:root {
  --orange: #e86f00;
  --orange-hover: #ce6100;
  --orange-soft: #fff0d6;
  --orange-ink: #3a1c00;
  --charcoal-950: #141414;
  --charcoal-900: #1a1a1a;
  --charcoal-800: #252525;
  --charcoal-700: #3a3a3a;
  --ink-900: #171717;
  --ink-700: #464646;
  --ink-500: #6b6b6b;
  --line: #dfddd4;
  --paper: #faf9f4;
  --white: #fff;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink-900);
  background: var(--white);
  font-family: Inter, "Helvetica Neue", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  line-height: 1.65;
}

a {
  color: inherit;
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: -5rem;
  left: 1rem;
  padding: 0.75rem 1rem;
  color: var(--white);
  background: var(--charcoal-950);
}

.skip-link:focus {
  top: 1rem;
}

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 78px;
  padding: 0 5vw;
  border-bottom: 1px solid var(--line);
  background: rgb(255 255 255 / 95%);
  backdrop-filter: blur(10px);
}

.brand img {
  display: block;
  width: 176px;
  height: auto;
}

nav {
  display: flex;
  align-items: center;
  gap: 2rem;
  font-size: 0.875rem;
  font-weight: 650;
}

nav a {
  text-decoration: none;
}

nav a:hover,
nav a:focus-visible {
  color: var(--orange-ink);
}

.nav-cta {
  padding: 0.55rem 0.9rem;
  background: var(--orange);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 0.65fr);
  align-items: center;
  gap: 8vw;
  min-height: 680px;
  padding: 7rem max(5vw, calc((100vw - var(--max)) / 2));
  overflow: hidden;
  background: var(--paper);
}

.hero__content {
  min-width: 0;
  max-width: 720px;
}

.eyebrow {
  margin: 0 0 1.25rem;
  color: var(--orange-ink);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.2em;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 1.75rem;
  font-size: clamp(3.5rem, 7vw, 6.75rem);
  line-height: 0.94;
  letter-spacing: -0.055em;
}

.hero__lead {
  max-width: 650px;
  margin-bottom: 2.25rem;
  color: var(--ink-700);
  font-size: clamp(1.1rem, 2vw, 1.35rem);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 52px;
  padding: 0.75rem 1.5rem;
  border: 1px solid var(--charcoal-900);
  font-weight: 750;
  text-decoration: none;
}

.button--primary {
  color: var(--charcoal-950);
  background: var(--orange);
}

.button--primary:hover {
  background: var(--orange-hover);
}

.button--secondary {
  color: var(--charcoal-900);
  background: transparent;
}

.button--secondary:hover {
  background: var(--white);
}

.button--light {
  color: var(--white);
  border-color: var(--charcoal-950);
  background: var(--charcoal-950);
}

.market-note {
  margin: 1.5rem 0 0;
  color: var(--ink-500);
  font-size: 0.9rem;
}

.domain-mark {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  width: min(360px, 34vw);
  aspect-ratio: 1;
  transform: rotate(-3deg);
}

.domain-mark span {
  background: var(--orange);
}

.domain-mark .is-accent {
  background: var(--charcoal-900);
}

.section {
  padding: 7rem max(5vw, calc((100vw - var(--max)) / 2));
}

.section-heading {
  max-width: 720px;
  margin-bottom: 4rem;
}

h2 {
  margin-bottom: 1rem;
  font-size: clamp(2.25rem, 4vw, 4rem);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.section-heading > p:last-child {
  color: var(--ink-700);
  font-size: 1.12rem;
}

.section--materials {
  background: var(--paper);
}

.reference-notice {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.25rem;
  margin: -1.5rem 0 2rem;
  padding: 1rem 1.25rem;
  color: var(--charcoal-900);
  border-left: 3px solid var(--orange);
  background: var(--white);
  font-size: 0.84rem;
}

.reference-notice strong {
  white-space: nowrap;
}

.material-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  grid-auto-rows: 1fr;
}

.material-card {
  display: flex;
  flex-direction: column;
  min-height: 350px;
  padding: 2rem;
  border: 1px solid var(--line);
  background: var(--white);
}

.material-card__meta {
  margin-bottom: 1rem;
  color: var(--orange-ink);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.14em;
}

.material-card h3 {
  margin-bottom: 0.65rem;
  font-size: 1.35rem;
}

.material-card > p:not(.material-card__meta) {
  color: var(--ink-700);
}

.material-specs {
  display: grid;
  gap: 0.65rem;
  margin: auto 0 0;
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
  font-size: 0.82rem;
}

.material-specs div {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
}

.material-specs dt {
  color: var(--ink-500);
}

.material-specs dd {
  margin: 0;
  font-weight: 650;
  text-align: right;
}

.selection-guide {
  display: grid;
  grid-template-columns: minmax(240px, 0.7fr) minmax(0, 1.3fr);
  gap: 5rem;
  align-items: start;
  margin-top: 7rem;
}

.selection-guide__intro {
  max-width: 430px;
}

.selection-guide__intro h2 {
  font-size: clamp(2rem, 3.5vw, 3.35rem);
}

.selection-guide__intro > p:last-child {
  color: var(--ink-700);
}

.selection-table-wrap {
  min-width: 0;
  overflow-x: auto;
  border: 1px solid var(--line);
  background: var(--white);
}

.selection-table-wrap:focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 3px;
}

.selection-table__title {
  display: flex;
  justify-content: space-between;
  min-width: 560px;
  padding: 1.2rem 1.35rem;
  color: var(--charcoal-900);
  border-bottom: 1px solid var(--line);
  background: var(--orange-soft);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.selection-table__title sub,
table sub {
  font-size: 0.72em;
}

table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
}

caption {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

th,
td {
  padding: 1rem 1.35rem;
  border-bottom: 1px solid var(--line);
  text-align: left;
}

thead th {
  color: var(--ink-700);
  background: var(--paper);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

tbody th {
  font-weight: 700;
}

tbody td {
  font-family: "SFMono-Regular", Consolas, monospace;
  text-align: right;
}

thead th:not(:first-child) {
  text-align: right;
}

table sup,
.selection-note sup {
  color: var(--orange-ink);
  font-weight: 800;
}

.selection-note {
  min-width: 560px;
  margin: 0;
  padding: 1rem 1.35rem;
  color: var(--ink-700);
  background: var(--paper);
  font-size: 0.78rem;
}

.card-grid,
.principles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}

.card {
  min-height: 270px;
  padding: 2rem;
  border: 1px solid var(--line);
  border-right-width: 0;
}

.card:last-child {
  border-right-width: 1px;
}

.card__number,
.principles span {
  color: var(--orange-ink);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.8rem;
  font-weight: 700;
}

.card h3,
.principles h3 {
  margin: 3rem 0 1rem;
  font-size: 1.35rem;
}

.card p,
.principles p {
  color: var(--ink-700);
}

.section--dark {
  color: var(--white);
  background: var(--charcoal-950);
}

.section--dark .eyebrow,
.section--dark .principles span {
  color: var(--orange);
}

.section--dark .section-heading > p:last-child,
.section--dark .principles p {
  color: #d6d6d6;
}

.principles > div {
  padding: 2rem 2rem 1rem 0;
  border-top: 1px solid #484848;
}

.contact {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 3rem;
  padding: 6rem max(5vw, calc((100vw - var(--max)) / 2));
  color: var(--charcoal-950);
  background: var(--orange);
}

.contact > div {
  max-width: 730px;
}

.contact .eyebrow {
  color: var(--orange-ink);
}

.contact h2 {
  font-size: clamp(2rem, 4vw, 3.5rem);
}

.contact p:last-child {
  margin-bottom: 0;
  color: var(--charcoal-900);
}

footer {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: center;
  gap: 3rem;
  padding: 2.5rem 5vw;
  color: var(--ink-700);
  border-top: 1px solid var(--line);
  background: var(--paper);
  font-size: 0.82rem;
}

footer img {
  width: 150px;
}

footer p {
  margin: 0;
}

@media (max-width: 820px) {
  .site-header {
    min-height: 68px;
  }

  .brand img {
    width: 142px;
  }

  nav {
    gap: 1rem;
  }

  nav a:not(.nav-cta) {
    display: none;
  }

  .nav-cta {
    padding: 0.5rem 0.8rem;
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 5rem;
    padding-bottom: 5rem;
  }

  h1 {
    overflow-wrap: break-word;
    font-size: clamp(2.25rem, 9vw, 4.25rem);
  }

  .domain-mark {
    width: min(300px, 70vw);
    margin: 1rem auto 0;
  }

  .section,
  .contact {
    padding-top: 5rem;
    padding-bottom: 5rem;
  }

  .card-grid,
  .principles,
  .material-grid,
  .selection-guide {
    grid-template-columns: 1fr;
  }

  .material-card {
    min-height: 300px;
  }

  .selection-guide {
    gap: 2rem;
    margin-top: 5rem;
  }

  .card {
    min-height: 220px;
    border-right-width: 1px;
    border-bottom-width: 0;
  }

  .card:last-child {
    border-bottom-width: 1px;
  }

  .contact {
    align-items: flex-start;
    flex-direction: column;
  }

  footer {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }
}

@media (max-width: 1050px) {
  .selection-guide {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .selection-guide__intro {
    max-width: 720px;
  }
}

@media (min-width: 821px) and (max-width: 1050px) {
  .material-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 820px) {
  .reference-notice {
    grid-template-columns: 1fr;
    gap: 0.35rem;
  }

  .reference-notice strong {
    white-space: normal;
  }
}

@media (max-width: 600px) {
  .selection-table-wrap {
    overflow-x: visible;
  }

  .selection-table__title,
  table,
  .selection-note {
    min-width: 0;
  }

  .selection-table__title {
    padding: 1rem;
  }

  table {
    table-layout: fixed;
  }

  th,
  td {
    padding: 0.8rem 0.55rem;
  }

  thead th {
    font-size: 0.64rem;
    letter-spacing: 0.04em;
  }

  tbody th,
  tbody td {
    font-size: 0.76rem;
  }

  .selection-note {
    padding: 1rem;
  }
}

@media (max-width: 460px) {
  .hero,
  .section,
  .contact {
    padding-right: 1.25rem;
    padding-left: 1.25rem;
  }

  .actions {
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}