/* Discover — the deck as a scroll story. */
.discover-page { background: var(--bg); }
.discover-page .site-header { position: fixed; left: 0; right: 0; color: #fff; }
.discover-page .site-header:not(.is-condensed) .site-nav a { color: rgba(226, 238, 255, .82); }
.discover-page .site-header:not(.is-condensed) .site-nav a[aria-current="page"] { color: #fff; background: rgba(255, 255, 255, .12); }
.discover-page .site-header:not(.is-condensed) :is(.language-button, .theme-toggle, .account-trigger, .icon-button) {
  border-color: rgba(214, 234, 255, .26); background: rgba(10, 26, 52, .35); color: #fff;
}
.discover-page .site-header:not(.is-condensed) .language-button::before { background: #fff; }
.discover-page .site-header:not(.is-condensed) .language-button span { color: rgba(226, 238, 255, .75); }
.discover-page .site-header:not(.is-condensed) .language-button[data-lang="en"] span:first-child,
.discover-page .site-header:not(.is-condensed) .language-button[data-lang="zh"] span:last-child { color: var(--navy); }
.discover-page .site-header:not(.is-condensed) .logo-day { display: none; }
.discover-page .site-header:not(.is-condensed) .logo-night { display: block; }
.discover-page .site-header.is-condensed { color: var(--ink); }

/* ---------- Sky hero ---------- */
.sky-hero {
  position: relative; isolation: isolate; display: grid; align-items: center; min-height: 100svh; overflow: hidden;
  padding: calc(var(--header-h) + 2rem) var(--gutter) 6rem; color: #fff; background: #040b17;
}
.sky { position: absolute; inset: 0; z-index: -1; }
.sky::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(120% 80% at 70% 0%, #11294d 0%, #071428 45%, #030912 100%);
}
.sky-stars {
  position: absolute; inset: 0; opacity: .7;
  background-image:
    radial-gradient(1.2px 1.2px at 12% 22%, #fff 50%, transparent 51%), radial-gradient(1px 1px at 28% 12%, #cfe3ff 50%, transparent 51%),
    radial-gradient(1.4px 1.4px at 44% 30%, #fff 50%, transparent 51%), radial-gradient(1px 1px at 63% 18%, #fff 50%, transparent 51%),
    radial-gradient(1.2px 1.2px at 78% 8%, #cfe3ff 50%, transparent 51%), radial-gradient(1px 1px at 88% 34%, #fff 50%, transparent 51%),
    radial-gradient(1px 1px at 6% 48%, #fff 50%, transparent 51%), radial-gradient(1.3px 1.3px at 34% 52%, #cfe3ff 50%, transparent 51%),
    radial-gradient(1px 1px at 56% 44%, #fff 50%, transparent 51%), radial-gradient(1px 1px at 94% 56%, #fff 50%, transparent 51%);
}
html.motion-ok .sky-stars { animation: stars-breathe 7s ease-in-out infinite alternate; }
@keyframes stars-breathe { to { opacity: .35; } }
.sky-arcs { position: absolute; inset: 0; width: 100%; height: 100%; }
.sky-arc { fill: none; stroke: url(#sky-arc); stroke-width: 1.4; stroke-linecap: round; stroke-dasharray: 1; stroke-dashoffset: 0; opacity: .55; }
.sky-arc-main { stroke-width: 2.2; opacity: 1; filter: drop-shadow(0 0 6px rgba(156, 199, 255, .8)); }
.sky-arc-dashed { stroke-dasharray: .006 .014; opacity: .45; }
.sky-nodes circle { fill: #fff; filter: drop-shadow(0 0 6px #9cc7ff); }
html.motion-ok .sky-nodes circle { animation: node-blink 3.6s ease-in-out infinite; transform-box: fill-box; transform-origin: center; }
html.motion-ok .sky-nodes circle:nth-child(3n) { animation-delay: 1.2s; }
html.motion-ok .sky-nodes circle:nth-child(3n+1) { animation-delay: 2.1s; }
@keyframes node-blink { 50% { opacity: .35; transform: scale(.7); } }
.sky-earth {
  --earth: max(180vw, 2200px);
  position: absolute; left: 50%; top: 74%; width: var(--earth); height: var(--earth); margin-left: calc(var(--earth) / -2); border-radius: 50%;
  background: radial-gradient(60% 45% at 30% 2%, rgba(255, 220, 180, .55), transparent 60%), radial-gradient(closest-side, #0d2547 0%, #081a33 70%, #061428 100%);
  box-shadow: 0 -2px 0 rgba(190, 220, 255, .85), 0 -20px 60px rgba(120, 175, 255, .55), 0 -80px 160px rgba(60, 120, 230, .35);
}
.sky-copy { position: relative; width: min(1200px, 100%); margin: 0 auto; }
.sky-copy .eyebrow { color: #cfe3ff; }
.sky-copy .eyebrow .star-mark { color: #9cc7ff; }
.sky-title { font-size: clamp(3.2rem, 8.6vw, 8rem); line-height: .95; letter-spacing: -.05em; }
.sky-title .line { display: block; overflow: hidden; padding: 0 .06em .08em; margin: 0 -.06em -.08em; }
.sky-title .line-inner { display: inline-block; }
.sky-title .line + .line .line-inner { color: #9cc7ff; }
html[lang="zh-CN"] .sky-title { font-size: clamp(2.8rem, 7vw, 6.2rem); line-height: 1.12; letter-spacing: .02em; }
.sky-lead { max-width: 30ch; margin: 1.6rem 0 2.2rem; color: rgba(226, 238, 255, .86); font-size: clamp(1.1rem, 2vw, 1.45rem); line-height: 1.45; }
.sky-actions { display: flex; flex-wrap: wrap; gap: .75rem; }
.sky-ghost { --button-bg: rgba(255, 255, 255, .08); --button-ink: #fff; box-shadow: inset 0 0 0 1px rgba(214, 234, 255, .35); }
.scroll-cue { position: absolute; left: 50%; bottom: 2rem; width: 26px; height: 42px; margin-left: -13px; border: 1.5px solid rgba(214, 234, 255, .5); border-radius: 14px; }
.scroll-cue span { position: absolute; left: 50%; top: 8px; width: 4px; height: 8px; margin-left: -2px; border-radius: 2px; background: #fff; }
html.motion-ok .scroll-cue span { animation: cue 2s var(--ease-in-out) infinite; }
@keyframes cue { 0% { transform: translateY(0); opacity: 0; } 30% { opacity: 1; } 100% { transform: translateY(16px); opacity: 0; } }

/* ---------- Chapters ---------- */
.chapter { position: relative; width: min(1240px, calc(100% - 2 * var(--gutter))); margin: 0 auto; padding: clamp(3.5rem, 9vh, 6.5rem) 0; }
.chapter h2 { font-size: var(--fs-2xl); letter-spacing: -.035em; }
.chapter-copy > p:not(.chapter-label):not(.decision-count), .chapter-head > p:not(.chapter-label) { max-width: 52ch; margin-top: 1.1rem; color: var(--ink-2); font-size: var(--fs-md); line-height: 1.6; }
.chapter-label { margin-bottom: 1rem; color: var(--accent-ink); font-size: var(--fs-sm); font-weight: 650; }
.chapter-note { display: block; max-width: 56ch; margin-top: 1.4rem; color: var(--ink-3); font-size: var(--fs-xs); }
.chapter-head { max-width: 760px; margin-bottom: clamp(2.2rem, 5vh, 3.6rem); }

/* Journey */
.journey-chapter { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(2rem, 6vw, 6rem); align-items: center; }
.decision-count { display: flex; align-items: baseline; gap: .2rem; margin-top: 2rem; }
.decision-count b { font-size: clamp(3.4rem, 7vw, 5.4rem); font-weight: 650; letter-spacing: -.04em; line-height: 1; color: var(--accent); font-variant-numeric: tabular-nums; }
.decision-count span { color: var(--ink-2); font-size: var(--fs-md); font-weight: 560; }
.journey-track { position: relative; }
.journey-stops { position: relative; display: grid; gap: 0; margin: 0; padding: 0; list-style: none; }
.journey-stops li {
  position: relative; display: grid; gap: .2rem; padding: 1.3rem 1.4rem 1.3rem 3.6rem; margin-bottom: .8rem;
  border: 1px solid var(--line); border-radius: var(--r-lg); background: var(--surface); box-shadow: var(--shadow-1);
  transition: border-color var(--d-ui) var(--ease-out), box-shadow var(--d-ui) var(--ease-out), transform var(--d-ui) var(--ease-out);
}
.journey-stops li strong { font-size: var(--fs-lg); letter-spacing: -.02em; }
.journey-stops li > span:not(.stop-dot) { color: var(--ink-3); font-size: var(--fs-sm); }
.stop-dot {
  position: absolute; left: 1.35rem; top: 1.75rem; width: 14px; height: 14px; border-radius: 50%; border: 2px solid var(--line-strong); background: var(--surface);
  transition: background-color var(--d-ui) var(--ease-out), border-color var(--d-ui) var(--ease-out), box-shadow var(--d-ui) var(--ease-out);
}
.journey-stops li.is-active { border-color: color-mix(in srgb, var(--accent) 40%, var(--line)); box-shadow: var(--shadow-2); transform: translateX(-6px); }
.journey-stops li.is-active .stop-dot { border-color: var(--accent); background: var(--accent); box-shadow: 0 0 0 5px var(--accent-tint); }
.stops-line { position: absolute; z-index: 0; left: calc(1.35rem + 6px); top: 2.2rem; bottom: 3rem; width: 2px; background: var(--line); pointer-events: none; }
.stops-fill { display: block; width: 100%; height: 100%; background: var(--accent); transform: scaleY(var(--journey, 1)); transform-origin: top; }
.journey-stops .stop-dot { z-index: 2; }

/* Gaps */
.providers { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: clamp(.6rem, 2.4vw, 2.2rem); position: relative; }
.provider {
  position: relative; z-index: 1; display: grid; place-items: center; min-height: 92px; padding: 1rem; border: 1px solid var(--line); border-radius: var(--r-lg);
  background: var(--surface); font-weight: 650; text-align: center; box-shadow: var(--shadow-1);
}
.gap { display: none; }
.providers::before {
  content: ""; position: absolute; left: 6%; right: 6%; top: 50%; height: 2px;
  background: repeating-linear-gradient(90deg, var(--danger) 0 6px, transparent 6px 14px); opacity: var(--gap-opacity, .6);
}
.providers::after {
  content: ""; position: absolute; left: 6%; right: 6%; top: 50%; height: 2px; background: var(--accent);
  transform: scaleX(var(--closed, 1)); transform-origin: left;
}
.operating-layer {
  display: grid; gap: .3rem; justify-items: center; margin: 2.2rem auto 0; width: min(640px, 100%); padding: 1.6rem 2rem; text-align: center;
  border-radius: var(--r-xl); background: var(--navy); color: #fff; box-shadow: var(--shadow-3);
}
.operating-layer strong { font-size: var(--fs-lg); letter-spacing: -.02em; }
.operating-layer span { color: rgba(214, 232, 255, .8); font-size: var(--fs-sm); }
html[data-theme="dark"] .operating-layer { background: var(--surface-3); }

/* Intent */
.intent-chapter { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); gap: clamp(2rem, 6vw, 5rem); align-items: center; }
.intent-demo { display: grid; gap: .8rem; }
.intent-request { padding: 1.4rem 1.5rem; border: 1px solid var(--line); border-radius: var(--r-xl); background: var(--surface); box-shadow: var(--shadow-2); }
.intent-tag { color: var(--accent-ink); font-size: var(--fs-xs); font-weight: 650; }
.intent-quote { margin-top: .5rem; min-height: 3.1em; font-size: clamp(1.1rem, 1.8vw, 1.35rem); font-weight: 560; line-height: 1.45; letter-spacing: -.01em; }
.intent-quote.is-typing::after { content: ""; display: inline-block; width: 2px; height: 1.1em; margin-left: 2px; vertical-align: -.15em; background: var(--accent); animation: caret 900ms steps(1) infinite; }
@keyframes caret { 50% { opacity: 0; } }
.intent-layer { display: grid; grid-template-columns: auto 1fr; gap: 1rem; align-items: start; padding: 1.1rem 1.3rem; border: 1px solid var(--line); border-radius: var(--r-lg); background: var(--surface); }
.intent-layer strong { display: block; font-size: var(--fs-sm); }
.intent-layer span:not(.layer-index):not(.constraint) { color: var(--ink-3); font-size: var(--fs-sm); }
.layer-index { display: grid; place-items: center; width: 34px; height: 30px; border-radius: var(--r-pill); background: var(--accent); color: #fff; font-size: var(--fs-xs); font-weight: 700; }
.constraint-row { display: flex; flex-wrap: wrap; gap: .4rem; margin-top: .6rem; }
.constraint { padding: .3rem .7rem; border-radius: var(--r-pill); background: var(--accent-soft); color: var(--accent-ink); font-size: var(--fs-xs); font-weight: 650; }
.intent-result { display: flex; gap: .9rem; align-items: center; padding: 1.1rem 1.3rem; border-radius: var(--r-lg); background: var(--navy); color: #fff; }
.intent-result .star-mark { width: 22px; height: 22px; color: #9cc7ff; }
.intent-result strong { display: block; }
.intent-result span { color: rgba(214, 232, 255, .8); font-size: var(--fs-sm); }
html[data-theme="dark"] .intent-result { background: var(--surface-3); }

/* Smart luxury */
.cabin-compare { display: grid; grid-template-columns: 1fr 1fr 1.3fr; gap: 1rem; align-items: stretch; }
.cabin { position: relative; display: grid; align-content: end; gap: .6rem; min-height: 260px; padding: 1.5rem; border: 1px solid var(--line); border-radius: var(--r-xl); background: var(--surface); overflow: hidden; }
.cabin-kicker { font-size: var(--fs-lg); font-weight: 650; letter-spacing: -.02em; }
.cabin p { color: var(--ink-3); font-size: var(--fs-sm); }
.cabin-altier { min-height: 340px; color: #fff; border: 0; background: var(--navy); box-shadow: var(--shadow-3); }
.cabin-altier img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: .6; transform: scale(1.08); transition: transform 2.4s var(--ease-out); }
.cabin-altier.is-in img { transform: scale(1); }
.cabin-altier::after { content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, transparent 20%, rgba(4, 14, 30, .9)); }
.cabin-altier > :not(img) { position: relative; z-index: 1; }
.cabin-altier p { color: rgba(226, 238, 255, .85); }
.cabin-altier .pill { position: absolute; top: 1.2rem; left: 1.2rem; background: var(--accent); color: #fff; }
.credit-math { display: grid; gap: .2rem; width: min(560px, 100%); margin: 2.4rem 0 0 auto; padding: 1.4rem 1.6rem; border-radius: var(--r-xl); background: var(--surface); border: 1px solid var(--line); box-shadow: var(--shadow-2); }
.credit-row { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; padding: .55rem 0; border-bottom: 1px solid var(--line); }
.credit-row span { color: var(--ink-2); font-size: var(--fs-sm); }
.credit-row b { font-size: 1.5rem; font-weight: 650; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.credit-minus b { color: var(--accent); }
.credit-total { border-bottom: 0; }
.credit-total b { font-size: 2.1rem; }
.credit-math small { color: var(--ink-3); font-size: var(--fs-xs); }

/* Disruption */
.disruption-chapter { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr); gap: clamp(2rem, 6vw, 5rem); align-items: center; }
.disruption-photo { position: relative; margin: 0; }
.disruption-photo img { width: 100%; height: auto; aspect-ratio: 5 / 4; object-fit: cover; border-radius: var(--r-xl); filter: grayscale(1) contrast(1.05); }
.delay-card {
  position: absolute; left: clamp(1rem, 4vw, 2rem); right: clamp(1rem, 4vw, 2rem); bottom: clamp(1rem, 4vw, 2rem); padding: 1.3rem 1.4rem;
  border-radius: var(--r-xl); background: var(--glass-strong); color: var(--ink); box-shadow: var(--shadow-3);
  backdrop-filter: blur(22px) saturate(1.4); -webkit-backdrop-filter: blur(22px) saturate(1.4);
}
.delay-number { display: flex; align-items: baseline; gap: .5rem; }
.delay-number b { color: var(--accent); font-size: 3rem; font-weight: 650; line-height: 1; letter-spacing: -.03em; font-variant-numeric: tabular-nums; }
.delay-number span { color: var(--ink-3); }
.delay-copy { margin-top: .6rem; color: var(--ink-2); }
.delay-copy strong { display: block; color: var(--ink); }
.delay-steps { display: grid; gap: .35rem; margin: 1rem 0 0; padding: 0; list-style: none; }
.delay-steps li { display: flex; align-items: center; gap: .55rem; color: var(--success); font-size: var(--fs-sm); font-weight: 650; }
.delay-steps li::before { content: ""; width: 16px; height: 16px; border-radius: 50%; background: var(--success) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none' stroke='white' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m4.5 8.2 2.3 2.3 4.7-5'/%3E%3C/svg%3E") center / 100% no-repeat; }
.milestones { position: relative; display: grid; grid-template-columns: repeat(4, 1fr); gap: .5rem; margin-top: 2rem; padding-top: 1.4rem; }
.milestones span { position: relative; color: var(--ink-3); font-size: var(--fs-xs); font-weight: 600; }
.milestones span::before { content: ""; position: absolute; top: -1.4rem; left: 0; width: 12px; height: 12px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 4px var(--accent-tint); }
.milestones::before { content: ""; position: absolute; top: 5px; left: 0; right: 0; height: 2px; background: var(--line); }
.milestone-progress { position: absolute; top: 5px; left: 0; right: 0; height: 2px; background: var(--accent); transform: scaleX(var(--milestone, .62)); transform-origin: left; }

/* Principles */
.principles { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; }
.principles article { padding: 1.5rem; border: 1px solid var(--line); border-radius: var(--r-xl); background: var(--surface); }
.principles span { color: var(--accent-ink); font-size: var(--fs-xs); font-weight: 700; }
.principles h3 { margin: .8rem 0 .5rem; font-size: var(--fs-md); letter-spacing: -.015em; line-height: 1.25; }
.principles p { color: var(--ink-3); font-size: var(--fs-sm); }
.beachhead { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem 2rem; margin-top: clamp(3rem, 8vh, 5rem); padding-top: 2.4rem; border-top: 1px solid var(--line); }
.beachhead div { display: grid; gap: .3rem; }
.beachhead b { font-size: clamp(2.2rem, 4.4vw, 3.4rem); font-weight: 650; letter-spacing: -.035em; line-height: 1; font-variant-numeric: tabular-nums; }
.beachhead span { color: var(--ink-3); font-size: var(--fs-sm); }
.beachhead small { grid-column: 1 / -1; color: var(--ink-3); font-size: var(--fs-xs); }

/* FAQ */
.faq-list { display: grid; gap: .6rem; max-width: 880px; }
.faq-list details { border: 1px solid var(--line); border-radius: var(--r-lg); background: var(--surface); overflow: hidden; }
.faq-list summary { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1.2rem 1.4rem; font-weight: 600; cursor: pointer; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: ""; flex: 0 0 12px; width: 12px; height: 12px; border-right: 2px solid var(--ink-3); border-bottom: 2px solid var(--ink-3); transform: rotate(45deg) translate(-3px, -3px); transition: transform var(--d-ui) var(--ease-out); }
.faq-list details[open] summary::after { transform: rotate(225deg) translate(-3px, -3px); }
.faq-list details > div { padding: 0 1.4rem 1.3rem; color: var(--ink-2); }
.faq-list details::details-content { block-size: 0; overflow: hidden; transition: block-size var(--d-ui) var(--ease-out), content-visibility var(--d-ui) allow-discrete; }
.faq-list details[open]::details-content { block-size: auto; }
@supports (interpolate-size: allow-keywords) { .faq-list { interpolate-size: allow-keywords; } }

/* Final */
.final-chapter {
  position: relative; isolation: isolate; display: grid; justify-items: center; gap: 2rem; margin: clamp(2rem, 6vh, 4rem) clamp(10px, 1.6vw, 24px) 0;
  padding: clamp(5rem, 14vh, 9rem) var(--gutter); border-radius: clamp(18px, 2.2vw, 30px); overflow: hidden; text-align: center; color: #fff;
  background: radial-gradient(90% 120% at 50% 0%, #143364, #061226 70%);
}
.final-arc { position: absolute; inset: auto 0 0; z-index: -1; width: 100%; height: 70%; }
.final-arc path { fill: none; stroke: rgba(156, 199, 255, .6); stroke-width: 1.5; stroke-dasharray: 1; stroke-dashoffset: 0; vector-effect: non-scaling-stroke; }
.final-chapter h2 { font-size: clamp(2.4rem, 5.6vw, 4.8rem); letter-spacing: -.045em; line-height: 1.02; }
.final-chapter h2 span { display: block; }
.final-chapter h2 span + span { color: #9cc7ff; }
html[lang="zh-CN"] .final-chapter h2 { letter-spacing: .01em; line-height: 1.2; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .journey-chapter, .intent-chapter, .disruption-chapter { grid-template-columns: 1fr; }
  .cabin-compare { grid-template-columns: 1fr; }
  .principles { grid-template-columns: 1fr 1fr; }
  .providers { grid-template-columns: 1fr 1fr; }
  .providers::before, .providers::after { display: none; }
  .provider:last-child { grid-column: 1 / -1; }
}
@media (max-width: 620px) {
  .principles, .beachhead { grid-template-columns: 1fr; }
  .milestones { grid-template-columns: 1fr 1fr; row-gap: 2.2rem; }
  .milestones::before, .milestone-progress { display: none; }
  .credit-math { margin-left: 0; }
  .sky-hero { padding-bottom: 7rem; }
}