/* ---------- Hero ---------- */
.hero { padding: clamp(40px, 6vw, 88px) 0 clamp(72px, 8vw, 120px); position: relative; }
.hero::before { /* drawing-paper grid, faded out at the edges */
  content: ""; position: absolute; inset: 0 0 auto 0; height: 100%; pointer-events: none; z-index: -1;
  background-image: linear-gradient(var(--scrim) 1px, transparent 1px), linear-gradient(90deg, var(--scrim) 1px, transparent 1px);
  background-size: 32px 32px; -webkit-mask-image: radial-gradient(120% 80% at 70% 30%, #000 30%, transparent 75%); mask-image: radial-gradient(120% 80% at 70% 30%, #000 30%, transparent 75%);
}
.hero-grid { display: grid; grid-template-columns: minmax(0, 520px) minmax(0, 1fr); gap: clamp(32px, 4.5vw, 72px); align-items: center; }
.hero-copy { display: grid; gap: 26px; align-content: start; padding-top: 8px; min-width: 0; }
.hero-copy .h1 { font-size: clamp(44px, 4.9vw, 72px); }
.hero-proof { display: grid; grid-template-columns: repeat(3, auto); justify-content: start; gap: 0 32px; margin: 10px 0 0; padding-top: 22px; border-top: 1px solid var(--rule); }
.hero-proof dt { white-space: nowrap; font: 500 11px/1.3 var(--font-mono); letter-spacing: .07em; text-transform: uppercase; color: var(--ink-3); }
.hero-proof dd { margin: 8px 0 0; font-family: var(--font-display); font-size: 30px; line-height: 1; letter-spacing: -0.02em; font-weight: 400; }
.hero-proof dd .link { background-size: 100% 1.5px; padding-bottom: 3px; }
.sample-note { position: absolute; right: 4px; bottom: -32px; font: 12px/1.4 var(--font-mono); color: var(--ink-3); }
.hero-visual { position: relative; margin-right: calc(-1 * min(var(--gutter), 40px)); }

/* Shared section patterns (both pages): drawing + timeline, FAQ, close, bands. */

/* ---------- Mechanism ---------- */
.mech-grid { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); gap: clamp(28px, 4vw, 64px); align-items: center; }
.mech-drawing { margin: 0; padding: clamp(18px, 2.4vw, 36px); background: var(--sheet); border-radius: var(--r-xl); box-shadow: var(--sh-2); background-image: linear-gradient(var(--scrim) 1px, transparent 1px), linear-gradient(90deg, var(--scrim) 1px, transparent 1px); background-size: 20px 20px; }
.mech-drawing .drawing .lyr { transition: none; }
.timeline { display: grid; gap: 0; position: relative; padding-left: 28px; }
.timeline::before { content: ""; position: absolute; left: 6px; top: 8px; bottom: 8px; width: 2px; background: var(--rule); border-radius: 2px; }
.timeline::after { content: ""; position: absolute; left: 6px; top: 8px; width: 2px; height: calc((100% - 16px) * var(--tp, 0)); background: var(--red); border-radius: 2px; }
.timeline li { position: relative; padding: 14px 0 22px; opacity: .4; transition: opacity var(--dur-enter) var(--ease-out); }
.timeline li::before { content: ""; position: absolute; left: -27px; top: 18px; width: 12px; height: 12px; border-radius: 50%; background: var(--paper); box-shadow: inset 0 0 0 2px var(--rule-2); transition: box-shadow var(--dur-quick), background-color var(--dur-quick); }
.timeline li.on { opacity: 1; }
.timeline li.on::before { background: var(--red); box-shadow: 0 0 0 4px var(--red-wash); }
.timeline .mono { display: block; font-size: 12px; color: var(--ink-3); margin-bottom: 4px; }
.timeline b { display: block; font-weight: 500; font-size: 17px; }
.timeline p { color: var(--ink-2); font-size: 15px; margin-top: 2px; }


/* ---------- FAQ ---------- */
.faq-grid { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: clamp(32px, 6vw, 96px); align-items: start; }
.faq-grid .section-head { position: sticky; top: 120px; }
.faq-list details { border-top: 1px solid var(--rule); }
.faq-list details:last-child { border-bottom: 1px solid var(--rule); }
.faq-list summary { list-style: none; cursor: pointer; padding: 20px 36px 20px 0; font-size: 17px; font-weight: 500; position: relative; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: ""; position: absolute; right: 4px; top: 50%; width: 12px; height: 12px; margin-top: -6px;
  background: linear-gradient(var(--ink-2), var(--ink-2)) center / 12px 1.5px no-repeat, linear-gradient(var(--ink-2), var(--ink-2)) center / 1.5px 12px no-repeat; transition: transform var(--dur-quick) var(--ease-out); }
.faq-list details[open] summary::after { transform: rotate(45deg); }
.faq-list details p { padding: 0 36px 22px 0; color: var(--ink-2); max-width: 62ch; }

/* ---------- Close ---------- */
.close { padding: clamp(90px, 11vw, 170px) 0; text-align: center; border-top: 1px solid var(--rule); position: relative; overflow: hidden; }
.close-inner { display: grid; gap: 22px; justify-items: center; }
.close .h2 { max-width: 16ch; }
.close .btn-row { justify-content: center; }


.theme-band { background: var(--paper-2); }

@media (max-width: 900px) {
  .mech-grid, .faq-grid { grid-template-columns: 1fr; }
  .faq-grid .section-head { position: static; }
}

@media (max-width: 1100px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-copy { max-width: 640px; }
  .hero-visual { margin-right: 0; margin-top: 24px; }
}
@media (max-width: 640px) {
  .hero-proof { grid-template-columns: 1fr 1fr; gap: 18px 24px; }
  .hero-proof > div:last-child { grid-column: 1 / -1; }
  .sample-note { position: static; margin-top: 10px; }
  .hero-visual { margin-top: 8px; }
}