:root {
    color-scheme: dark;
    --seo-bg: #061225;
    --seo-panel: rgba(15, 31, 56, 0.88);
    --seo-panel-soft: rgba(24, 47, 82, 0.62);
    --seo-border: rgba(109, 165, 255, 0.28);
    --seo-text: #f3f7ff;
    --seo-muted: #b5c3d8;
    --seo-blue: #61a7ff;
    --seo-green: #6fe2b0;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    min-width: 320px;
    color: var(--seo-text);
    background:
        linear-gradient(180deg, rgba(3, 12, 27, 0.68), var(--seo-bg) 42rem),
        url("assets/landing-hero-night-runway.webp") center top / min(100%, 1200px) auto no-repeat,
        var(--seo-bg);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    line-height: 1.6;
}

a { color: inherit; }

.seo-shell {
    width: min(1120px, calc(100% - 36px));
    margin: 0 auto;
}

.seo-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 22px 0;
}

.seo-brand {
    color: var(--seo-text);
    font-size: 1.05rem;
    font-weight: 800;
    letter-spacing: 0.22em;
    text-decoration: none;
}

.seo-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 8px 18px;
    color: var(--seo-muted);
    font-size: 0.9rem;
}

.seo-nav a:hover,
.seo-footer a:hover { color: var(--seo-text); }

.seo-hero {
    max-width: 820px;
    padding: 74px 0 56px;
}

.seo-kicker {
    margin: 0 0 12px;
    color: var(--seo-green);
    font-size: 0.8rem;
    font-weight: 800;
    letter-spacing: 0.18em;
    text-transform: uppercase;
}

h1, h2, h3 { line-height: 1.15; }

h1 {
    max-width: 800px;
    margin: 0;
    font-size: clamp(2.35rem, 6vw, 4.8rem);
    letter-spacing: -0.04em;
}

.seo-lede {
    max-width: 720px;
    margin: 24px 0 0;
    color: var(--seo-muted);
    font-size: clamp(1.05rem, 2vw, 1.25rem);
}

.seo-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 30px;
}

.seo-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 11px 19px;
    border: 1px solid var(--seo-blue);
    border-radius: 999px;
    background: #2f7ff1;
    color: white;
    font-weight: 800;
    text-decoration: none;
}

.seo-button.secondary {
    border-color: var(--seo-border);
    background: rgba(8, 19, 37, 0.72);
}

.seo-section {
    padding: 36px 0;
    border-top: 1px solid rgba(148, 184, 231, 0.14);
}

.seo-section h2 {
    margin: 0 0 12px;
    font-size: clamp(1.65rem, 3vw, 2.35rem);
}

.seo-section > p {
    max-width: 760px;
    color: var(--seo-muted);
}

.seo-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
    margin-top: 24px;
}

.seo-card {
    padding: 22px;
    border: 1px solid var(--seo-border);
    border-radius: 18px;
    background: var(--seo-panel);
}

.seo-card h3 { margin: 0 0 9px; font-size: 1.1rem; }
.seo-card p { margin: 0; color: var(--seo-muted); font-size: 0.96rem; }

.seo-subjects {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 22px;
}

.seo-subjects span {
    padding: 8px 13px;
    border: 1px solid rgba(111, 226, 176, 0.28);
    border-radius: 999px;
    background: var(--seo-panel-soft);
    color: #d9ffed;
    font-size: 0.92rem;
}

.seo-faq { margin-top: 20px; }
.seo-faq details {
    padding: 16px 0;
    border-bottom: 1px solid rgba(148, 184, 231, 0.14);
}
.seo-faq summary { cursor: pointer; font-weight: 750; }
.seo-faq p { max-width: 760px; margin: 10px 0 0; color: var(--seo-muted); }

.seo-note {
    margin-top: 22px;
    padding: 16px 18px;
    border-left: 3px solid var(--seo-green);
    background: rgba(111, 226, 176, 0.08);
    color: var(--seo-muted);
}

.seo-footer {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 12px 24px;
    padding: 34px 0 42px;
    color: var(--seo-muted);
    font-size: 0.88rem;
}

.seo-footer nav { display: flex; flex-wrap: wrap; gap: 8px 16px; }

@media (max-width: 720px) {
    .seo-shell { width: min(100% - 28px, 620px); }
    .seo-header { align-items: flex-start; flex-direction: column; }
    .seo-nav { justify-content: flex-start; }
    .seo-hero { padding: 48px 0 40px; }
    .seo-grid { grid-template-columns: 1fr; }
    .seo-footer { flex-direction: column; }
}