:root {
  --ink: #0b1530;
  --navy: #101e45;
  --blue: #426cf6;
  --cyan: #61d6e7;
  --cream: #f7f6f1;
  --paper: #fff;
  --muted: #566176;
  --line: #dce1eb;
  --font: "Noto Sans JP", sans-serif;
  --mono: "DM Mono", monospace;
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  background: var(--cream);
  color: var(--ink);
  font-family: var(--font);
  line-height: 1.8;
}
.container {
  width: min(1120px, calc(100% - 48px));
  margin: auto;
}
.skip-link {
  position: absolute;
  left: -999px;
}
.skip-link:focus {
  left: 1rem;
  top: 1rem;
  z-index: 10;
  background: #fff;
  padding: 0.5rem 1rem;
}
.site-header {
  background: rgba(247, 246, 241, 0.92);
  border-bottom: 1px solid rgba(11, 21, 48, 0.08);
  position: sticky;
  top: 0;
  z-index: 3;
  backdrop-filter: blur(12px);
}
.header-inner {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}
.brand {
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
  letter-spacing: -0.03em;
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  white-space: nowrap;
}
.brand small {
  font-family: var(--mono);
  font-size: 0.68em;
  color: var(--blue);
  letter-spacing: 0.08em;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 29px;
  height: 29px;
  border-radius: 7px;
  background: var(--blue);
  color: #fff;
  font-family: var(--mono);
  font-size: 0.9rem;
}
.site-nav {
  display: flex;
  gap: 1.8rem;
}
.site-nav a,
.text-link {
  color: var(--ink);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
}
.site-nav a:hover,
.text-link:hover {
  color: var(--blue);
}
.menu-button {
  display: none;
}
@media (max-width: 920px) {
  .site-nav {
    display: none;
    position: absolute;
    top: 76px;
    left: 0;
    right: 0;
    background: var(--cream);
    padding: 1rem 1.5rem;
    flex-direction: column;
    gap: 1rem;
    border-bottom: 1px solid var(--line);
  }
  .site-nav.is-open {
    display: flex;
  }
  .menu-button {
    display: block;
    border: 0;
    background: transparent;
    font: 600 0.82rem var(--font);
    color: var(--ink);
  }
}
.hero {
  background: var(--ink);
  color: white;
  padding: 96px 0 88px;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  align-items: center;
  gap: 6rem;
}
.eyebrow {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.13em;
  color: var(--blue);
  font-weight: 500;
  margin: 0 0 1.1rem;
}
.hero .eyebrow {
  color: var(--cyan);
}
h1,
h2,
h3,
p {
  margin-top: 0;
}
h1 {
  font-size: clamp(2.65rem, 5vw, 4.6rem);
  line-height: 1.24;
  letter-spacing: -0.07em;
  margin-bottom: 1.5rem;
}
h1 em {
  font-style: normal;
  color: var(--cyan);
}
.hero-copy {
  max-width: 570px;
  color: #c9d1e4;
  font-size: 1rem;
}
.hero-actions {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-top: 2.2rem;
}
.button {
  display: inline-flex;
  align-items: center;
  gap: 0.9rem;
  padding: 0.88rem 1.2rem;
  border-radius: 4px;
  font-weight: 700;
  text-decoration: none;
  font-size: 0.9rem;
  transition:
    transform 0.15s,
    background 0.15s;
}
.button:hover {
  transform: translateY(-2px);
}
.button-primary {
  background: var(--blue);
  color: #fff;
}
.button-secondary {
  background: var(--ink);
  color: #fff;
}
.button-light {
  background: #fff;
  color: var(--ink);
}
.hero .text-link {
  color: #fff;
  border-bottom: 1px solid rgba(255, 255, 255, 0.55);
}
.energy-card {
  padding: 28px;
  background: linear-gradient(145deg, #162959, #0f1c3e);
  border: 1px solid #3b5488;
  border-radius: 9px;
  box-shadow: 18px 20px 0 rgba(66, 108, 246, 0.22);
}
.card-label {
  font: 500 0.7rem var(--mono);
  letter-spacing: 0.12em;
  color: var(--cyan);
  margin-bottom: 1.8rem;
}
.flow-node {
  padding: 13px 15px;
  border-radius: 5px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
}
.flow-node span,
.flow-node small {
  display: block;
}
.flow-node span {
  font-weight: 700;
}
.flow-node small {
  font-size: 0.75rem;
  color: #c9d1e4;
}
.network {
  border-color: var(--cyan);
  background: rgba(97, 214, 231, 0.12);
}
.flow-arrow {
  text-align: center;
  color: var(--cyan);
  line-height: 1.35;
}
.card-note {
  font-size: 0.76rem;
  color: #bbc6df;
  margin: 1.4rem 0 0;
}
.section {
  padding: 104px 0;
}
.section-heading {
  margin-bottom: 3rem;
}
.section-heading h2 {
  font-size: clamp(2rem, 3.5vw, 3.2rem);
  letter-spacing: -0.06em;
  line-height: 1.35;
  margin: 0;
}
.section-heading.compact {
  max-width: 700px;
}
.section-heading.compact > p:last-child {
  color: var(--muted);
  margin-top: 1rem;
}
.cards {
  display: grid;
  gap: 20px;
}
.three-columns {
  grid-template-columns: repeat(3, 1fr);
}
.info-card {
  background: var(--paper);
  padding: 28px;
  min-height: 300px;
  border: 1px solid var(--line);
  border-radius: 5px;
  display: flex;
  flex-direction: column;
}
.number {
  font: 500 0.75rem var(--mono);
  color: var(--blue);
}
.info-card h3 {
  font-size: 1.25rem;
  letter-spacing: -0.04em;
  margin: 1rem 0 0.65rem;
}
.info-card p {
  color: var(--muted);
  font-size: 0.89rem;
  line-height: 1.85;
}
.info-card a {
  margin-top: auto;
  color: var(--blue);
  font-size: 0.86rem;
  font-weight: 700;
  text-decoration: none;
}
.section-tinted {
  background: #e9edf6;
}
.steps {
  list-style: none;
  margin: 0 0 2rem;
  padding: 0;
  border-top: 1px solid #c9d1e0;
}
.steps li {
  display: flex;
  gap: 2rem;
  padding: 1.5rem 0;
  border-bottom: 1px solid #c9d1e0;
}
.steps span {
  font: 500 0.9rem var(--mono);
  color: var(--blue);
}
.steps h3 {
  margin: 0;
  font-size: 1rem;
}
.steps p {
  margin: 0.25rem 0 0;
  color: var(--muted);
  font-size: 0.88rem;
}
.safety-panel {
  background: var(--blue);
  color: #fff;
  padding: clamp(28px, 5vw, 56px);
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 2rem;
  border-radius: 7px;
}
.warning-label {
  font: 500 0.7rem var(--mono);
  letter-spacing: 0.1em;
  color: #d5e1ff;
}
.safety-panel h3 {
  font-size: clamp(1.55rem, 3vw, 2.45rem);
  letter-spacing: -0.06em;
  line-height: 1.38;
  margin-bottom: 0.8rem;
}
.safety-panel p:not(.warning-label) {
  max-width: 700px;
  font-size: 0.9rem;
  color: #e7edff;
}
.glossary-preview {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  align-items: end;
  gap: 3rem;
}
.glossary-preview h2 {
  font-size: clamp(1.8rem, 3vw, 2.8rem);
  letter-spacing: -0.06em;
  line-height: 1.4;
  margin: 0;
}
.glossary-preview > p {
  font-size: 0.9rem;
  color: var(--muted);
  margin: 0;
}
.strong {
  font-size: 1rem;
}
.site-footer {
  background: var(--ink);
  color: #acb9d5;
  padding: 38px 0;
  font-size: 0.75rem;
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.footer-inner p {
  margin: 0;
}
.site-disclaimer {
  max-width: 720px;
  line-height: 1.75;
}
.site-disclaimer h2 {
  margin: 0 0 0.55rem;
  color: #fff;
  font-size: 0.9rem;
}
.site-disclaimer p + p {
  margin-top: 0.55rem;
}
.site-disclaimer-date {
  color: #d9e1f2;
}
.footer-brand {
  color: white;
}
@media (max-width: 760px) {
  .container {
    width: min(100% - 32px, 1120px);
  }
  .site-nav {
    display: none;
    position: absolute;
    top: 76px;
    left: 0;
    right: 0;
    background: var(--cream);
    padding: 1rem 1.5rem;
    flex-direction: column;
    gap: 1rem;
    border-bottom: 1px solid var(--line);
  }
  .site-nav.is-open {
    display: flex;
  }
  .menu-button {
    display: block;
    border: 0;
    background: transparent;
    font: 600 0.82rem var(--font);
    color: var(--ink);
  }
  .hero {
    padding: 64px 0;
  }
  .hero-grid,
  .three-columns,
  .glossary-preview {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .energy-card {
    max-width: 460px;
  }
  .section {
    padding: 72px 0;
  }
  .hero-actions,
  .safety-panel,
  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }
  .safety-panel {
    padding: 30px;
  }
  .steps li {
    gap: 1rem;
  }
  .glossary-preview {
    align-items: start;
  }
  .footer-inner {
    gap: 0.7rem;
  }
}
.info-card a.button-primary {
  color: #fff;
}
.info-card a.button-light {
  color: var(--ink);
}