/* =============================================
   SephirothicSystem Corporate Site
   ============================================= */

:root {
  --bg: #0b0e14;
  --bg-alt: #10141d;
  --surface: #161b26;
  --surface-2: #1c2230;
  --border: rgba(255, 255, 255, .08);
  --text: #e8ecf4;
  --text-dim: #9aa3b5;
  --accent: #6c5ce7;
  --accent-2: #00d2ff;
  --grad: linear-gradient(120deg, #6c5ce7, #00d2ff);
  --radius: 16px;
  --font-en: "Space Grotesk", "Noto Sans JP", sans-serif;
  --font-ja: "Noto Sans JP", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 90px;
}

body {
  font-family: var(--font-ja);
  font-size: 15px;
  line-height: 1.9;
  letter-spacing: .04em;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
  vertical-align: bottom;
}

ul {
  list-style: none;
}

a {
  color: var(--accent-2);
  text-decoration: none;
}

em {
  font-style: normal;
}

.inner {
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
}

.pc-only { display: inline; }
.sp-only { display: none; }

/* ---------- reveal animation ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .7s ease, transform .7s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ---------- buttons ---------- */
.btn {
  display: inline-block;
  padding: 13px 32px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .08em;
  border-radius: 999px;
  transition: transform .25s ease, box-shadow .25s ease, background .25s ease;
}

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

.btn-primary {
  color: #fff;
  background: var(--grad);
  box-shadow: 0 8px 24px rgba(108, 92, 231, .35);
}

.btn-primary:hover {
  box-shadow: 0 12px 32px rgba(0, 210, 255, .35);
}

.btn-ghost {
  color: var(--text);
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, .03);
}

.btn-ghost:hover {
  border-color: rgba(255, 255, 255, .25);
  background: rgba(255, 255, 255, .07);
}

.btn-large {
  padding: 17px 48px;
  font-size: 16px;
}

/* ---------- header ---------- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  transition: background .3s ease, box-shadow .3s ease;
}

.header.is-scrolled {
  background: rgba(11, 14, 20, .82);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  box-shadow: 0 1px 0 var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1160px;
  margin: 0 auto;
  padding: 18px 24px;
}

.header-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
}

.header-logo-mark {
  width: 14px;
  height: 14px;
  border-radius: 4px;
  background: var(--grad);
  box-shadow: 0 0 12px rgba(0, 210, 255, .6);
}

.header-logo-text {
  font-family: var(--font-en);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: .02em;
}

.header-logo-text em,
.footer-logo em {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.header-nav-list {
  display: flex;
  gap: 28px;
}

.header-nav-list a {
  position: relative;
  padding: 6px 0;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-dim);
  transition: color .25s;
}

.header-nav-list a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  border-radius: 2px;
  background: var(--grad);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .3s ease;
}

.header-nav-list a:hover {
  color: var(--text);
}

.header-nav-list a:hover::after {
  transform: scaleX(1);
}

.ext {
  font-size: 11px;
}

.nav-toggle {
  display: none;
  position: relative;
  z-index: 110;
  width: 44px;
  height: 44px;
  border: none;
  background: none;
  cursor: pointer;
}

.nav-toggle span {
  position: absolute;
  left: 10px;
  width: 24px;
  height: 2px;
  border-radius: 2px;
  background: var(--text);
  transition: transform .3s ease, opacity .3s ease, top .3s ease;
}

.nav-toggle span:nth-child(1) { top: 14px; }
.nav-toggle span:nth-child(2) { top: 21px; }
.nav-toggle span:nth-child(3) { top: 28px; }

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  top: 21px;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  top: 21px;
  transform: rotate(-45deg);
}

/* ---------- hero ---------- */
.hero {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  min-height: 100svh;
  padding: 140px 0 80px;
  overflow: hidden;
  text-align: center;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .035) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, #000 30%, transparent 100%);
  mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, #000 30%, transparent 100%);
}

.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: .45;
  animation: drift 14s ease-in-out infinite alternate;
}

.hero-orb-1 {
  top: -10%;
  left: 8%;
  width: 480px;
  height: 480px;
  background: #6c5ce7;
}

.hero-orb-2 {
  bottom: -15%;
  right: 5%;
  width: 420px;
  height: 420px;
  background: #0090c9;
  animation-delay: -7s;
}

@keyframes drift {
  from { transform: translate(0, 0) scale(1); }
  to { transform: translate(60px, 40px) scale(1.15); }
}

.hero-inner {
  position: relative;
  padding: 0 24px;
  max-width: 900px;
}

.hero-eyebrow {
  display: inline-block;
  margin-bottom: 28px;
  padding: 7px 18px;
  font-family: var(--font-en);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .22em;
  color: var(--accent-2);
  border: 1px solid rgba(0, 210, 255, .3);
  border-radius: 999px;
  background: rgba(0, 210, 255, .06);
}

.hero-title-en {
  display: block;
  font-family: var(--font-en);
  font-size: clamp(44px, 8vw, 84px);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -.01em;
}

.hero-title-ja {
  display: block;
  margin-top: 20px;
  font-size: clamp(20px, 3.4vw, 32px);
  font-weight: 900;
  letter-spacing: .06em;
}

.grad {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.hero-text {
  margin-top: 26px;
  font-size: 15px;
  color: var(--text-dim);
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-top: 40px;
  flex-wrap: wrap;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 64px;
  flex-wrap: wrap;
}

.hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.hero-stats strong {
  font-family: var(--font-en);
  font-size: 30px;
  font-weight: 700;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.hero-stats span {
  font-size: 12px;
  color: var(--text-dim);
}

.hero-scroll {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  width: 26px;
  height: 44px;
  border: 1px solid rgba(255, 255, 255, .25);
  border-radius: 999px;
}

.hero-scroll span {
  position: absolute;
  top: 8px;
  left: 50%;
  width: 4px;
  height: 8px;
  margin-left: -2px;
  border-radius: 2px;
  background: var(--accent-2);
  animation: scroll-hint 1.8s ease-in-out infinite;
}

@keyframes scroll-hint {
  0% { transform: translateY(0); opacity: 1; }
  70% { transform: translateY(16px); opacity: 0; }
  100% { transform: translateY(0); opacity: 0; }
}

/* ---------- sections ---------- */
.section {
  padding: 110px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-head {
  margin-bottom: 56px;
  text-align: center;
}

.section-label {
  font-family: var(--font-en);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: .28em;
  text-transform: uppercase;
  color: var(--accent-2);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(26px, 4vw, 36px);
  font-weight: 900;
  letter-spacing: .06em;
  line-height: 1.4;
}

.section-lead {
  margin-top: 18px;
  font-size: 14px;
  color: var(--text-dim);
}

/* ---------- cards ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 28px;
}

.card-grid-wide {
  grid-template-columns: repeat(auto-fit, minmax(300px, 460px));
  justify-content: center;
}

.card {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: transform .3s ease, border-color .3s ease, box-shadow .3s ease;
}

a.card:hover {
  transform: translateY(-6px);
  border-color: rgba(0, 210, 255, .4);
  box-shadow: 0 20px 40px rgba(0, 0, 0, .4), 0 0 0 1px rgba(0, 210, 255, .15);
}

.card-media {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 200px;
  flex-shrink: 0;
  padding: 18px;
  background: #fff;
}

.card-media img {
  max-height: 100%;
  width: auto;
  max-width: 100%;
  object-fit: contain;
}

.card-body {
  display: flex;
  flex-direction: column;
  flex: 1;
  gap: 8px;
  padding: 22px 24px 26px;
}

.card-tag {
  align-self: flex-start;
  padding: 3px 12px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--accent-2);
  border: 1px solid rgba(0, 210, 255, .3);
  border-radius: 999px;
  background: rgba(0, 210, 255, .06);
}

.card-name {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: .04em;
}

.card-info {
  font-size: 13px;
  line-height: 1.8;
  color: var(--text-dim);
}

.card-link {
  margin-top: auto;
  padding-top: 10px;
  font-size: 13px;
  font-weight: 700;
  color: var(--accent-2);
}

/* ---------- founder ---------- */
.founder {
  display: flex;
  align-items: center;
  gap: 44px;
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 48px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.founder-img {
  width: 150px;
  height: 150px;
  flex-shrink: 0;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid transparent;
  background: var(--grad) border-box;
}

.founder-name {
  font-size: 24px;
  font-weight: 900;
  letter-spacing: .08em;
}

.founder-name span {
  display: block;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .14em;
  color: var(--accent-2);
  margin-top: 2px;
}

.founder-text {
  margin: 14px 0 22px;
  font-size: 14px;
  color: var(--text-dim);
}

/* ---------- about ---------- */
.about-table {
  max-width: 760px;
  margin: 0 auto;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
}

.about-table > div {
  display: flex;
  border-bottom: 1px solid var(--border);
}

.about-table > div:last-child {
  border-bottom: none;
}

.about-table dt {
  flex: 0 0 160px;
  padding: 20px 28px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--text-dim);
  background: var(--surface-2);
}

.about-table dd {
  flex: 1;
  padding: 20px 28px;
  font-size: 14px;
}

/* ---------- contact ---------- */
.contact-panel {
  position: relative;
  overflow: hidden;
  padding: 80px 40px;
  text-align: center;
  border: 1px solid var(--border);
  border-radius: 24px;
  background:
    radial-gradient(ellipse 60% 90% at 20% 0%, rgba(108, 92, 231, .18), transparent),
    radial-gradient(ellipse 60% 90% at 80% 100%, rgba(0, 210, 255, .14), transparent),
    var(--surface);
}

.contact-panel .section-lead {
  margin-bottom: 40px;
}

/* ---------- footer ---------- */
.footer {
  padding: 56px 0 40px;
  border-top: 1px solid var(--border);
  background: var(--bg);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
}

.footer-logo {
  font-family: var(--font-en);
  font-size: 18px;
  font-weight: 700;
}

.footer-nav {
  display: flex;
  gap: 28px;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-nav a {
  font-size: 13px;
  color: var(--text-dim);
  transition: color .25s;
}

.footer-nav a:hover {
  color: var(--text);
}

.copyright {
  font-size: 12px;
  color: var(--text-dim);
}

/* ---------- subpage hero / legal ---------- */
.page-hero {
  position: relative;
  padding: 140px 0 56px;
  overflow: hidden;
}

.page-hero-brand {
  padding: 150px 0 80px;
  min-height: 58vh;
  display: flex;
  align-items: center;
}

.page-hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

.page-hero > .inner {
  position: relative;
  z-index: 1;
}

.page-hero-title {
  font-family: var(--font-en);
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 700;
  letter-spacing: .02em;
  line-height: 1.25;
  margin: 8px 0 16px;
}

.page-hero-title .hero-title-en {
  display: block;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.page-hero-lead {
  color: var(--text-dim);
  font-size: 15px;
  max-width: 640px;
  line-height: 1.9;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-item {
  padding: 28px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.feature-label {
  font-family: var(--font-en);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--accent-2);
  margin-bottom: 10px;
}

.feature-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-text {
  font-size: 14px;
  color: var(--text-dim);
  line-height: 1.8;
}

.legal-content {
  max-width: 800px;
  margin: 0 auto;
  line-height: 1.95;
}

.legal-content > p {
  margin-bottom: 1.25em;
  color: var(--text-dim);
}

.legal-content h2 {
  font-size: 18px;
  font-weight: 700;
  margin: 2.4em 0 .9em;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
  color: var(--text);
}

.legal-content ol,
.legal-content ul {
  margin: 0 0 1.25em;
  padding-left: 1.4em;
  color: var(--text-dim);
}

.legal-content ol {
  list-style: decimal;
}

.legal-content ul {
  list-style: disc;
}

.legal-content li {
  margin-bottom: 8px;
}

.legal-content li ul {
  margin: 8px 0 0;
}

.legal-content strong {
  color: var(--text);
  font-weight: 700;
}

.legal-content a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.legal-meta {
  margin-top: 3em;
  font-size: 13px;
  color: var(--text-dim);
}

.legal-nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 28px;
  margin-top: 2em;
  padding-top: 1.5em;
  border-top: 1px solid var(--border);
}

.legal-nav-links a {
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
}

.legal-nav-links a:hover {
  text-decoration: underline;
}

.brand-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 40px;
  padding: 28px 32px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.brand-banner-label {
  font-family: var(--font-en);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--accent-2);
  margin-bottom: 6px;
}

.brand-banner-title {
  font-family: var(--font-en);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 8px;
}

.brand-banner-text {
  font-size: 14px;
  color: var(--text-dim);
  line-height: 1.8;
  max-width: 640px;
}

.contact-panel .hero-actions {
  margin-top: 0;
}

/* =============================================
   media queries
   ============================================= */
@media screen and (max-width: 767px) {
  body {
    font-size: 14px;
  }

  .pc-only { display: none; }
  .sp-only { display: inline; }

  .section {
    padding: 72px 0;
  }

  .section-head {
    margin-bottom: 36px;
  }

  /* header: drawer nav */
  .nav-toggle {
    display: block;
  }

  /* backdrop-filterは固定配置の子(ドロワー)の基準を変えるためモバイルでは使わない */
  .header,
  .header.is-scrolled {
    background: rgba(11, 14, 20, .95);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
    box-shadow: 0 1px 0 var(--border);
  }

  .header-inner {
    padding: 12px 16px;
  }

  .header-nav {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(11, 14, 20, .96);
    opacity: 0;
    visibility: hidden;
    transition: opacity .3s ease, visibility .3s ease;
  }

  .header-nav.is-open {
    opacity: 1;
    visibility: visible;
  }

  .header-nav-list {
    flex-direction: column;
    align-items: center;
    gap: 30px;
  }

  .header-nav-list a {
    font-size: 17px;
    color: var(--text);
  }

  /* hero */
  .hero {
    padding: 110px 0 90px;
  }

  .hero-orb-1 { width: 300px; height: 300px; }
  .hero-orb-2 { width: 260px; height: 260px; }

  .hero-stats {
    gap: 28px;
    margin-top: 48px;
  }

  .hero-stats strong {
    font-size: 24px;
  }

  /* founder */
  .founder {
    flex-direction: column;
    text-align: center;
    padding: 36px 24px;
    gap: 24px;
  }

  /* about */
  .about-table > div {
    flex-direction: column;
  }

  .about-table dt {
    flex: none;
    padding: 12px 20px;
  }

  .about-table dd {
    padding: 14px 20px 18px;
  }

  /* contact */
  .contact-panel {
    padding: 56px 24px;
  }

  .page-hero {
    padding: 120px 0 40px;
  }

  .page-hero-brand {
    padding: 130px 0 64px;
    min-height: 0;
  }

  .feature-grid {
    grid-template-columns: 1fr;
  }

  .brand-banner {
    flex-direction: column;
    align-items: flex-start;
    padding: 24px;
  }

  .legal-content h2 {
    font-size: 16px;
  }
}