@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@300;400;500;700&family=Noto+Serif+JP:wght@400;500;600;700&display=swap');

*,
*::before,
*::after { box-sizing: border-box; }

:root {
  --violet: #6514ff;
  --magenta: #bf00ff;
  --ink: #1c1726;
  --paper: #fdfbff;
  --tint: #f4edff;
  --body: #eae4f7;
  --muted: #b3a6cf;
  --line: rgba(255, 255, 255, .12);
  --edge: 10px;
}

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

body {
  margin: 0;
  background-color: var(--ink);
  background-image:
    radial-gradient(circle at 6% -8%, rgba(191, 0, 255, .34), transparent 42%),
    radial-gradient(circle at 94% 2%, rgba(101, 20, 255, .4), transparent 46%);
  background-attachment: fixed;
  color: var(--body);
  font-family: "Noto Sans JP", system-ui, -apple-system, "Hiragino Kaku Gothic ProN", "Microsoft YaHei", sans-serif;
  font-size: 17px;
  font-weight: 400;
  line-height: 1.8;
  letter-spacing: .01em;
}

img { max-width: 100%; }

a { color: inherit; }

/* ---------- 页头：品牌行 / 菜单行 ---------- */

.site-head {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(28, 23, 38, .94);
  border-bottom: 2px solid rgba(191, 0, 255, .5);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.head-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 10px 20px 8px;
}

.brand-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  padding: 2px 0;
  color: #fff;
  text-decoration: none;
  font-family: "Noto Serif JP", "Noto Sans JP", serif;
  font-weight: 700;
  font-size: 20px;
  letter-spacing: .05em;
}

.brand-glyph {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  background: linear-gradient(135deg, var(--violet), var(--magenta));
  color: #fff;
  font-size: 17px;
  line-height: 1;
}

.brand-img {
  display: block;
  width: 36px;
  height: 36px;
  border-radius: 9px;
  object-fit: cover;
}

.brand-name { white-space: nowrap; }

.cta {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 20px;
  background: var(--magenta);
  color: #fff;
  text-decoration: none;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .06em;
  clip-path: polygon(10px 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
  transition: background .22s ease, transform .22s ease;
}

.cta:hover,
.cta:focus-visible {
  background: var(--violet);
  transform: translateY(-2px);
}

.head-menu { margin-top: 2px; }

.head-menu > summary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 2px;
  list-style: none;
  color: #d9cbff;
  font-size: 16px;
  letter-spacing: .16em;
  cursor: pointer;
  user-select: none;
}

.head-menu > summary::-webkit-details-marker { display: none; }

.head-menu > summary::after {
  content: "";
  width: 0;
  height: 0;
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-top: 6px solid var(--magenta);
  transition: transform .22s ease;
}

.head-menu[open] > summary::after { transform: rotate(180deg); }

.head-menu > menu {
  display: flex;
  flex-wrap: wrap;
  gap: 2px 4px;
  margin: 4px 0 8px;
  padding: 0;
  list-style: none;
}

.head-menu a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  border-radius: var(--edge);
  border-bottom: 3px solid transparent;
  color: #cfc5e6;
  text-decoration: none;
  font-size: 16px;
  transition: color .2s ease, background .2s ease, border-color .2s ease;
}

.head-menu a:hover,
.head-menu a:focus-visible {
  color: #fff;
  background: rgba(101, 20, 255, .55);
  border-bottom-color: var(--magenta);
}

/* ---------- 主区 ---------- */

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 26px 20px 60px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 288px;
  gap: 46px;
  align-items: start;
}

div {
  background: var(--paper);
  color: #241d33;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 26px 60px rgba(0, 0, 0, .5);
}

/* ---------- 首屏 ---------- */

.hero {
  position: relative;
  isolation: isolate;
  min-height: 45vh;
  display: grid;
  grid-template-columns: 1.2fr .8fr;
  align-items: center;
  gap: 18px;
  padding: 32px 32px 62px;
  background: var(--ink);
  color: #fff;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    radial-gradient(circle at 78% 18%, rgba(191, 0, 255, .6), transparent 54%),
    repeating-linear-gradient(135deg, rgba(101, 20, 255, .32) 0 16px, transparent 16px 38px);
  background-size: auto, 240% 240%;
  animation: drift 20s linear infinite;
}

@keyframes drift {
  from { background-position: 0 0, 0 0; }
  to { background-position: 0 0, 240% 240%; }
}

.hero-h1 {
  margin: 0;
  font-family: "Noto Serif JP", "Noto Sans JP", serif;
  font-size: clamp(30px, 4.6vw, 56px);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: .01em;
  text-shadow: 0 8px 30px rgba(0, 0, 0, .45);
}

.hero-h1 > span {
  display: inline;
  background-image: linear-gradient(transparent 62%, rgba(191, 0, 255, .95) 62%, rgba(191, 0, 255, .95) 88%, transparent 88%);
}

.hero-art {
  position: relative;
  min-height: 196px;
}

.hero-art::before {
  content: "";
  position: absolute;
  inset: 12% 8% 4% 12%;
  border-radius: var(--edge);
  background: linear-gradient(150deg, var(--violet), var(--magenta));
  clip-path: polygon(0 10%, 100% 0, 92% 100%, 6% 92%);
  opacity: .85;
}

.shot {
  position: absolute;
  object-fit: cover;
  border-radius: var(--edge);
  border: 4px solid #fff;
  box-shadow: 0 16px 36px rgba(0, 0, 0, .55);
}

.shot-a {
  width: 62%;
  left: 2%;
  top: 0;
  transform: rotate(-4deg);
}

.shot-b {
  width: 50%;
  right: 0;
  bottom: 0;
  transform: rotate(5deg);
  border-color: var(--magenta);
}

.hero-band {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 34px;
  background: linear-gradient(90deg, var(--violet), var(--magenta));
  clip-path: polygon(0 58%, 100% 0, 100% 100%, 0 100%);
}

/* ---------- 正文区块 ---------- */

div > section:not(.hero) {
  padding: 36px 32px;
  scroll-margin-top: 128px;
}

div > section:not(.hero) + section:not(.hero) {
  border-top: 1px solid rgba(101, 20, 255, .16);
}

div > section:not(.hero):nth-child(even) {
  background: var(--tint);
}

div h2 {
  margin: 0 0 16px;
  font-family: "Noto Serif JP", "Noto Sans JP", serif;
  font-size: clamp(23px, 2.5vw, 31px);
  font-weight: 700;
  line-height: 1.36;
  color: var(--ink);
}

div h2 > span {
  display: inline;
  background-image: linear-gradient(transparent 72%, rgba(191, 0, 255, .42) 72%);
}

div h3,
div h4 {
  margin: 24px 0 10px;
  font-size: 20px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--violet);
}

div h3 > span,
div h4 > span {
  display: inline;
  border-bottom: 3px solid var(--magenta);
  padding-bottom: 2px;
}

div p { margin: 0 0 16px; }

div strong { color: var(--ink); font-weight: 700; }

div a {
  color: var(--violet);
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}

div a:hover { color: var(--magenta); }

div ul,
div ol {
  margin: 0 0 18px;
  padding: 0;
  list-style: none;
}

div ol { counter-reset: step; }

div ul > li {
  position: relative;
  margin: 0 0 14px;
  padding: 15px 18px 15px 40px;
  background: #fff;
  border-radius: var(--edge);
  border-bottom: 3px solid var(--magenta);
  box-shadow: 0 6px 16px rgba(28, 23, 38, .08);
}

div ul > li::before {
  content: "";
  position: absolute;
  left: 18px;
  top: 24px;
  width: 10px;
  height: 10px;
  background: var(--violet);
  transform: rotate(45deg);
}

div ol > li {
  position: relative;
  margin: 0 0 14px;
  padding: 15px 18px 15px 48px;
  background: #fff;
  border-radius: var(--edge);
  border-bottom: 3px solid var(--violet);
  box-shadow: 0 6px 16px rgba(28, 23, 38, .08);
  counter-increment: step;
}

div ol > li::before {
  content: counter(step);
  position: absolute;
  left: 14px;
  top: 14px;
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  border-radius: 7px;
  background: var(--magenta);
  color: #fff;
  font-size: 14px;
  font-weight: 700;
}

div blockquote {
  margin: 0 0 18px;
  padding: 16px 20px;
  background: #fff;
  border-left: 6px solid var(--magenta);
  border-radius: var(--edge);
  color: #3a3050;
}

div blockquote p:last-child { margin-bottom: 0; }

div figure {
  margin: 0 0 18px;
  padding: 10px;
  background: #fff;
  border-radius: var(--edge);
  border-bottom: 3px solid var(--violet);
}

div figure img { border-radius: 8px; display: block; }

div figcaption {
  font-size: 15px;
  color: #6b6180;
  padding-top: 8px;
}

div table {
  display: block;
  width: 100%;
  overflow-x: auto;
  border-collapse: collapse;
  margin: 0 0 18px;
  font-size: 16px;
}

div th,
div td {
  border: 1px solid rgba(101, 20, 255, .22);
  padding: 10px 12px;
  text-align: left;
}

div th { background: var(--tint); color: var(--ink); }

div code {
  font-size: 15px;
  background: rgba(101, 20, 255, .1);
  padding: 1px 5px;
  border-radius: 5px;
}

/* ---------- 侧栏 ---------- */

.side {
  position: sticky;
  top: 132px;
  padding: 18px 18px 22px;
  background: #251d38;
  border-top: 6px solid var(--magenta);
  border-radius: 12px;
  box-shadow: 0 20px 46px rgba(0, 0, 0, .42);
}

.side-title {
  margin: 0 0 12px;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .16em;
  color: #fff;
  font-family: "Noto Sans JP", sans-serif;
}

.side-title > span {
  display: inline-block;
  padding-bottom: 6px;
  border-bottom: 2px solid var(--violet);
}

.side-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.side-list li + li { border-top: 1px solid var(--line); }

.side-list a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 4px 2px;
  color: #d8cdf2;
  text-decoration: none;
  font-size: 16px;
  transition: color .2s ease, background .2s ease, padding .2s ease;
}

.side-list a:hover,
.side-list a:focus-visible {
  color: #fff;
  padding-left: 10px;
  background: rgba(101, 20, 255, .4);
  border-radius: 8px;
}

/* ---------- 页脚 ---------- */

.site-foot {
  max-width: 1200px;
  margin: 0 auto;
  padding: 16px 20px 46px;
  border-top: 2px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 18px;
}

.site-foot p {
  margin: 0;
  font-size: 15px;
  color: var(--muted);
  letter-spacing: .04em;
}

.foot-brand {
  color: #fff;
  font-weight: 700;
}

.site-foot small { font-size: 16px; }

.site-foot small a {
  display: inline-block;
  min-height: 40px;
  padding: 8px 2px;
  color: #d8cdf2;
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color .2s ease, border-color .2s ease;
}

.site-foot small a + a { margin-left: 18px; }

.site-foot small a:hover,
.site-foot small a:focus-visible {
  color: #fff;
  border-bottom-color: var(--magenta);
}

/* ---------- 滚动进入 ---------- */

html.js div > section,
html.js .side li {
  opacity: 0;
  transform: translateY(16px);
}

html.js div > section.in,
html.js .side li.in {
  opacity: 1;
  transform: none;
  transition: opacity .42s ease, transform .42s ease;
}

html.js .side li:nth-child(1) { transition-delay: .03s; }
html.js .side li:nth-child(2) { transition-delay: .08s; }
html.js .side li:nth-child(3) { transition-delay: .13s; }
html.js .side li:nth-child(4) { transition-delay: .18s; }
html.js .side li:nth-child(5) { transition-delay: .23s; }
html.js .side li:nth-child(6) { transition-delay: .28s; }

/* ---------- 断点 ---------- */

@media (max-width: 879px) {
  body { font-size: 16px; }

  .head-inner { padding: 8px 14px 6px; }

  .brand { font-size: 19px; }

  main {
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
    padding: 16px 14px 44px;
  }

  .hero {
    grid-template-columns: minmax(0, 1fr);
    min-height: 0;
    padding: 26px 20px 56px;
  }

  .hero-art {
    min-height: 168px;
    margin-top: 20px;
  }

  div > section:not(.hero) {
    padding: 26px 20px;
    scroll-margin-top: 96px;
  }

  .side {
    position: static;
    order: 2;
  }

  .site-foot { padding: 14px 14px 38px; }
}

@media (max-width: 380px) {
  .cta { padding: 0 14px; }
  .head-menu a { padding: 0 10px; }
  .brand { font-size: 18px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .hero::before { animation: none; }
  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    transition-duration: .01ms !important;
  }
  html.js div > section,
  html.js .side li {
    opacity: 1;
    transform: none;
  }
}

button[aria-expanded]{min-width:44px;min-height:44px}