/* Hallmark · genre: atmospheric (studied-DNA deviation: light bands + glass + cool accent)
 * macrostructure: Split Studio · hero: H2 split-diptych (ratio 7/5, right=glass render, divider=negative space)
 * nav: N10 floating-on-scroll-morph · footer: Ft1 mast-headed
 * theme: studied-DNA (source: nivorix_hp_material/nivorix_hp_image.png — user's own comp)
 * enrichment: Tier C supplied stills + Tier B hand-built SVG ribbon
 * paper: oklch(97.31% 0.0041 91.45) snow / oklch(20.66% 0.0101 248.31) sumi · accent: oklch(34.28% 0.0705 252.44) indigo
 */

/* ============================================================
   RESET
   ============================================================ */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

html, body {
  overflow-x: clip;
}

body {
  background: var(--color-snow);
  color: var(--color-n700);
  font-family: var(--font-body);
  font-weight: var(--fw-regular);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
  position: relative;
}

img { display: block; max-width: 100%; height: auto; }
ul, ol { list-style: none; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }
table { border-collapse: collapse; width: 100%; }
svg { display: block; }

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: var(--fw-semibold);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  word-break: keep-all;
  overflow-wrap: anywhere;
  min-width: 0;
}

main { position: relative; z-index: 1; }

/* ============================================================
   LAYOUT PRIMITIVES
   ============================================================ */
.section {
  position: relative;
  z-index: 1;
  padding-block: var(--space-4xl);
}

.section--snow { background: var(--color-snow); color: var(--color-n700); }
.section--sumi { background: var(--color-sumi); color: var(--color-snow); }

.section__inner {
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--space-lg);
}

.section__heading {
  font-size: var(--fs-2xl);
  margin-top: var(--space-sm);
  max-width: 26ch;
}
.section__heading--light { color: var(--color-snow); }

.section__lead {
  margin-top: var(--space-md);
  max-width: 56ch;
  color: var(--color-n500);
  font-size: var(--fs-base);
}
.section__lead--light { color: var(--color-silver); }

.eyebrow {
  display: block;
  font-family: var(--font-display);
  font-size: var(--fs-2xs);
  font-weight: var(--fw-medium);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-indigo);
}
.eyebrow--light { color: var(--color-light-gold); }

/* ============================================================
   BUTTONS — 8 states: default / hover / focus-visible / active /
   disabled / loading / error / success
   ============================================================ */
.btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2xs);
  white-space: nowrap;
  padding: var(--space-sm) var(--space-lg);
  border-radius: var(--radius-pill);
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  letter-spacing: 0.02em;
  min-height: 44px;
  transition: background-color var(--dur-base) var(--ease-out),
              color var(--dur-base) var(--ease-out),
              opacity var(--dur-base) var(--ease-out),
              transform var(--dur-fast) var(--ease-out);
}
.btn:active { transform: scale(0.97); }

.btn__arrow { display: inline-block; transition: transform var(--dur-base) var(--ease-out); }
.btn:hover .btn__arrow { transform: translateX(3px); }

.btn--indigo {
  background: var(--color-indigo);
  color: var(--color-snow);
}
.btn--indigo:hover { background: var(--color-n600); }
.btn--indigo:focus-visible {
  outline: 2px solid var(--color-light-cyan);
  outline-offset: 2px;
  transition: none;
}

.btn--ghost {
  background: transparent;
  color: var(--color-n700);
  border: var(--rule-hairline);
}
.btn--ghost:hover { background: var(--color-paper-2); }
.btn--ghost:focus-visible {
  outline: 2px solid var(--color-indigo);
  outline-offset: 2px;
  transition: none;
}

.btn--ghost-dark {
  color: var(--color-snow);
  border-color: var(--color-n500);
}
.btn--ghost-dark:hover { background: var(--color-paper-3); }
.btn--ghost-dark:focus-visible { outline-color: var(--color-light-cyan); }

.btn--sm { padding: var(--space-xs) var(--space-md); font-size: var(--fs-xs); }

.btn[disabled],
.btn.is-disabled {
  opacity: 0.4;
  pointer-events: none;
  cursor: not-allowed;
}

.btn.is-loading {
  color: transparent;
  pointer-events: none;
}
.btn.is-loading::after {
  content: "";
  position: absolute;
  inset: 0;
  margin: auto;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: 2px solid currentColor;
  border-top-color: transparent;
  color: var(--color-snow);
  animation: btn-spin 700ms linear infinite;
}
@keyframes btn-spin { to { transform: rotate(360deg); } }

.btn.is-error {
  background: var(--color-n700);
  color: var(--color-light-spark);
  border: 1px solid var(--color-light-spark);
}

.btn.is-success {
  background: var(--color-n700);
  color: var(--color-light-cyan);
  border: 1px solid var(--color-light-cyan);
}

/* generic focus-visible fallback for any interactive element without a specific rule */
a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--color-indigo);
  outline-offset: 2px;
  transition: none;
}

/* ============================================================
   RIBBON — full-page SVG, single continuous path
   ============================================================ */
.ribbon-layer {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 100%;
  height: auto;
  z-index: 0;
  pointer-events: none;
  overflow: clip;
}
.ribbon-svg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}
.ribbon-path {
  opacity: 0.5;
}

@media (prefers-reduced-motion: reduce) {
  .ribbon-path { stroke-dashoffset: 0 !important; }
}

/* ============================================================
   HEADER — N10 floating-on-scroll-morph
   ============================================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  padding-block: var(--space-md);
  background-color: transparent;
  transition: background-color var(--dur-base) var(--ease-out),
              box-shadow var(--dur-base) var(--ease-out),
              padding-block var(--dur-base) var(--ease-out);
}

.site-header.is-scrolled {
  background-color: color-mix(in oklch, var(--color-snow) 92%, transparent);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--color-n300);
  padding-block: var(--space-xs);
}

.site-header__inner {
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--space-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
}

.site-header__logo-img {
  height: 32px;
  width: auto;
  transition: transform var(--dur-base) var(--ease-out);
}

.site-header__nav { flex: 1; display: flex; justify-content: center; }

.site-header__menu {
  display: flex;
  gap: var(--space-lg);
  font-size: var(--fs-xs);
  font-weight: var(--fw-medium);
  letter-spacing: 0.08em;
}
.site-header__menu a {
  position: relative;
  padding-block: var(--space-3xs);
  white-space: nowrap;
}
.site-header__menu a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: 0;
  height: 1px;
  background: var(--color-indigo);
  transition: right var(--dur-base) var(--ease-out);
}
.site-header__menu a:hover::after,
.site-header__menu a:focus-visible::after { right: 0; }

.site-header__nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  align-items: center;
  justify-content: center;
}
.site-header__nav-toggle span {
  width: 20px;
  height: 1.5px;
  background: var(--color-n700);
  transition: transform var(--dur-base) var(--ease-out), opacity var(--dur-base) var(--ease-out);
}

.site-header__cta { flex-shrink: 0; }

.site-header__social { display: none; }

.social-rail {
  position: fixed;
  z-index: 10;
  top: 50%;
  right: clamp(0.75rem, 2vw, 2rem);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  transform: translateY(-50%);
}
.social-link {
  display: inline-grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border: 1px solid color-mix(in srgb, var(--color-n600) 84%, transparent);
  border-radius: 50%;
  background: color-mix(in srgb, var(--color-sumi) 88%, transparent);
  box-shadow: 0 8px 20px color-mix(in srgb, var(--color-sumi) 18%, transparent);
  transition: border-color var(--transition-fast), background-color var(--transition-fast), transform var(--transition-fast);
}
.social-link:hover {
  border-color: var(--color-light-cyan);
  background: color-mix(in srgb, var(--color-light-cyan) 14%, var(--color-sumi));
  transform: translateY(-2px);
}
.social-link img {
  width: 18px;
  height: 18px;
  object-fit: contain;
}

/* ============================================================
   HERO — H2 split-diptych (7/5)
   ============================================================ */
.hero {
  position: relative;
  z-index: 1;
  padding-top: calc(var(--space-4xl) + var(--space-2xl));
  padding-bottom: var(--space-4xl);
  background-color: var(--color-snow);
  background-image: url("../assets/img/hero-glass-object.webp");
  background-repeat: no-repeat;
  background-position: right 9% center;
  background-size: min(54vw, 700px);
}

.hero__grid {
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--space-lg);
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: var(--space-2xl);
  align-items: center;
}

.hero__copy > * + * { margin-top: var(--space-md); }

.hero__heading {
  font-size: var(--fs-4xl);
  max-width: 14ch;
}

.hero__lead {
  font-size: var(--fs-md);
  color: var(--color-n600);
  max-width: 34ch;
}

.hero__sub {
  font-size: var(--fs-sm);
  color: var(--color-n500);
  max-width: 40ch;
}

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.hero__note {
  font-size: var(--fs-xs);
  color: var(--color-n400);
}

.hero__media {
  position: relative;
  aspect-ratio: 1 / 1;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-paper-2);
}
.hero__media-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ============================================================
   REFERENCE COMPOSITION — translucent cards, luminous separators
   The supplied composition uses a quiet paper field interrupted by
   dark chapters. These refinements keep the source content intact,
   while making that rhythm visible in the built page.
   ============================================================ */
.section--snow::after,
.section--sumi::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}
.section--snow::after {
  background:
    radial-gradient(ellipse 56% 22% at 100% 100%, color-mix(in srgb, var(--color-light-cyan) 20%, transparent), transparent 70%),
    radial-gradient(ellipse 45% 18% at 0% 0%, color-mix(in srgb, var(--color-light-gold) 18%, transparent), transparent 72%);
}
.section--sumi::after {
  background:
    radial-gradient(ellipse 46% 28% at 96% 30%, color-mix(in srgb, var(--color-light-cyan) 15%, transparent), transparent 72%),
    radial-gradient(ellipse 42% 24% at 6% 96%, color-mix(in srgb, var(--color-light-gold) 12%, transparent), transparent 74%);
}

.section--sumi .section__inner,
.section--snow .section__inner { position: relative; z-index: 1; }

.pill,
.tilt-card__link,
.entry-card,
.etymology__card {
  border-radius: 7px;
  box-shadow: 0 10px 28px color-mix(in srgb, var(--color-sumi) 7%, transparent), inset 0 1px 0 color-mix(in srgb, white 65%, transparent);
}
.section--sumi .approach__card,
.section--sumi .entry-card,
.section--sumi .why__card {
  border-color: color-mix(in srgb, var(--color-light-cyan) 32%, var(--color-n600));
}

/* HERO — adapted from 20260805_hero-glass-ribbon.html */
.hero {
  min-height: max(680px, 100svh);
  padding: 0;
  overflow: hidden;
  isolation: isolate;
  display: grid;
  align-items: stretch;
  background: var(--color-snow);
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(circle at 62% 31%, color-mix(in srgb, var(--color-light-gold) 22%, transparent), transparent 27%),
    radial-gradient(circle at 91% 66%, color-mix(in srgb, var(--color-light-cyan) 18%, transparent), transparent 31%);
}
.hero__canvas {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  z-index: -1;
  -webkit-mask-image: linear-gradient(to right, transparent 0%, rgba(0,0,0,.22) 28%, #000 47%);
  mask-image: linear-gradient(to right, transparent 0%, rgba(0,0,0,.22) 28%, #000 47%);
}
.hero__inner {
  width: min(100%, calc(var(--content-max) + 8rem));
  min-height: inherit;
  margin-inline: auto;
  padding: clamp(8rem, 15vh, 12rem) clamp(2rem, 6vw, 5rem) clamp(4rem, 10vh, 8rem);
  display: flex;
  align-items: center;
  pointer-events: none;
}
.hero__copy { max-width: 42rem; pointer-events: auto; }
.hero__copy > * + * { margin-top: var(--space-md); }
.hero__label { color: var(--color-n500); }
.hero__heading {
  font-size: clamp(2.6rem, 5.2vw, 4.5rem);
  letter-spacing: .045em;
  line-height: 1.33;
  max-width: 14ch;
}
.hero__line { display: block; white-space: nowrap; }
.hero__sp-break { display: none; }
.hero__lead { max-width: 32em; font-size: var(--fs-md); color: var(--color-n600); line-height: 2; }
.hero__cta { display: flex; flex-wrap: wrap; gap: var(--space-sm); margin-top: var(--space-xl) !important; }
.hero__cta .btn { border-radius: 3px; padding-inline: 1.5rem; }
.hero__cta .btn--indigo { background: var(--color-sumi); box-shadow: 0 9px 20px color-mix(in srgb, var(--color-sumi) 20%, transparent); }
.hero__cta .btn--ghost { background: color-mix(in srgb, var(--color-snow) 56%, transparent); backdrop-filter: blur(8px); }
.hero__web-cta { margin-top: var(--space-sm) !important; }
.hero__web-cta .btn { border-radius: 3px; padding-inline: 1.5rem; background: color-mix(in srgb, var(--color-snow) 56%, transparent); backdrop-filter: blur(8px); }
.hero__note { margin-top: var(--space-lg) !important; letter-spacing: .06em; }

@media (max-width: 900px) {
  .hero { min-height: 760px; }
  .hero__canvas {
    opacity: .88;
    -webkit-mask-image: linear-gradient(to bottom, transparent 0%, rgba(0,0,0,.20) 28%, #000 48%);
    mask-image: linear-gradient(to bottom, transparent 0%, rgba(0,0,0,.20) 28%, #000 48%);
  }
  .hero__inner { align-items: flex-start; padding-top: 9.5rem; }
  .hero__heading { font-size: clamp(2.45rem, 10vw, 4rem); }
  .hero__sp-break { display: inline; }
  .hero { background-position: 82% 78%; background-size: min(92vw, 520px); }
}

@media (max-width: 640px) {
  .hero { min-height: 690px; }
  .hero__inner { padding: 8rem var(--space-lg) 3rem; }
  .hero__lead { font-size: var(--fs-base); line-height: 1.9; }
  .hero__cta { margin-top: var(--space-lg) !important; }
  .hero { background-position: 75% 90%; background-size: 480px; }
}

/* ============================================================
   REVEAL — IntersectionObserver driven
   no-js pattern: initial hidden state only applies once js runs
   (document.documentElement gets .js via inline head script).
   With JS disabled/failed, .reveal stays in its unstyled (visible)
   state so content is never hidden.
   ============================================================ */
.js .reveal {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity var(--dur-reveal) var(--ease-out),
              transform var(--dur-reveal) var(--ease-out);
}
.js .reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .js .reveal {
    transform: none;
    transition: opacity 150ms linear;
  }
}

@media print {
  .reveal { opacity: 1 !important; transform: none !important; }
}

/* ============================================================
   ABOUT
   ============================================================ */
.about__body { max-width: 60ch; color: var(--color-silver); }
.about__body p + p { margin-top: var(--space-sm); }

.about__promise {
  margin-top: var(--space-lg);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-2xs) var(--space-lg);
  max-width: 60ch;
}
.about__promise li {
  position: relative;
  padding-left: var(--space-md);
  color: var(--color-silver);
  font-size: var(--fs-sm);
}
.about__promise li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 1px;
  background: var(--color-light-gold);
}

.etymology {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-md);
}
.etymology__card {
  border: 1px solid var(--color-n600);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  background: var(--color-paper-3);
}
.etymology__label {
  font-family: var(--font-display);
  font-size: var(--fs-lg);
  font-weight: var(--fw-semibold);
  color: var(--color-light-cyan);
  letter-spacing: var(--tracking-logo);
}
.etymology__origin {
  margin-top: var(--space-2xs);
  font-size: var(--fs-2xs);
  color: var(--color-n400);
}
.etymology__meaning {
  margin-top: var(--space-2xs);
  font-size: var(--fs-xs);
  color: var(--color-silver);
}

.about__predecessor {
  margin-top: var(--space-2xl);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  color: var(--color-n400);
  font-size: var(--fs-xs);
  max-width: 56ch;
}
.about__predecessor-logo {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  opacity: 0.85;
}
.about__predecessor strong { color: var(--color-silver); font-weight: var(--fw-medium); }

/* ============================================================
   PROBLEMS — glass pills
   ============================================================ */
.pills {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-sm);
}
.pill {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  padding: var(--space-md);
  border-radius: var(--radius-lg);
  background: color-mix(in oklch, var(--color-paper-2) 70%, transparent);
  border: 1px solid var(--color-n300);
  font-size: var(--fs-xs);
  color: var(--color-n600);
}
.pill__icon {
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  color: var(--color-indigo);
}

/* ============================================================
   APPROACH
   ============================================================ */
.approach__grid {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-md);
}
.approach__card {
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  background: var(--color-paper-3);
  border: 1px solid var(--color-n600);
}
.approach__icon,
.flow__icon {
  display: block;
  width: 62px;
  height: 62px;
  margin-bottom: var(--space-md);
  padding: 4px;
  border: 1px solid color-mix(in srgb, var(--color-light-cyan) 34%, var(--color-n600));
  border-radius: 10px;
  background: color-mix(in srgb, var(--color-paper-3) 88%, var(--color-sumi));
  box-shadow: 0 6px 16px color-mix(in srgb, var(--color-sumi) 24%, transparent);
  opacity: 1;
}
.approach__num {
  font-family: var(--font-display);
  font-size: var(--fs-3xl);
  color: var(--color-light-cyan);
  font-weight: var(--fw-semibold);
}
.approach__title {
  margin-top: var(--space-2xs);
  font-size: var(--fs-md);
  color: var(--color-snow);
}
.approach__desc {
  margin-top: var(--space-2xs);
  font-size: var(--fs-xs);
  color: var(--color-silver);
}

/* ============================================================
   TILT CARD — 3D tilt + glare (ported from n1-inc.co.jp reference)
   ============================================================ */
.tilt-card {
  perspective: 100rem;
  overflow: visible;
}
.tilt-card__link {
  --tilt-rotate-x: 0deg;
  --tilt-rotate-y: 0deg;
  --tilt-mouse-x: 50%;
  --tilt-mouse-y: 50%;

  display: block;
  position: relative;
  height: 100%;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-paper-2);
  border: 1px solid var(--color-n300);
  padding: var(--space-lg);

  transform: rotateX(var(--tilt-rotate-x)) rotateY(var(--tilt-rotate-y)) translateZ(0);
  transform-style: preserve-3d;
  transform-origin: center;

  transition: transform var(--dur-slow) var(--ease-out);
  will-change: transform;
}
.tilt-card__link.is-tilting { transition: transform 120ms linear; }

.tilt-card--dark .tilt-card__link {
  background: var(--color-sumi);
  border-color: var(--color-n600);
}

.tilt-card__glare {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 3;
  background: radial-gradient(
    circle at var(--tilt-mouse-x) var(--tilt-mouse-y),
    color-mix(in oklch, var(--color-glare) 16%, transparent),
    color-mix(in oklch, var(--color-glare) 0%, transparent) 42%
  );
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur-base) var(--ease-out);
}
.tilt-card__link.is-tilting .tilt-card__glare { opacity: 1; }

@media (hover: none), (pointer: coarse) {
  .tilt-card { perspective: none; }
  .tilt-card__link { transform: none; }
  .tilt-card__glare { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  .tilt-card__link { transform: none; transition: none; }
  .tilt-card__glare { display: none; }
}

/* ============================================================
   SERVICES
   ============================================================ */
.services__grid {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-md);
  align-items: stretch;
}
.tilt-card__icon {
  display: block;
  width: 64px;
  height: 64px;
  margin: -2px 0 var(--space-md);
  padding: 4px;
  border: 1px solid color-mix(in srgb, var(--color-n300) 70%, transparent);
  border-radius: 10px;
  background: var(--color-paper-2);
  box-shadow: 0 6px 16px color-mix(in srgb, var(--color-sumi) 10%, transparent);
}
.tilt-card--dark .tilt-card__icon {
  border-color: color-mix(in srgb, var(--color-light-cyan) 35%, var(--color-n600));
  background: color-mix(in srgb, var(--color-paper-3) 82%, var(--color-sumi));
}
.tilt-card__title { font-size: var(--fs-md); color: var(--color-n700); }
.tilt-card--dark .tilt-card__title { color: var(--color-snow); }

.tilt-card__list { margin-top: var(--space-sm); }
.tilt-card__list li {
  font-size: var(--fs-xs);
  color: var(--color-n500);
  line-height: var(--leading-body);
}
.tilt-card__list li + li { margin-top: var(--space-2xs); }
.tilt-card--dark .tilt-card__list li { color: var(--color-silver); }

.tilt-card__more {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3xs);
  margin-top: var(--space-md);
  font-size: var(--fs-2xs);
  font-weight: var(--fw-medium);
  color: var(--color-indigo);
}
.tilt-card--dark .tilt-card__more { color: var(--color-light-cyan); }

/* ============================================================
   WORKS — split into Snow (marquee) / Deep Sumi (grid) bands
   ============================================================ */
.section--works__top { padding-bottom: var(--space-2xl); }
.section--works__bottom { padding-top: var(--space-2xl); }

.marquee {
  margin-top: var(--space-2xl);
  overflow: clip;
  -webkit-mask-image: linear-gradient(90deg, transparent, black 8%, black 92%, transparent);
  mask-image: linear-gradient(90deg, transparent, black 8%, black 92%, transparent);
}
.marquee__track {
  display: flex;
  width: max-content;
  animation: marquee-scroll 36s linear infinite;
}
.marquee__list {
  display: flex;
  gap: var(--space-lg);
  padding-inline-end: var(--space-lg);
}
.marquee__list img {
  width: 96px;
  height: 96px;
  object-fit: contain;
  mix-blend-mode: multiply;
  filter: grayscale(1);
  opacity: 0.85;
  transition: filter var(--dur-base) var(--ease-out), opacity var(--dur-base) var(--ease-out);
}
.marquee__list img:hover {
  filter: grayscale(0);
  opacity: 1;
}

@keyframes marquee-scroll {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

@media (prefers-reduced-motion: reduce) {
  .marquee { mask-image: none; -webkit-mask-image: none; }
  .marquee__track { animation: none; width: 100%; flex-wrap: wrap; }
  .marquee__list { flex-wrap: wrap; }
  .marquee__list[aria-hidden="true"] { display: none; }
  .marquee__list img { filter: grayscale(0); opacity: 1; }
}

.works__grid {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-md);
}
.tilt-card--work .tilt-card__link { padding: 0; background: var(--color-paper-3); }
.tilt-card--work .tilt-card__link img { width: 100%; height: 100%; object-fit: cover; aspect-ratio: 1 / 1; }
.works__cta { margin-top: clamp(4.5rem, 6vw, 6rem); }

/* ============================================================
   AI TRAINING
   ============================================================ */
.entry-grid {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-sm);
}
.entry-card {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-lg);
  border-radius: var(--radius-pill);
  border: 1px solid var(--color-n600);
  background: var(--color-paper-3);
  color: var(--color-snow);
  font-size: var(--fs-sm);
  min-height: 44px;
  transition: background-color var(--dur-base) var(--ease-out), border-color var(--dur-base) var(--ease-out);
}
.entry-card:hover { background: var(--color-n600); border-color: var(--color-n500); }
.entry-card:focus-visible { outline: 2px solid var(--color-light-cyan); outline-offset: 2px; transition: none; }
.entry-card:active { background: var(--color-sumi); }
.entry-card__icon { width: 22px; height: 22px; flex-shrink: 0; color: var(--color-light-gold); }
.entry-card__arrow { margin-left: auto; color: var(--color-n400); }

.ai-training__cta { margin-top: var(--space-2xl); }

/* ============================================================
   FLOW
   ============================================================ */
.flow__list {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-md);
}
.flow__step { position: relative; }
.flow__num {
  font-family: var(--font-display);
  font-size: var(--fs-xl);
  color: var(--color-indigo);
  font-weight: var(--fw-semibold);
}
.flow__title { margin-top: var(--space-2xs); font-size: var(--fs-md); }
.flow__desc { margin-top: var(--space-2xs); font-size: var(--fs-xs); color: var(--color-n500); }

/* ============================================================
   WHY NIVORIX
   ============================================================ */
.why__grid {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-lg) var(--space-2xl);
}
.why__card { border-top: var(--rule-hairline-dark); padding-top: var(--space-md); }
.why__num { font-family: var(--font-display); font-size: var(--fs-sm); color: var(--color-light-gold); }
.why__title { margin-top: var(--space-2xs); font-size: var(--fs-md); color: var(--color-snow); }
.why__desc { margin-top: var(--space-2xs); font-size: var(--fs-xs); color: var(--color-silver); }

/* ============================================================
   支援の型 (support table)
   ============================================================ */
.table-wrap {
  margin-top: var(--space-2xl);
  overflow-x: auto;
}
.support-table {
  font-size: var(--fs-xs);
}
.support-table th,
.support-table td {
  text-align: left;
  padding: var(--space-sm);
  border-bottom: var(--rule-hairline);
  vertical-align: top;
}
.support-table th {
  font-weight: var(--fw-medium);
  color: var(--color-n500);
  font-size: var(--fs-2xs);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.support-table__note {
  margin-top: var(--space-md);
  font-size: var(--fs-2xs);
  color: var(--color-n400);
}

/* ============================================================
   PROFILE (Nivorixについて)
   ============================================================ */
.profile-table {
  margin-top: var(--space-2xl);
  max-width: 640px;
}
.profile-table__row {
  display: grid;
  grid-template-columns: minmax(0, 6rem) minmax(0, 1fr);
  gap: var(--space-md);
  padding-block: var(--space-sm);
  border-bottom: 1px solid var(--color-n600);
  font-size: var(--fs-sm);
}
.profile-table__row dt { color: var(--color-n400); }
.profile-table__row dd { color: var(--color-snow); }

/* ============================================================
   FAQ — native details/summary
   ============================================================ */
.faq-list {
  margin-top: var(--space-2xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-2xs);
}
.faq-item {
  border-bottom: var(--rule-hairline);
  padding-block: var(--space-sm);
}
.faq-item summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  padding-block: var(--space-xs);
  min-height: 44px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  flex-shrink: 0;
  font-size: var(--fs-lg);
  font-weight: var(--fw-regular);
  color: var(--color-indigo);
  transition: transform var(--dur-base) var(--ease-out);
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p {
  margin-top: var(--space-sm);
  padding-right: var(--space-2xl);
  font-size: var(--fs-sm);
  color: var(--color-n500);
}

@media (prefers-reduced-motion: reduce) {
  .faq-item summary::after { transition: none; }
}

/* ============================================================
   FINAL CTA
   ============================================================ */
.final-cta { position: relative; overflow: hidden; text-align: center; }
.final-cta__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
}
.final-cta__accent {
  position: absolute;
  top: -60px;
  right: -60px;
  width: 260px;
  height: 260px;
  opacity: 0.22;
  z-index: -1;
  -webkit-mask-image: radial-gradient(circle at 65% 35%, black, transparent 68%);
  mask-image: radial-gradient(circle at 65% 35%, black, transparent 68%);
}
.final-cta .section__heading { max-width: 20ch; }
.final-cta .section__lead { max-width: 44ch; }
.final-cta__buttons {
  margin-top: var(--space-xl);
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-sm);
}

/* ============================================================
   FOOTER — Ft1 mast-headed
   ============================================================ */
.site-footer {
  position: relative;
  z-index: 1;
  background: var(--color-sumi);
  color: var(--color-silver);
  padding-block: var(--space-2xl) var(--space-xl);
  border-top: 1px solid var(--color-n600);
}
.site-footer__inner {
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}
.site-footer__mast {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}
.site-footer__symbol { width: auto; height: 28px; }
.site-footer__wordmark { height: 28px; width: auto; }

.site-footer__nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md) var(--space-lg);
  font-size: var(--fs-xs);
  letter-spacing: 0.04em;
}
.site-footer__nav a:hover { color: var(--color-snow); }

.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  font-size: var(--fs-2xs);
  color: var(--color-n400);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-n600);
}
.site-footer__legal a:hover { color: var(--color-silver); }

.site-footer__copy {
  font-size: var(--fs-2xs);
  color: var(--color-n500);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1024px) {
  .services__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .works__grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .why__grid { grid-template-columns: minmax(0, 1fr); }
  .etymology { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 900px) {
  .site-header__nav { display: none; }
  .site-header__nav-toggle { display: flex; margin-left: auto; }
  .social-rail { display: none; }

  .site-header__nav.is-open {
    display: flex;
    flex-direction: column;
    position: fixed;
    inset: 64px var(--space-lg) auto;
    background: var(--color-snow);
    border: var(--rule-hairline);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    box-shadow: 0 12px 32px color-mix(in oklch, var(--shadow-color) 12%, transparent);
  }
  .site-header__nav.is-open .site-header__menu {
    flex-direction: column;
    gap: var(--space-md);
  }
  .site-header__nav.is-open .site-header__social {
    display: flex;
    gap: var(--space-sm);
    padding-top: var(--space-md);
    border-top: var(--rule-hairline);
  }
  .site-header__nav.is-open ~ .site-header__cta { visibility: hidden; }
  .site-header__social .social-link {
    width: 44px;
    height: 44px;
    background: var(--color-sumi);
  }

  .hero__grid { grid-template-columns: minmax(0, 1fr); }
  .hero__media { order: -1; max-width: 420px; margin-inline: auto; width: 100%; }
  .hero__heading { max-width: none; }

  .approach__grid { grid-template-columns: minmax(0, 1fr); }
  .pills { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .flow__list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .entry-grid { grid-template-columns: minmax(0, 1fr); }
  .about__promise { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 768px) {
  .works__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .services__grid { grid-template-columns: minmax(0, 1fr); }

  .profile-table__row { grid-template-columns: minmax(0, 1fr); gap: var(--space-2xs); }
}

@media (max-width: 640px) {
  :root { --fs-4xl: 2.5rem; --fs-3xl: 2.25rem; --fs-2xl: 1.75rem; }

  .section { padding-block: var(--space-3xl); }
  .hero { padding: 0; }

  .pills { grid-template-columns: minmax(0, 1fr); }
  .flow__list { grid-template-columns: minmax(0, 1fr); }

  .hero__cta { flex-direction: column; align-items: stretch; }
  .hero__cta .btn { width: 100%; }
  .hero__web-cta .btn { width: 100%; }

  .final-cta__buttons { flex-direction: column; align-items: stretch; width: 100%; }
  .final-cta__buttons .btn { width: 100%; }
}

@media (max-width: 414px) {
  .works__grid { grid-template-columns: minmax(0, 1fr); }
  .site-header__logo-img { height: 20px; }
  .section__inner { padding-inline: var(--space-md); }
  .hero__grid { padding-inline: var(--space-md); }

  .btn { min-height: 44px; min-width: 44px; }
  .entry-card { min-height: 44px; }
  .faq-item summary { min-height: 44px; }
  .site-header__nav-toggle { width: 44px; height: 44px; }

  /* long CTA copy must stay on one line without overflowing the viewport */
  .btn {
    padding-inline: var(--space-md);
    font-size: var(--fs-xs);
    gap: var(--space-3xs);
  }
  .entry-card { padding-inline: var(--space-md); font-size: var(--fs-xs); }

  /* tap targets ≥ 44×44px */
  .site-header__logo {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 44px;
    min-height: 44px;
  }
  .site-footer__nav a,
  .site-footer__legal a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 44px;
    min-width: 44px;
  }
}

/* ============================================================
   HERO RESPONSIVE REFINEMENT
   Keep the full-screen glass composition on desktop, but avoid the
   compounded outer/inner padding that made the mobile hero feel stretched.
   ============================================================ */
@media (max-width: 640px) {
  .hero {
    min-height: 0;
    background-position: 70% 100%;
    background-size: 440px;
  }
  .hero__inner {
    min-height: 0;
    padding: 6.75rem var(--space-md) 2.5rem;
  }
  .hero__heading {
    max-width: 10ch;
    font-size: clamp(2.1rem, 9.6vw, 2.45rem);
    line-height: 1.34;
  }
  .hero__lead {
    font-size: .98rem;
    line-height: 1.82;
  }
  .hero__copy > * + * { margin-top: 1rem; }
  .hero__cta {
    gap: .65rem;
    margin-top: 1.35rem !important;
  }
  .hero__cta .btn {
    min-height: 54px;
    padding-block: .8rem;
  }
  .hero__note { margin-top: 1.15rem !important; }
  .tilt-card__icon { width: 58px; height: 58px; margin-bottom: 1.15rem; }
}