:root {
  --ink-950: #020812;
  --ink-900: #061426;
  --ink-800: #0a1c30;
  --cyan: #73e7ff;
  --cyan-soft: #dff8ff;
  --teal: #19c7bd;
  --gold: #d6a43a;
  --gold-soft: #fff2c7;
  --green: #8ff4cf;
  --rose: #e76f73;
  --white: #ffffff;
  --text: #f5f8fb;
  --muted: rgba(245, 248, 251, 0.74);
  --muted-strong: rgba(245, 248, 251, 0.88);
  --line: rgba(255, 255, 255, 0.14);
  --surface: rgba(255, 255, 255, 0.075);
  --surface-strong: rgba(255, 255, 255, 0.12);
  --shadow: 0 28px 90px rgba(0, 0, 0, 0.36);
  --glow-cyan: 0 0 42px rgba(115, 231, 255, 0.28);
  --glow-gold: 0 0 34px rgba(214, 164, 58, 0.24);
  --header-height: 76px;
  --container: 1160px;
  --section-y: clamp(72px, 9vw, 112px);
  --ease-out: cubic-bezier(0.2, 0.7, 0.18, 1);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background: var(--ink-950);
}

body {
  margin: 0;
  color: var(--text);
  background:
    linear-gradient(180deg, var(--ink-950), var(--ink-900) 42%, #07101d 100%);
  font-family:
    "Inter",
    "Helvetica Neue",
    "Arial",
    "Hiragino Sans",
    "Yu Gothic",
    "Meiryo",
    sans-serif;
  line-height: 1.75;
  overflow-x: hidden;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body.menu-open {
  overflow: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  color: inherit;
  font: inherit;
}

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

h1,
h2,
h3 {
  line-height: 1.14;
  letter-spacing: 0;
}

p {
  color: var(--muted);
}

a:focus-visible,
button:focus-visible {
  outline: 3px solid rgba(115, 231, 255, 0.9);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  left: 18px;
  top: 12px;
  z-index: 200;
  padding: 10px 14px;
  border-radius: 999px;
  color: var(--ink-950);
  background: var(--cyan);
  font-weight: 850;
  transform: translateY(-160%);
  transition: transform 0.22s ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.container {
  width: min(var(--container), calc(100% - 48px));
  margin: 0 auto;
}

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 80;
  background: rgba(2, 8, 18, 0.64);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(22px);
  transition:
    background 0.22s ease,
    border-color 0.22s ease,
    box-shadow 0.22s ease;
}

.site-header.is-scrolled {
  background: rgba(2, 8, 18, 0.9);
  border-color: rgba(115, 231, 255, 0.16);
  box-shadow: 0 20px 54px rgba(0, 0, 0, 0.28);
}

.header-inner {
  width: min(var(--container), calc(100% - 42px));
  height: var(--header-height);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}

.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}

.logo-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.34);
  background:
    radial-gradient(circle, rgba(255, 255, 255, 0.22), transparent 42%),
    linear-gradient(135deg, rgba(115, 231, 255, 0.24), rgba(214, 164, 58, 0.12));
  box-shadow: var(--glow-cyan);
}

.logo-mark span {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid var(--cyan);
  box-shadow: inset 0 0 0 3px rgba(255, 255, 255, 0.16);
}

.logo-copy {
  display: grid;
  line-height: 1.1;
}

.logo-copy strong {
  font-size: 0.96rem;
}

.logo-copy small {
  color: rgba(255, 255, 255, 0.58);
  font-size: 0.72rem;
}

.desktop-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  flex: 1 1 auto;
}

.desktop-nav a,
.header-join {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 13px;
  border-radius: 999px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 0.88rem;
  font-weight: 850;
  transition:
    color 0.2s ease,
    background 0.2s ease,
    transform 0.2s ease;
}

.desktop-nav a:hover {
  color: var(--white);
  background: rgba(255, 255, 255, 0.08);
}

.header-join {
  color: var(--ink-950);
  background: linear-gradient(135deg, var(--cyan), var(--white) 56%, var(--gold-soft));
  box-shadow: 0 16px 36px rgba(115, 231, 255, 0.22);
}

.header-join:hover {
  transform: translateY(-1px);
}

.menu-toggle,
.mobile-menu-close {
  appearance: none;
  cursor: pointer;
}

.menu-toggle {
  width: 44px;
  height: 44px;
  display: none;
  place-items: center;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.16);
  position: relative;
}

.menu-toggle span,
.mobile-menu-close span {
  position: absolute;
  width: 18px;
  height: 2px;
  border-radius: 999px;
  background: currentColor;
}

.menu-toggle span:first-child {
  transform: translateY(-4px);
}

.menu-toggle span:last-child {
  transform: translateY(4px);
}

.mobile-scrim {
  position: fixed;
  inset: 0;
  z-index: 88;
  background: rgba(0, 0, 0, 0.48);
  backdrop-filter: blur(8px);
}

.mobile-menu {
  position: fixed;
  inset: 0 0 auto auto;
  z-index: 90;
  width: min(400px, calc(100% - 18px));
  height: 100dvh;
  transform: translateX(100%);
  transition: transform 0.3s var(--ease-out);
}

.mobile-menu.is-open {
  transform: translateX(0);
}

.mobile-menu-panel {
  height: 100%;
  padding: 22px;
  border-radius: 24px 0 0 24px;
  background: linear-gradient(180deg, rgba(6, 20, 38, 0.98), rgba(2, 8, 18, 0.98));
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: -20px 0 80px rgba(0, 0, 0, 0.34);
}

.mobile-menu-top {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding-bottom: 18px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.mobile-menu-top p {
  color: var(--white);
  font-size: 0.92rem;
  font-weight: 900;
}

.mobile-menu-close {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.16);
  position: relative;
}

.mobile-menu-close span:first-child {
  transform: rotate(42deg);
}

.mobile-menu-close span:last-child {
  transform: rotate(-42deg);
}

.mobile-nav {
  display: grid;
  padding-top: 18px;
}

.mobile-nav a {
  min-height: 50px;
  display: flex;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.9);
  font-weight: 850;
}

.hero {
  min-height: 92svh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  isolation: isolate;
  padding: calc(var(--header-height) + 44px) 0 64px;
}

.hero-media {
  position: absolute;
  inset: -2%;
  z-index: -4;
  background-image: url("../images/hero.desktop.highlight.png");
  background-size: cover;
  background-position: center;
  opacity: 0.7;
}

.hero-shade {
  position: absolute;
  inset: 0;
  z-index: -3;
  background:
    linear-gradient(90deg, rgba(2, 8, 18, 0.96), rgba(2, 8, 18, 0.75) 48%, rgba(2, 8, 18, 0.54)),
    linear-gradient(180deg, rgba(2, 8, 18, 0.48), rgba(2, 8, 18, 0.96));
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -2;
  background-image:
    linear-gradient(rgba(115, 231, 255, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(115, 231, 255, 0.055) 1px, transparent 1px);
  background-size: 86px 86px;
  mask-image: linear-gradient(to bottom, black, transparent 88%);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(340px, 0.94fr);
  align-items: center;
  gap: clamp(34px, 6vw, 72px);
}

.eyebrow,
.section-label,
.panel-label {
  color: var(--cyan);
  font-size: 0.78rem;
  font-weight: 920;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.hero h1 {
  margin-top: 18px;
  color: var(--white);
  font-size: clamp(3.2rem, 7vw, 6.5rem);
  font-weight: 900;
  line-height: 0.98;
  text-shadow: 0 30px 92px rgba(0, 0, 0, 0.62);
}

.hero-subcopy {
  max-width: 760px;
  margin-top: 28px;
  color: rgba(255, 255, 255, 0.88);
  font-size: clamp(1.08rem, 1.8vw, 1.42rem);
  line-height: 1.65;
  font-weight: 720;
}

.hero-note {
  max-width: 700px;
  margin-top: 18px;
  color: rgba(255, 255, 255, 0.58);
  font-size: 0.92rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-top: 32px;
}

.button {
  min-height: 52px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 22px;
  border-radius: 999px;
  font-weight: 880;
  line-height: 1.2;
  transition:
    transform 0.22s ease,
    border-color 0.22s ease,
    background 0.22s ease,
    box-shadow 0.22s ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-primary {
  color: var(--ink-950);
  background: linear-gradient(135deg, var(--cyan), var(--white) 56%, var(--gold-soft));
  box-shadow:
    0 22px 56px rgba(115, 231, 255, 0.28),
    var(--glow-cyan);
}

.button-join {
  min-height: 58px;
  padding-inline: 28px;
  border: 1px solid rgba(255, 255, 255, 0.48);
  box-shadow:
    0 22px 60px rgba(115, 231, 255, 0.34),
    0 0 38px rgba(214, 164, 58, 0.22);
}

.button-secondary {
  color: var(--white);
  border: 1px solid rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.07);
  backdrop-filter: blur(16px);
}

.button-text {
  color: var(--cyan-soft);
  padding-inline: 8px;
}

.hero-panel,
.experience-card,
.problem-list article,
.flow-list li,
.feature-list article,
.teacher-panel,
.usecase-grid article,
.stack-list,
.cta-panel {
  border: 1px solid var(--line);
  background: var(--surface);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.hero-panel {
  padding: 14px;
  border-radius: 20px;
  background:
    linear-gradient(145deg, rgba(115, 231, 255, 0.11), rgba(214, 164, 58, 0.07)),
    rgba(255, 255, 255, 0.075);
}

.mock-toolbar {
  display: flex;
  gap: 7px;
  padding: 8px 8px 14px;
}

.mock-toolbar span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.34);
}

.live-card {
  min-height: 400px;
  padding: clamp(22px, 4vw, 34px);
  border-radius: 14px;
  background:
    linear-gradient(180deg, rgba(2, 8, 18, 0.58), rgba(2, 8, 18, 0.86)),
    radial-gradient(circle at 20% 20%, rgba(115, 231, 255, 0.18), transparent 42%);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.live-card h2 {
  max-width: 440px;
  margin-top: 14px;
  color: var(--white);
  font-size: clamp(1.7rem, 3.2vw, 3rem);
}

.comment-stream {
  display: grid;
  gap: 12px;
  margin-top: 32px;
}

.comment-stream p {
  padding: 14px 16px;
  border-radius: 12px;
  color: rgba(255, 255, 255, 0.86);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.section {
  padding: var(--section-y) 0;
}

.section[id] {
  scroll-margin-top: calc(var(--header-height) + 24px);
}

.section-alt {
  background: rgba(255, 255, 255, 0.025);
  border-block: 1px solid rgba(255, 255, 255, 0.06);
}

.section-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(28px, 6vw, 72px);
}

.section-heading h2 {
  max-width: 900px;
  margin-top: 14px;
  color: var(--white);
  font-size: clamp(2rem, 4.2vw, 4rem);
  font-weight: 880;
}

.section-heading p:not(.section-label),
.teacher-panel p {
  max-width: 760px;
  margin-top: 22px;
  font-size: clamp(1rem, 1.4vw, 1.12rem);
}

.narrow {
  max-width: 880px;
}

.problem-list,
.experience-grid,
.usecase-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.problem-list article,
.experience-card,
.usecase-grid article {
  min-height: 170px;
  padding: 24px;
  border-radius: 14px;
}

.problem-list span {
  color: var(--cyan);
  font-size: 0.82rem;
  font-weight: 920;
}

.problem-list p {
  margin-top: 14px;
  color: var(--muted-strong);
  font-size: 1.08rem;
  font-weight: 760;
}

.experience-grid,
.usecase-grid {
  margin-top: 34px;
}

.experience-card h3,
.feature-list h3,
.flow-list h3,
.usecase-grid h3 {
  color: var(--white);
  font-size: 1.1rem;
}

.experience-card p,
.feature-list p,
.flow-list p,
.usecase-grid p {
  margin-top: 10px;
}

.flow-list {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 14px;
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
}

.flow-list li {
  min-height: 230px;
  display: grid;
  align-content: start;
  gap: 22px;
  padding: 22px;
  border-radius: 14px;
}

.flow-list span {
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--ink-950);
  background: linear-gradient(135deg, var(--cyan), var(--gold-soft));
  font-weight: 920;
}

.feature-list {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 14px;
  margin-top: 34px;
}

.feature-list article {
  min-height: 245px;
  padding: 22px;
  border-radius: 14px;
}

.status {
  display: inline-flex;
  margin-bottom: 12px;
  padding: 5px 10px;
  border-radius: 999px;
  color: var(--ink-950);
  font-size: 0.74rem;
  font-weight: 900;
}

.is-live {
  background: var(--green);
}

.is-dev {
  background: var(--cyan);
}

.is-plan {
  background: var(--gold-soft);
}

.teacher-panel {
  padding: clamp(24px, 4vw, 34px);
  border-radius: 16px;
}

.teacher-points {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.teacher-points span {
  padding: 8px 12px;
  border-radius: 999px;
  color: var(--cyan-soft);
  background: rgba(115, 231, 255, 0.1);
  border: 1px solid rgba(115, 231, 255, 0.22);
  font-size: 0.88rem;
  font-weight: 850;
}

.stack-list {
  display: grid;
  gap: 12px;
  padding: 26px;
  border-radius: 14px;
}

.stack-list strong {
  color: var(--cyan-soft);
}

.cta-section {
  padding-top: 0;
}

.cta-panel {
  padding: clamp(30px, 5vw, 56px);
  border-radius: 20px;
  background:
    linear-gradient(135deg, rgba(115, 231, 255, 0.14), rgba(214, 164, 58, 0.12)),
    var(--surface);
}

.cta-panel h2 {
  margin-top: 14px;
  color: var(--white);
  font-size: clamp(2rem, 4vw, 3.8rem);
}

.cta-panel p:not(.section-label) {
  max-width: 760px;
  margin-top: 18px;
}

.site-footer {
  padding: 30px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 20px;
}

.footer-inner a {
  color: var(--cyan);
  font-weight: 850;
}

[data-reveal] {
  opacity: 0;
  transform: translate3d(0, 24px, 0);
  transition:
    opacity 0.72s var(--ease-out),
    transform 0.72s var(--ease-out);
}

[data-reveal].is-visible {
  opacity: 1;
  transform: translate3d(0, 0, 0);
}

@media (max-width: 1120px) {
  .flow-list,
  .feature-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 980px) {
  .desktop-nav,
  .header-join {
    display: none;
  }

  .menu-toggle {
    display: grid;
  }

  .hero-grid,
  .section-grid {
    grid-template-columns: 1fr;
  }

  .hero-panel {
    max-width: 620px;
  }
}

@media (max-width: 680px) {
  :root {
    --header-height: 68px;
  }

  .container {
    width: min(100% - 32px, var(--container));
  }

  .header-inner {
    width: min(100% - 28px, var(--container));
  }

  .logo-copy strong {
    font-size: 0.86rem;
  }

  .hero {
    min-height: auto;
    padding-top: calc(var(--header-height) + 54px);
  }

  .hero h1 {
    font-size: clamp(3rem, 16vw, 4.5rem);
  }

  .hero-media {
    background-image: url("../images/hero.mobile.highlight.png");
    opacity: 0.58;
  }

  .hero-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .problem-list,
  .experience-grid,
  .flow-list,
  .feature-list,
  .usecase-grid {
    grid-template-columns: 1fr;
  }

  .flow-list li,
  .feature-list article,
  .problem-list article,
  .experience-card,
  .usecase-grid article {
    min-height: auto;
  }

  .live-card {
    min-height: 340px;
  }

  .footer-inner {
    display: grid;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}