.rseo-wrap {
    --rseo-ink: #17202a;
    --rseo-muted: #58636f;
    --rseo-line: rgba(23, 32, 42, .14);
    --rseo-paper: #f7f6f2;
    --rseo-accent: #236b5e;
    background: var(--rseo-paper);
    color: var(--rseo-ink);
    padding: clamp(4rem, 8vw, 7rem) 1.25rem;
}
.rseo-shell {
    box-sizing: border-box;
    margin: 0 auto;
    max-width: 1160px;
}
.rseo-wrap * { box-sizing: border-box; }
.rseo-intro { max-width: 850px; }
.rseo-kicker {
    color: var(--rseo-accent);
    font-size: .78rem;
    font-weight: 800;
    letter-spacing: .14em;
    margin: 0 0 .75rem;
    text-transform: uppercase;
}
.rseo-intro h2,
.rseo-section-head h2 {
    color: var(--rseo-ink);
    font-size: clamp(1.8rem, 4vw, 3rem);
    letter-spacing: -.035em;
    line-height: 1.08;
    margin: 0;
}
.rseo-intro > p:last-child,
.rseo-section-head > p:last-child {
    color: var(--rseo-muted);
    font-size: 1.05rem;
    line-height: 1.75;
    margin: 1.25rem 0 0;
    max-width: 760px;
}
.rseo-guide {
    display: grid;
    gap: 1px;
    grid-template-columns: repeat(3, 1fr);
    margin: 2.75rem 0 5rem;
    overflow: hidden;
    border: 1px solid var(--rseo-line);
    border-radius: 1rem;
    background: var(--rseo-line);
}
.rseo-guide article {
    background: #fff;
    padding: clamp(1.4rem, 3vw, 2rem);
}
.rseo-guide span {
    color: var(--rseo-accent);
    font-size: .75rem;
    font-weight: 800;
    letter-spacing: .12em;
}
.rseo-guide h3 {
    color: var(--rseo-ink);
    font-size: 1.15rem;
    margin: .7rem 0 .55rem;
}
.rseo-guide p,
.rseo-term-grid dd,
.rseo-faq-list p,
.rseo-note p {
    color: var(--rseo-muted);
    line-height: 1.7;
    margin: 0;
}
.rseo-glossary { scroll-margin-top: 2rem; }
.rseo-term-grid {
    display: grid;
    gap: 1rem;
    grid-template-columns: repeat(2, 1fr);
    margin: 2rem 0 5rem;
}
.rseo-term-grid > div {
    background: #fff;
    border: 1px solid var(--rseo-line);
    border-radius: .85rem;
    padding: 1.5rem;
    scroll-margin-top: 2rem;
}
.rseo-term-grid dt {
    color: var(--rseo-ink);
    font-size: 1.05rem;
    font-weight: 800;
    margin-bottom: .55rem;
}
.rseo-term-grid dd { margin: 0; }
.rseo-faq-list {
    border-top: 1px solid var(--rseo-line);
    margin-top: 2rem;
}
.rseo-faq-list details {
    border-bottom: 1px solid var(--rseo-line);
    margin: 0;
    padding: 0;
}
.rseo-faq-list summary {
    color: var(--rseo-ink);
    cursor: pointer;
    font-size: 1.08rem;
    font-weight: 750;
    list-style-position: outside;
    padding: 1.25rem .25rem;
}
.rseo-faq-list details p {
    max-width: 850px;
    padding: 0 .25rem 1.4rem;
}
.rseo-note {
    background: #fff;
    border-left: 4px solid var(--rseo-accent);
    border-radius: .25rem .85rem .85rem .25rem;
    display: grid;
    gap: .4rem;
    margin-top: 3rem;
    padding: 1.35rem 1.5rem;
}
.rseo-note strong { color: var(--rseo-ink); }
@media (max-width: 760px) {
    .rseo-guide,
    .rseo-term-grid { grid-template-columns: 1fr; }
    .rseo-guide { gap: 1px; }
}
@media (prefers-color-scheme: dark) {
    .rseo-wrap {
        --rseo-ink: #f2f5f4;
        --rseo-muted: #c1cbc8;
        --rseo-line: rgba(255, 255, 255, .13);
        --rseo-paper: #111817;
        --rseo-accent: #73c7b4;
    }
    .rseo-guide article,
    .rseo-term-grid > div,
    .rseo-note { background: #182220; }
}