@charset "utf-8";

/* =========================================================
   Design tokens
   ========================================================= */
:root {
  --c-bg: #0a0a0a;
  --c-bg-elev: #141414;
  --c-bg-elev2: #1d1d1d;
  --c-fg: #f2f2f2;
  --c-fg-muted: #a8a8a8;
  --c-border: #2a2a2a;
  --c-accent: #c50018;          /* 背景・ボーダー・装飾用 */
  --c-accent-text: #ff2a2a;     /* 暗背景上の文字色用 (WCAG AA 適合) */
  --c-accent-ink: #ffffff;

  --ff-sans: "Noto Sans JP", "Noto Sans", system-ui, -apple-system, "Segoe UI", sans-serif;

  --fs-base: clamp(1.125rem, 1.05rem + 0.35vw, 1.25rem);
  --fs-sm: clamp(1rem, 0.95rem + 0.15vw, 1.0625rem);
  --fs-lead: clamp(1.25rem, 1.1rem + 0.6vw, 1.5rem);
  --fs-h2: clamp(2.125rem, 1.5rem + 2.5vw, 3.625rem);
  --fs-h3: clamp(1.375rem, 1.1rem + 1.1vw, 1.875rem);
  --fs-display: clamp(2.75rem, 1.7rem + 4.5vw, 5.5rem);
  --fs-eyebrow: clamp(0.8125rem, 0.75rem + 0.25vw, 0.9375rem);

  --lh-body: 1.85;
  --lh-tight: 1.3;

  --s-1: 0.5rem;
  --s-2: 1rem;
  --s-3: 1.5rem;
  --s-4: 2rem;
  --s-5: 3rem;
  --s-6: 5rem;
  --s-7: 8rem;

  --container: min(1200px, 100% - 2rem);
  --container-wide: min(1440px, 100% - 2rem);

  --header-h: 72px;

  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);
}

/* =========================================================
   Reset (modern, minimal)
   ========================================================= */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: var(--header-h); }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}
body {
  margin: 0;
  background: var(--c-bg);
  color: var(--c-fg);
  font-family: var(--ff-sans);
  font-size: var(--fs-base);
  line-height: var(--lh-body);
  font-feature-settings: "palt";
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, picture, svg, video { display: block; max-width: 100%; height: auto; }
h1, h2, h3, h4, p, ul, ol, blockquote, figure { margin: 0; }
ul, ol { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
a:focus-visible, button:focus-visible {
  outline: 2px solid var(--c-accent);
  outline-offset: 3px;
}
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; padding: 0; }
::selection { background: var(--c-accent); color: var(--c-accent-ink); }

/* =========================================================
   Utilities
   ========================================================= */
.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0);
  white-space: nowrap; border: 0;
}
/* =========================================================
   Header
   ========================================================= */
.site-header {
  position: fixed;
  inset-block-start: 0;
  inset-inline: 0;
  z-index: 100;
  height: var(--header-h);
  background: color-mix(in srgb, var(--c-bg) 80%, transparent);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-block-end: 1px solid transparent;
  transition: background 200ms var(--ease), border-color 200ms var(--ease);
}
.site-header[data-scrolled="true"] {
  background: color-mix(in srgb, var(--c-bg) 92%, transparent);
  border-block-end-color: var(--c-border);
}
.site-header__inner {
  max-width: var(--container-wide);
  height: 100%;
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.site-header__brand img {
  height: 44px;
  width: auto;
}

/* =========================================================
   Nav
   ========================================================= */
.site-nav__list {
  display: flex;
  gap: clamp(1rem, 0.5rem + 1.5vw, 2rem);
  align-items: center;
  font-size: var(--fs-sm);
  letter-spacing: 0.02em;
}
.site-nav__list a {
  position: relative;
  padding-block: 0.5rem;
  color: var(--c-fg);
  transition: color 150ms var(--ease);
}
.site-nav__list a::after {
  content: "";
  position: absolute;
  inset-block-end: 0;
  inset-inline: 0;
  height: 2px;
  background: var(--c-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 200ms var(--ease);
}
.site-nav__list a:hover::after,
.site-nav__list a:focus-visible::after {
  transform: scaleX(1);
}

.site-nav__toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  flex-direction: column;
  justify-content: space-between;
  align-items: stretch;
}
.site-nav__toggle-bar {
  display: block;
  height: 2px;
  background: var(--c-fg);
  transition: transform 200ms var(--ease), opacity 200ms var(--ease);
  transform-origin: center;
}
.site-nav__toggle[aria-expanded="true"] .site-nav__toggle-bar:nth-child(2) { transform: translateY(8px) rotate(45deg); }
.site-nav__toggle[aria-expanded="true"] .site-nav__toggle-bar:nth-child(3) { opacity: 0; }
.site-nav__toggle[aria-expanded="true"] .site-nav__toggle-bar:nth-child(4) { transform: translateY(-8px) rotate(-45deg); }

@media (max-width: 720px) {
  .site-nav__toggle { display: flex; }
  .site-nav__list {
    position: fixed;
    inset-block-start: var(--header-h);
    inset-inline: 0;
    flex-direction: column;
    gap: 0;
    background: var(--c-bg);
    border-block-start: 1px solid var(--c-border);
    padding: 0.5rem 1rem 1.5rem;
    transform: translateY(-110%);
    transition: transform 250ms var(--ease);
    visibility: hidden;
  }
  .site-nav__list a {
    display: block;
    padding-block: 0.875rem;
    border-block-end: 1px solid var(--c-border);
    font-size: 1rem;
  }
  .site-nav[data-open="true"] .site-nav__list {
    transform: translateY(0);
    visibility: visible;
  }
}

/* =========================================================
   Section base
   ========================================================= */
.section {
  position: relative;
  padding-block: clamp(4rem, 3rem + 4vw, 8rem);
  overflow: clip;
  container-type: inline-size;
}
.section + .section {
  border-block-start: 1px solid var(--c-border);
}
.section__inner {
  position: relative;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: clamp(1rem, 4vw, 2rem);
  z-index: 2;
}
.section__inner--center { text-align: center; }
.section__inner--grid {
  display: grid;
  gap: clamp(2rem, 1rem + 4vw, 4rem);
  grid-template-columns: 1fr;
}
@container (min-width: 880px) {
  .section__inner--grid { grid-template-columns: 1fr 1fr; align-items: center; }
}

.section__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.section__bg picture, .section__bg img {
  width: 100%; height: 100%;
}
.section__bg img { object-fit: cover; opacity: 0.55; }
.section__bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10,10,10,0.55), rgba(10,10,10,0.85));
  pointer-events: none;
}
.section__bg--right::after {
  background: linear-gradient(270deg, rgba(10,10,10,0.45) 0%, rgba(10,10,10,0.85) 60%, rgba(10,10,10,0.95) 100%);
}
.section__bg--left::after {
  background: linear-gradient(90deg, rgba(10,10,10,0.45) 0%, rgba(10,10,10,0.85) 60%, rgba(10,10,10,0.95) 100%);
}

.section__eyebrow {
  font-size: var(--fs-eyebrow);
  letter-spacing: 0.24em;
  font-weight: 700;
  color: var(--c-accent-text);
  text-transform: uppercase;
  margin-block-end: var(--s-2);
}
.section__title {
  font-size: var(--fs-h2);
  line-height: var(--lh-tight);
  font-weight: 700;
  letter-spacing: 0.02em;
  margin-block-end: var(--s-4);
}
.section__title em {
  font-style: normal;
  color: var(--c-accent-text);
  position: relative;
  padding-inline: 0.1em;
}

/* =========================================================
   Prose (long-form text inside sections)
   ========================================================= */
.prose > * + * { margin-block-start: 1.4em; }
.prose p { color: color-mix(in srgb, var(--c-fg) 92%, var(--c-fg-muted)); }
.prose__lead { font-size: var(--fs-lead); font-weight: 500; color: var(--c-fg) !important; }
.prose__quote {
  margin-block: 1.6em;
  padding: 1.25rem 1.5rem;
  border-inline-start: 3px solid var(--c-accent);
  background: var(--c-bg-elev);
  font-style: normal;
  color: var(--c-fg);
}
.prose ul, .prose ol { padding-inline-start: 1.5rem; }
.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }
.prose ul li, .prose ol li { margin-block: 0.4em; }
.prose table {
  width: 100%;
  border-collapse: collapse;
  margin-block: 1.5em;
}
.prose th, .prose td {
  padding: 0.6em 0.9em;
  border-block-end: 1px solid var(--c-border);
  text-align: start;
}
.prose th { background: var(--c-bg-elev); }

/* =========================================================
   Hero
   ========================================================= */
.section--hero {
  min-height: 100svh;
  display: flex;
  align-items: center;
  padding-block: var(--s-7);
}
.section--hero .section__bg img { opacity: 0.7; }
.section--hero .section__bg::after {
  background: linear-gradient(180deg, rgba(10,10,10,0.55) 0%, rgba(10,10,10,0.45) 35%, rgba(10,10,10,0.9) 100%);
}
.hero__eyebrow {
  font-size: var(--fs-eyebrow);
  letter-spacing: 0.32em;
  font-weight: 700;
  color: var(--c-fg);
  margin-block-end: var(--s-4);
}
.hero__title { margin-block-end: var(--s-4); display: flex; justify-content: center; }
.hero__logo {
  width: clamp(260px, 38vw, 540px);
  height: auto;
  filter: drop-shadow(0 4px 24px rgba(0,0,0,0.5));
}
.hero__copy {
  font-size: clamp(1.25rem, 1rem + 1.1vw, 1.875rem);
  font-weight: 500;
  letter-spacing: 0.05em;
  color: var(--c-fg);
}

/* =========================================================
   Origin
   ========================================================= */
.section--origin .section__bg img { opacity: 0.45; }

/* =========================================================
   Craftsmanship
   ========================================================= */
.section--craftsmanship .section__bg img { opacity: 0.4; }

@media (min-width: 880px) {
  .section--origin .section__inner {
    max-width: 760px;
    margin-inline-start: max(2rem, calc((100vw - 1200px) / 2));
    margin-inline-end: 0;
  }
  .section--craftsmanship .section__inner {
    max-width: 760px;
    margin-inline-end: max(2rem, calc((100vw - 1200px) / 2));
    margin-inline-start: auto;
  }
}

/* =========================================================
   Product
   ========================================================= */
.section--product { background: var(--c-bg-elev); }
.product__media picture { display: block; }
.product__media img {
  width: 100%;
  max-width: 560px;
  margin-inline: auto;
}
.product__tag {
  display: inline-block;
  margin-block-end: var(--s-3);
}
.product__tag span {
  display: inline-block;
  padding: 0.4em 1em;
  background: var(--c-accent);
  color: var(--c-accent-ink);
  font-weight: 700;
  font-size: var(--fs-sm);
  letter-spacing: 0.08em;
}
.product__lead {
  font-size: var(--fs-lead);
  font-weight: 700;
  margin-block-end: var(--s-3);
  color: var(--c-fg);
}
.product__body p + p { margin-block-start: 1.2em; }
.product__badges {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-1);
  margin-block-start: var(--s-4);
}
.product__badges li {
  padding: 0.4em 0.9em;
  border: 1px solid var(--c-border);
  font-size: var(--fs-sm);
  letter-spacing: 0.06em;
  color: var(--c-fg-muted);
}

/* =========================================================
   Feature number badge (No.1〜3)
   ========================================================= */
.feature-no {
  display: inline-block;
  padding: 0.2em 0.7em 0.25em;
  background: var(--c-accent);
  color: var(--c-accent-ink);
  font-family: var(--ff-sans);
  font-weight: 700;
  letter-spacing: 0.1em;
  font-size: var(--fs-sm);
  margin-block-end: var(--s-3);
}

/* =========================================================
   Problem (No.1)
   ========================================================= */
.section--problem { background: var(--c-bg-elev2); }
.section--problem .section__bg img {
  object-fit: contain;
  object-position: right center;
  opacity: 0.6;
}
.section--problem .section__bg--right::after {
  background: linear-gradient(90deg, rgba(20,20,20,0.95) 0%, rgba(20,20,20,0.55) 55%, rgba(20,20,20,0.2) 100%);
}
.section--problem .section__title em {
  color: var(--c-accent-text);
  font-size: 1.15em;
}
.problem__grid {
  display: grid;
  gap: var(--s-5);
  grid-template-columns: 1fr;
  margin-block-start: var(--s-5);
}
@container (min-width: 760px) {
  .problem__grid { grid-template-columns: 1fr 1fr; gap: var(--s-6); align-items: start; }
}
.problem__lead p { color: var(--c-fg); }
.problem__lead p + p { margin-block-start: 1.2em; }
.problem__chain-label {
  display: inline-block;
  margin-block-start: var(--s-3) !important;
  padding: 0.4em 1em;
  border: 1px solid var(--c-accent-text);
  color: var(--c-accent-text);
  font-weight: 700;
  letter-spacing: 0.1em;
  font-size: var(--fs-sm);
}
.problem__list {
  counter-reset: problem;
  border-block-start: 1px solid var(--c-border);
}
.problem__list li {
  counter-increment: problem;
  position: relative;
  padding: 0.85rem 0 0.85rem 3rem;
  border-block-end: 1px solid var(--c-border);
  font-weight: 500;
}
.problem__list li::before {
  content: counter(problem, decimal-leading-zero);
  position: absolute;
  inset-inline-start: 0;
  inset-block-start: 0.85rem;
  color: var(--c-accent-text);
  font-weight: 700;
  letter-spacing: 0.05em;
  font-feature-settings: "tnum";
}
.problem__list li:last-child {
  color: var(--c-accent-text);
  font-weight: 700;
}

/* =========================================================
   Solution (No.2)
   ========================================================= */
.solution__head .section__title em {
  display: inline-block;
  padding-inline: 0.15em;
  background: linear-gradient(transparent 60%, color-mix(in srgb, var(--c-accent) 35%, transparent) 60%);
  color: var(--c-fg);
}
.solution__head p + p { margin-block-start: 1.2em; }
.point-list {
  display: grid;
  gap: var(--s-2);
}
.point-list li {
  padding: var(--s-3);
  background: var(--c-bg-elev);
  border-inline-start: 3px solid var(--c-accent);
  position: relative;
  counter-increment: point;
}
.point-list { counter-reset: point; }
.point-list li::before {
  content: counter(point, decimal-leading-zero);
  position: absolute;
  inset-block-start: var(--s-2);
  inset-inline-end: var(--s-3);
  font-size: var(--fs-sm);
  color: var(--c-accent-text);
  font-weight: 700;
  letter-spacing: 0.1em;
}
.point-list__title {
  font-size: var(--fs-h3);
  font-weight: 700;
  color: var(--c-fg);
  margin-block-end: var(--s-1);
}
.point-list__body { color: var(--c-fg-muted); font-size: var(--fs-sm); }
.solution__note {
  margin-block-start: var(--s-3);
  font-size: var(--fs-sm);
  color: var(--c-fg-muted);
}
.solution__addendum {
  margin-block-start: var(--s-6);
  padding-block-start: var(--s-5);
  border-block-start: 1px solid var(--c-border);
  max-width: 920px;
}
.comparison {
  display: grid;
  gap: var(--s-5);
}
.comparison__item {
  padding: var(--s-4) var(--s-3);
  background: var(--c-bg-elev);
  border-inline-start: 3px solid var(--c-accent);
}
.comparison__item .comparison__eyebrow {
  font-size: var(--fs-eyebrow);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  font-weight: 700;
  color: var(--c-accent-text);
  margin-block-end: var(--s-1);
}
.comparison__title {
  font-size: var(--fs-h3);
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-fg);
  margin-block-end: var(--s-3);
}
.comparison__title em {
  font-style: normal;
  display: inline-block;
  padding-inline: 0.15em;
  background: linear-gradient(transparent 60%, color-mix(in srgb, var(--c-accent) 35%, transparent) 60%);
}
.comparison__item p { color: color-mix(in srgb, var(--c-fg) 92%, var(--c-fg-muted)); }
.comparison__item p + p { margin-block-start: 1.1em; }
.comparison__item strong {
  color: var(--c-accent-text);
  font-weight: 700;
}
.comparison__lead {
  font-size: var(--fs-lead);
  font-weight: 500;
  color: var(--c-fg) !important;
  padding-inline-start: var(--s-3);
  border-inline-start: 2px solid color-mix(in srgb, var(--c-accent) 60%, transparent);
}
.comparison__closer {
  margin-block-start: var(--s-4) !important;
  padding-block-start: var(--s-3);
  border-block-start: 1px solid var(--c-border);
  font-size: var(--fs-lead);
  font-weight: 700;
  color: var(--c-fg) !important;
  text-align: center;
  letter-spacing: 0.04em;
}

/* =========================================================
   Mechanism (No.3)
   ========================================================= */
.section--mechanism .section__bg img { opacity: 0.35; }
.section--mechanism .section__inner { max-width: 760px; }
.mechanism__keyword {
  font-family: "Noto Sans", system-ui, sans-serif;
  font-size: var(--fs-display);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: 0.01em;
  color: color-mix(in srgb, var(--c-fg) 70%, transparent);
  margin-block-end: var(--s-4);
  font-style: italic;
}

/* =========================================================
   Made in Japan
   ========================================================= */
.section--madein .section__title {
  font-size: clamp(1.625rem, 1.25rem + 1.4vw, 2.375rem);
  line-height: 1.5;
  margin-block-end: var(--s-4);
}
.madein__media {
  margin: 0;
}
.madein__media picture { display: block; }
.madein__media img {
  width: 100%;
  height: auto;
  border: 1px solid var(--c-border);
  background: var(--c-bg-elev);
}
.madein__list {
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
}
.madein__item {
  position: relative;
  padding: var(--s-2) var(--s-3);
  background: var(--c-bg-elev);
  border: 1px solid var(--c-border);
  border-inline-start: 3px solid var(--c-accent);
  display: grid;
  grid-template-columns: auto 1fr;
  column-gap: var(--s-3);
  row-gap: 0.3em;
  align-items: baseline;
}
.madein__region {
  grid-row: 1 / span 2;
  align-self: center;
  font-size: var(--fs-h3);
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--c-fg);
  line-height: 1.1;
  padding-inline-end: var(--s-3);
  border-inline-end: 1px solid var(--c-border);
}
.madein__theme {
  font-size: var(--fs-sm);
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--c-accent-text);
  line-height: 1.3;
}
.madein__desc {
  font-size: var(--fs-sm);
  line-height: 1.7;
  color: color-mix(in srgb, var(--c-fg) 92%, var(--c-fg-muted));
}
.madein__badge {
  margin-block-start: var(--s-3);
  text-align: end;
  opacity: 0.85;
}
.madein__badge img {
  display: inline-block;
  width: clamp(126px, 12vw, 162px);
  height: auto;
}
@media (max-width: 720px) {
  .madein__item {
    grid-template-columns: 1fr;
    row-gap: 0.4em;
  }
  .madein__region {
    grid-row: auto;
    padding-inline-end: 0;
    border-inline-end: 0;
    padding-block-end: 0.4em;
    border-block-end: 1px solid var(--c-border);
  }
  .madein__badge { text-align: center; }
}

/* =========================================================
   Closing
   ========================================================= */
.section--closing { padding-block: var(--s-7); }
.section--closing .section__bg img { opacity: 0.5; }
.section--closing .section__bg::after {
  background: linear-gradient(90deg, rgba(10,10,10,0.95) 0%, rgba(10,10,10,0.7) 100%);
}
.section--closing .section__inner { max-width: 720px; }
.closing__keyword {
  font-family: "Noto Sans", system-ui, sans-serif;
  font-size: var(--fs-display);
  font-weight: 700;
  line-height: 0.95;
  color: var(--c-accent-text);
  margin-block-end: var(--s-5);
  letter-spacing: 0.01em;
  font-style: italic;
}

/* =========================================================
   Notice
   ========================================================= */
.section--notice {
  padding-block: var(--s-5);
  border-block-start: 1px solid var(--c-border);
}
.section--notice .section__inner { max-width: 880px; }
.notice__title {
  font-size: var(--fs-base);
  font-weight: 700;
  color: var(--c-fg);
  letter-spacing: 0.04em;
  margin-block-end: var(--s-3);
  padding-inline-start: var(--s-2);
  border-inline-start: 2px solid var(--c-accent);
}
.notice__list {
  list-style: none;
  padding-inline-start: 0;
  margin: 0;
}
.notice__list li {
  position: relative;
  padding-inline-start: 1.5em;
  font-size: var(--fs-sm);
  color: var(--c-fg-muted);
  line-height: 1.75;
}
.notice__list li + li { margin-block-start: 0.6em; }
.notice__list li::before {
  content: "—";
  position: absolute;
  inset-inline-start: 0;
  color: var(--c-fg-muted);
}
.notice__list strong {
  color: var(--c-fg);
  font-weight: 700;
}

/* =========================================================
   Footer
   ========================================================= */
.site-footer {
  border-block-start: 1px solid var(--c-border);
  padding-block: var(--s-5);
  background: var(--c-bg);
}
.site-footer__inner {
  max-width: var(--container);
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--s-3);
}
.site-footer__brand img { height: 40px; width: auto; }
.site-footer__copy { color: var(--c-fg-muted); font-size: var(--fs-sm); letter-spacing: 0.06em; }

/* =========================================================
   Reveal animation (subtle)
   ========================================================= */
@media (prefers-reduced-motion: no-preference) {
  .section__inner > * { opacity: 1; }
  [data-reveal] {
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 700ms var(--ease), transform 700ms var(--ease);
  }
  [data-reveal][data-revealed="true"] {
    opacity: 1;
    transform: none;
  }
}