1.22; letter-spacing: -.025em; margin: 0 0 .7rem; }
.qfb-lead { font-size: 1rem; color: var(--b-ink-2); margin: 0; }

.qfb-tags { display: flex; flex-wrap: wrap; gap: .4rem; margin-top: .9rem; }
.qfb-tag {
    font-size: .74rem; font-weight: 600; color: var(--b-blue);
    background: var(--b-tint); border-radius: 999px; padding: .22rem .6rem;
    text-decoration: none;
}
.qfb-tag:hover { background: var(--b-blue); color: #fff; }

.qfb-grid { display: grid; grid-template-columns: 1fr; gap: 1rem; }

.qfb-card {
    display: flex; flex-direction: column; gap: .5rem;
    background: var(--b-card); border: 1px solid var(--b-line); border-radius: 14px;
    padding: 1.15rem 1.2rem; box-shadow: var(--b-shadow);
}
.qfb-card:hover { border-color: var(--b-blue); }
.qfb-card h2 { margin: 0; font-size: 1.05rem; line-height: 1.35; }
.qfb-card h2 a { color: var(--b-ink); text-decoration: none; }
.qfb-card h2 a:hover { color: var(--b-blue); }
.qfb-card p { margin: 0; font-size: .88rem; color: var(--b-ink-2); }
.qfb-meta {
    display: flex; flex-wrap: wrap; gap: .35rem 1rem;
    font-size: .76rem; color: var(--b-muted);
}

.qfb-article { max-width: 780px; margin: 0 auto; }
.qfb-article .qfb-h1 { margin-bottom: .55rem; }

.qfb-body { color: var(--b-ink-2); font-size: .96rem; }
.qfb-body h2 {
    color: var(--b-ink); font-size: 1.28rem; line-height: 1.3;
    margin: 2rem 0 .6rem; letter-spacing: -.01em;
}
.qfb-body h3 { color: var(--b-ink); font-size: 1.05rem; margin: 1.5rem 0 .45rem; }
.qfb-body p { margin: 0 0 .95rem; }
.qfb-body ul, .qfb-body ol { margin: 0 0 1rem; padding-left: 1.3rem; }
.qfb-body li { margin-bottom: .4rem; }
.qfb-body a { color: var(--b-blue); font-weight: 600; text-decoration: none; }
.qfb-body a:hover { text-decoration: underline; }
.qfb-body strong { color: var(--b-ink); }
.qfb-body blockquote {
    margin: 1.2rem 0; padding: .75rem 1rem; border-left: 3px solid var(--b-blue);
    background: var(--b-soft); border-radius: 0 8px 8px 0; color: var(--b-ink);
}
.qfb-body table { width: 100%; border-collapse: collapse; margin: 0 0 1.1rem; font-size: .88rem; }
.qfb-body th, .qfb-body td { border: 1px solid var(--b-line); padding: .45rem .6rem; text-align: left; }
.qfb-body th { background: var(--b-soft); color: var(--b-ink); }
.qfb-body img { max-width: 100%; height: auto; border-radius: 10px; }

.qfb-faq { margin-top: 2.4rem; }
.qfb-faq h2 { color: var(--b-ink); font-size: 1.25rem; margin: 0 0 .9rem; }
.qfb-faq details {
    background: var(--b-card); border: 1px solid var(--b-line); border-radius: 12px;
    padding: .85rem 1rem; margin-bottom: .55rem;
}
.qfb-faq summary { cursor: pointer; font-weight: 700; color: var(--b-ink); font-size: .92rem; }
.qfb-faq p { margin: .6rem 0 0; font-size: .9rem; }

.qfb-author {
    display: flex; gap: .9rem; align-items: center; margin: 2.4rem 0 1.2rem;
    background: var(--b-card); border: 1px solid var(--b-line); border-left: 4px solid var(--b-blue);
    border-radius: 14px; padding: 1rem 1.1rem; box-shadow: var(--b-shadow);
}
.qfb-author img {
    width: 54px; height: 54px; border-radius: 50%; object-fit: cover; flex: none;
    border: 2px solid var(--b-card); box-shadow: 0 0 0 2px var(--b-blue);
}
.qfb-author b { display: block; color: var(--b-ink); font-size: .92rem; line-height: 1.3; }
.qfb-author span { display: block; color: var(--b-muted); font-size: .78rem; }
.qfb-author a { color: var(--b-green); font-weight: 700; font-size: .82rem; text-decoration: none; }

.qfb-cta-box {
    margin: 2rem 0 0; padding: 1.3rem 1.2rem; border-radius: 14px;
    background: linear-gradient(135deg, var(--b-blue), var(--b-blue-dark));
    color: #fff; text-align: center;
}
.qfb-cta-box h2 { color: #fff; font-size: 1.2rem; margin: 0 0 .35rem; }
.qfb-cta-box p { margin: 0 0 .9rem; color: rgba(255,255,255,.9); font-size: .88rem; }
.qfb-cta-box .qfb-btn-primary { background: #fff; color: var(--b-blue-dark); }
.qfb-cta-box .qfb-btn-ghost { border-color: rgba(255,255,255,.6); color: #fff; }

.qfb-langs { display: flex; gap: .35rem; margin: .9rem 0 0; }
.qfb-langs a {
    font-size: .74rem; font-weight: 700; color: var(--b-muted); text-decoration: none;
    border: 1px solid var(--b-line); border-radius: 999px; padding: .2rem .6rem;
}
.qfb-langs a:hover { color: var(--b-blue); border-color: var(--b-blue); }
.qfb-langs .qfb-lang-on { color: #fff; background: var(--b-blue); border-color: var(--b-blue); }

/* The same pills in the header: no push-down margin, and they sit beside Sign in. */
.qfb-langs-nav { margin: 0; }

.qfb-related { margin-top: 2.6rem; }
.qfb-related h2 { color: var(--b-ink); font-size: 1.15rem; margin: 0 0 .9rem; }

.qfb-empty { padding: 2rem 0; color: var(--b-muted); }

.qfb-foot { border-top: 1px solid var(--b-line); padding: 1.7rem 0; font-size: .8rem; color: var(--b-muted); }
.qfb-foot-in { display: flex; flex-wrap: wrap; gap: .7rem 1.4rem; align-items: center; }
.qfb-foot a { color: var(--b-blue); text-decoration: none; font-weight: 600; }
.qfb-foot a:hover { text-decoration: underline; }

@media (max-width: 899px) {
    .qfb-links { display: none; }
    .qfb-menu { display: block; }
    .qfb-langs-nav { display: none; }
    .qfb-btn { padding: .45rem .75rem; }
}

/* A phone keeps the bar on one row: primary action and the arrow. Sign in lives in the menu. */
@media (max-width: 600px) {
    .qfb-cta .qfb-btn-ghost { display: none; }
    .qfb-nav-in { gap: .35rem .5rem; }
    .qfb-brand { font-size: .95rem; }
    .qfb-brand img { height: 26px; }
}

@media (min-width: 720px) {
    .qfb-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 900px) {
    .qfb-nav-in { flex-wrap: nowrap; }
    .qfb-links {
        order: 1; flex: 0 1 auto; flex-basis: auto;
        margin-left: 1.6rem; overflow: visible;
        padding-bottom: 0; margin-bottom: 0;
    }
    .qfb-cta { margin-left: auto; }
    .qfb-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

.qfb-video { margin: 0 0 1.6rem; }
.qfb-video iframe {
    width: 100%; aspect-ratio: 16 / 9; display: block;
    border: 1px solid var(--b-line); border-radius: 14px;
    background: #000; box-shadow: 0 10px 30px rgba(15, 23, 42, .18);
}
.qfb-video-note {
    margin: .55rem 0 0; font-size: .82rem; color: var(--b-ink-3, #64748b);
}
.qfb-video-note a { margin-left: .35rem; font-weight: 600; color: var(--b-blue); text-decoration: none; }
.qfb-video-note a:hover { text-decoration: underline; }