/* Smart MLM Engine page */
.eng-nav { position: sticky; top: 72px; z-index: 30; padding: 0.6rem 0; background: color-mix(in srgb, var(--bg-body) 88%, transparent); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); border-bottom: 1px solid var(--border-subtle); }
.eng-nav ul { display: flex; gap: 0.4rem; margin: 0; padding: 0; list-style: none; overflow-x: auto; scrollbar-width: none; }
.eng-nav ul::-webkit-scrollbar { display: none; }
.eng-nav a { display: block; padding: 0.4rem 0.85rem; border: 1px solid var(--border-subtle); border-radius: 999px; font: 500 0.8rem var(--font-body); white-space: nowrap; color: var(--text-secondary); transition: color .25s, border-color .25s, background .25s; }
.eng-nav a:hover { color: var(--text-primary); border-color: var(--sky); background: rgba(41, 171, 226, 0.08); }
.eng-nav a b { margin-right: 0.35rem; font: 600 0.7rem var(--font-mono); color: var(--sky); }

.eng-num { display: inline-block; margin-bottom: 0.6rem; font: 600 0.78rem var(--font-mono); letter-spacing: 0.14em; color: var(--sky); }
.eng-lead { max-width: 70ch; margin: 0 0 2rem; font-size: 1.05rem; }
.eng-sub { margin: 2.4rem 0 1rem; font-size: 1.25rem; }
.eng-sub small { display: block; margin-top: 0.2rem; font: 400 0.9rem var(--font-body); color: var(--text-secondary); }

/* flow */
.eng-flow { display: grid; grid-template-columns: repeat(var(--n, 6), 1fr); gap: 0.75rem; margin: 0; padding: 0; list-style: none; counter-reset: step; }
.eng-flow li { position: relative; padding: 1.1rem 1rem 1rem; border: 1px solid var(--border-subtle); border-radius: 18px; background: var(--bg-card); counter-increment: step; }
.eng-flow li::before { content: counter(step); display: grid; place-items: center; width: 28px; height: 28px; margin-bottom: 0.7rem; border-radius: 50%; background: rgba(41, 171, 226, 0.14); color: var(--sky); font: 600 0.8rem var(--font-mono); }
.eng-flow li:nth-child(4n+2)::before { background: rgba(18, 183, 106, 0.14); color: var(--emerald); }
.eng-flow li:nth-child(4n+3)::before { background: rgba(255, 164, 27, 0.15); color: var(--amber); }
.eng-flow li:nth-child(4n)::before { background: rgba(255, 77, 94, 0.14); color: var(--coral); }
.eng-flow li:not(:last-child)::after { content: "\2192"; position: absolute; right: -0.7rem; top: 1.2rem; z-index: 2; color: var(--text-tertiary); font-size: 0.9rem; }
.eng-flow strong { display: block; margin-bottom: 0.25rem; font-size: 0.98rem; }
.eng-flow span { display: block; font-size: 0.84rem; color: var(--text-secondary); line-height: 1.5; }

/* cards */
.eng-cards { display: grid; grid-template-columns: repeat(var(--c, 3), 1fr); gap: 1rem; }
.eng-card { padding: 1.4rem; border: 1px solid var(--border-subtle); border-radius: 20px; background: var(--bg-card); transition: border-color .3s, transform .4s var(--ease); }
.eng-card:hover { border-color: rgba(41, 171, 226, 0.5); transform: translateY(-3px); }
.eng-card > i, .eng-card > img { display: grid; place-items: center; width: 42px; height: 42px; margin-bottom: 0.9rem; border-radius: 12px; background: rgba(41, 171, 226, 0.12); color: var(--sky); object-fit: contain; }
.eng-card > img { background: none; width: 48px; height: 48px; }
.eng-card:nth-child(4n+2) > i { background: rgba(18, 183, 106, 0.12); color: var(--emerald); }
.eng-card:nth-child(4n+3) > i { background: rgba(255, 164, 27, 0.13); color: var(--amber); }
.eng-card:nth-child(4n) > i { background: rgba(255, 77, 94, 0.12); color: var(--coral); }
.eng-card h3 { margin: 0 0 0.4rem; font-size: 1.05rem; }
.eng-card p { margin: 0 0 0.7rem; font-size: 0.9rem; }
.eng-card ul { margin: 0; padding: 0; list-style: none; }
.eng-card li { position: relative; padding: 0.28rem 0 0.28rem 1.15rem; font-size: 0.87rem; color: var(--text-secondary); line-height: 1.5; }
.eng-card li::before { content: ""; position: absolute; left: 0; top: 0.78rem; width: 6px; height: 6px; border-radius: 50%; background: var(--emerald); }
.eng-card li b { color: var(--text-primary); font-weight: 600; }

/* chips */
.eng-chips { display: flex; flex-wrap: wrap; gap: 0.45rem; margin: 0; padding: 0; list-style: none; }
.eng-chips li { padding: 0.35rem 0.8rem; border: 1px solid var(--border-subtle); border-radius: 999px; background: var(--bg-card); font-size: 0.84rem; color: var(--text-secondary); }
.eng-chips li.on { border-color: rgba(18, 183, 106, 0.45); color: var(--text-primary); }

/* layers */
.eng-layers { display: grid; gap: 0.6rem; }
.eng-layer { display: grid; grid-template-columns: 150px 1fr; gap: 1rem; align-items: center; padding: 1rem 1.2rem; border: 1px solid var(--border-subtle); border-radius: 16px; background: var(--bg-card); }
.eng-layer strong { font: 600 0.78rem var(--font-mono); letter-spacing: 0.1em; text-transform: uppercase; color: var(--sky); }
.eng-layer:nth-child(2n) strong { color: var(--emerald); }
.eng-layer:nth-child(3n) strong { color: var(--amber); }
.eng-layer span { font-size: 0.92rem; color: var(--text-secondary); }

/* table helpers */
.eng-table { min-width: 900px; }
.eng-table td b { color: var(--text-primary); font-weight: 600; }
.eng-tag { display: inline-block; padding: 0.12rem 0.55rem; border-radius: 999px; font: 600 0.7rem var(--font-mono); letter-spacing: 0.04em; background: rgba(41, 171, 226, 0.13); color: var(--sky); white-space: nowrap; }
.eng-tag.g { background: rgba(18, 183, 106, 0.13); color: var(--emerald); }
.eng-tag.a { background: rgba(255, 164, 27, 0.14); color: var(--amber); }
.eng-tag.c { background: rgba(255, 77, 94, 0.13); color: var(--coral); }

/* split + example + simulator */
.eng-split { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(1.2rem, 3vw, 2.5rem); align-items: center; }
.eng-split img { width: 100%; height: auto; border-radius: 20px; }
.eng-sim { padding: 1.6rem; border: 1px solid var(--border-subtle); border-radius: 22px; background: var(--bg-card); }
.eng-sim-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.8rem; margin-bottom: 1.2rem; }
.eng-sim label { display: grid; gap: 0.3rem; font: 500 0.72rem var(--font-mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-tertiary); }
.eng-sim input { width: 100%; padding: 0.6rem 0.75rem; border: 1px solid var(--border-subtle); border-radius: 10px; background: var(--bg-body); color: var(--text-primary); font: 500 1rem var(--font-body); }
.eng-sim input:focus { outline: 2px solid var(--sky); outline-offset: 1px; }
.eng-sim-out { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0.8rem; }
.eng-sim-out div { padding: 0.9rem; border-radius: 14px; background: rgba(41, 171, 226, 0.07); }
.eng-sim-out div:last-child { background: rgba(18, 183, 106, 0.12); }
.eng-sim-out small { display: block; font: 500 0.7rem var(--font-mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-tertiary); }
.eng-sim-out b { display: block; margin-top: 0.2rem; font: 700 1.25rem var(--font-head, var(--font-body)); }
.eng-note { margin: 1rem 0 0; font-size: 0.82rem; color: var(--text-tertiary); }

@media (max-width: 1100px) {
  .eng-flow { grid-template-columns: repeat(3, 1fr); }
  .eng-flow li::after { display: none; }
  .eng-cards { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 720px) {
  .eng-flow, .eng-cards, .eng-split, .eng-sim-grid, .eng-sim-out { grid-template-columns: 1fr; }
  .eng-layer { grid-template-columns: 1fr; gap: 0.3rem; }
  .eng-nav { top: 60px; }
}

/* ---- polish: match casefile card language ---- */
.eng-card, .eng-flow li, .eng-layer, .eng-sim { background: linear-gradient(160deg, rgba(230,238,248,0.07), rgba(230,238,248,0.02)); box-shadow: var(--glass-edge, none); }
body.light-mode .eng-card, body.light-mode .eng-flow li, body.light-mode .eng-layer, body.light-mode .eng-sim { background: linear-gradient(160deg, rgba(255,255,255,0.95), rgba(255,255,255,0.65)); }
.eng-card { --tone: var(--sky); position: relative; overflow: hidden; border-radius: 24px; }
.eng-card:nth-child(4n+2) { --tone: var(--emerald); }
.eng-card:nth-child(4n+3) { --tone: var(--amber); }
.eng-card:nth-child(4n) { --tone: var(--coral); }
.eng-card::before { content: ""; position: absolute; inset: 0 0 auto 0; height: 90px; background: radial-gradient(circle at 20% 0%, color-mix(in srgb, var(--tone) 18%, transparent), transparent 70%); pointer-events: none; }
.eng-card > * { position: relative; }
.eng-card:hover { border-color: color-mix(in srgb, var(--tone) 45%, transparent); box-shadow: var(--glass-edge, none), 0 24px 60px -34px var(--tone); }
.eng-card li::before { background: var(--tone); }
.eng-card h3 { font-family: var(--font-head, inherit); letter-spacing: -0.01em; }
.eng-chips li { transition: border-color .25s, color .25s, transform .3s var(--ease); }
.eng-chips li:hover { border-color: var(--sky); color: var(--text-primary); transform: translateY(-2px); }
.eng-flow li { border-radius: 20px; }
.eng-layer { transition: border-color .3s, transform .35s var(--ease); }
.eng-layer:hover { border-color: rgba(41,171,226,.5); transform: translateX(4px); }
.eng-sim-out b { font-variant-numeric: tabular-nums; }
.eng-sim-out div:last-child b { color: var(--emerald); }
.eng-split img { border: 1px solid var(--border-subtle); box-shadow: 0 30px 70px -40px rgba(41,171,226,.6); }
.eng-note { max-width: 78ch; }
html { scroll-padding-top: 130px; }
@media (prefers-reduced-motion: reduce) { .eng-card, .eng-layer, .eng-chips li { transition: none; } .eng-card:hover, .eng-layer:hover, .eng-chips li:hover { transform: none; } }