:root {
  color-scheme: light;
  --background: #f4f8ff;
  --background-cool: #eaf2ff;
  --surface: rgba(255, 255, 255, 0.88);
  --text: #17243a;
  --secondary: #53627a;
  --muted: #626f81;
  --primary: #3658e8;
  --cyan: #53ddf2;
  --violet: #a967f4;
  --outline: #dce5f1;
  --shadow: 0 12px 36px rgba(65, 95, 150, 0.09);
  --radius-card: 24px;
  --content-width: 1100px;
}

* { box-sizing: border-box; }

html {
  min-width: 320px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  color: var(--text);
  background:
    radial-gradient(ellipse at 8% 0%, rgba(83, 221, 242, 0.14), transparent 29rem),
    radial-gradient(ellipse at 96% 26%, rgba(169, 103, 244, 0.09), transparent 30rem),
    var(--background);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", sans-serif;
  line-height: 1.7;
  text-rendering: optimizeLegibility;
}

a { color: var(--primary); text-underline-offset: 0.2em; }
a:hover { color: #263fbd; }
a:focus-visible {
  outline: 3px solid #3658e8;
  outline-offset: 3px;
  border-radius: 4px;
}

.shell { width: min(var(--content-width), calc(100% - 40px)); margin-inline: auto; }
.site-header { padding-block: 22px; }
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 12px; color: var(--text); text-decoration: none; }
.brand img { width: 46px; height: 46px; border-radius: 14px; object-fit: cover; box-shadow: 0 5px 18px rgba(65, 95, 150, 0.13); }
.brand-name { display: block; font-size: 1.03rem; font-weight: 750; letter-spacing: -0.025em; line-height: 1.2; }
.brand-by { display: block; margin-top: 3px; color: var(--muted); font-size: 0.78rem; }
.nav { display: flex; flex-wrap: wrap; align-items: center; justify-content: flex-end; gap: 8px 22px; }
.nav a { color: var(--secondary); font-size: 0.92rem; font-weight: 600; text-decoration: none; }
.nav a[aria-current="page"] { color: var(--primary); }

main { padding-block: 28px 76px; }
.hero { position: relative; overflow: hidden; padding: clamp(30px, 6vw, 68px); border: 1px solid rgba(220, 229, 241, 0.95); border-radius: 32px; background: linear-gradient(120deg, rgba(255,255,255,.94), rgba(255,255,255,.79) 62%, rgba(240,232,255,.62)); box-shadow: var(--shadow); }
.hero::before { position: absolute; top: -110px; right: -90px; width: 310px; height: 310px; border-radius: 50%; background: radial-gradient(circle, rgba(83,221,242,.24), rgba(71,118,245,.09) 45%, transparent 72%); content: ""; pointer-events: none; }
.hero-content { position: relative; max-width: 720px; }
.eyebrow { margin: 0 0 12px; color: var(--primary); font-size: 0.82rem; font-weight: 750; letter-spacing: 0.09em; text-transform: uppercase; }
h1, h2, h3 { line-height: 1.25; letter-spacing: -0.025em; }
h1 { margin: 0; font-size: clamp(2.2rem, 6vw, 4.2rem); }
.hero-copy { max-width: 660px; margin: 20px 0 0; color: var(--secondary); font-size: clamp(1.05rem, 2vw, 1.24rem); }
.hero-jp { margin-top: 24px; color: var(--text); font-size: clamp(1.35rem, 3vw, 1.85rem); font-weight: 700; }
.hero-en { margin: 5px 0 0; color: var(--secondary); }
.hero-links { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.button-link { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; padding: 10px 19px; border: 1px solid var(--outline); border-radius: 15px; background: rgba(255,255,255,.86); color: var(--text); font-weight: 700; text-decoration: none; box-shadow: 0 5px 16px rgba(65,95,150,.06); }
.button-link.primary { border-color: transparent; background: linear-gradient(105deg, #3658e8, #3d62de); color: #fff; }
.button-link:hover { transform: translateY(-1px); }

.page-intro { max-width: 780px; margin: 0 auto 26px; text-align: center; }
.page-intro h1 { font-size: clamp(2rem, 5vw, 3.1rem); }
.page-intro p { margin: 14px 0 0; color: var(--secondary); }
.article, .panel { border: 1px solid var(--outline); border-radius: var(--radius-card); background: var(--surface); box-shadow: var(--shadow); }
.article { max-width: 900px; margin-inline: auto; padding: clamp(22px, 5vw, 48px); }
.article section { padding-block: 20px; border-bottom: 1px solid var(--outline); }
.article section:first-child { padding-top: 0; }
.article section:last-child { padding-bottom: 0; border-bottom: 0; }
.article h2 { margin: 0 0 14px; font-size: 1.24rem; }
.article h3 { margin: 18px 0 8px; font-size: 1.04rem; }
.article p { margin: 8px 0; }
.article ul { margin: 8px 0; padding-inline-start: 1.3rem; }
.article li + li { margin-top: 5px; }
.language-block + .language-block { margin-top: 22px; padding-top: 20px; border-top: 1px dashed var(--outline); }
.language-label { margin: 0 0 8px; color: var(--muted); font-size: .74rem; font-weight: 750; letter-spacing: .08em; text-transform: uppercase; }
.updated { color: var(--muted); font-size: .88rem; }

.link-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; margin-top: 28px; }
.link-card { min-height: 155px; padding: 23px; border: 1px solid var(--outline); border-radius: 21px; background: var(--surface); color: inherit; text-decoration: none; box-shadow: var(--shadow); }
.link-card:hover { border-color: #b7c9ee; }
.link-card h2 { margin: 0 0 8px; font-size: 1.08rem; }
.link-card p { margin: 0; color: var(--secondary); font-size: .94rem; }
.faq { max-width: 900px; margin-inline: auto; }
.faq details { padding: 18px 0; border-bottom: 1px solid var(--outline); }
.faq details:first-child { padding-top: 0; }
.faq summary { color: var(--text); font-weight: 700; cursor: pointer; }
.faq details p { color: var(--secondary); }
.contact-panel { margin-top: 26px; padding: 24px; text-align: center; }
.contact-panel h2 { margin: 0 0 8px; }
.contact-panel p { margin: 6px 0; color: var(--secondary); }
.contact-email { display: inline-block; margin-top: 8px; font-size: 1.12rem; font-weight: 750; }
.site-footer { padding-block: 24px 34px; border-top: 1px solid rgba(199,213,232,.8); color: var(--muted); font-size: .86rem; }
.footer-inner { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px 24px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 18px; }
.footer-links a { color: var(--secondary); }
.not-found { text-align: center; }
.not-found p { color: var(--secondary); }

@media (max-width: 700px) {
  .shell { width: min(var(--content-width), calc(100% - 28px)); }
  .header-inner { align-items: flex-start; flex-direction: column; gap: 17px; }
  .nav { justify-content: flex-start; gap: 8px 18px; }
  main { padding-top: 16px; }
  .hero { border-radius: 25px; }
  .link-grid { grid-template-columns: 1fr; }
  .link-card { min-height: unset; }
  .footer-inner { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}