/* ============================================
   AI-DataScience - Top Page
   ============================================ */

:root {
  --color-primary: #5b5fd6;
  --color-primary-dark: #4a4eb8;
  --color-primary-light: #7c7fe5;
  --color-text: #3d4a5c;
  --color-text-dark: #2b3543;
  --color-text-muted: #6b7785;
  --color-bg-gray: #f3f4f7;
  --color-border: #e3e6ec;
  --color-white: #ffffff;
  --gradient-purple: linear-gradient(95deg, #3D4E81 0%, #5753C9 50%, #6E7FF3 100%);
  --font-jp: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", "Meiryo", sans-serif;
  --container: 1200px;
}

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

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  font-family: var(--font-jp);
  color: var(--color-text);
  line-height: 1.7;
  font-size: 15px;
  font-weight: 400;
  background: #fff;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

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

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

/* ============================================
   Header
   ============================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  z-index: 1000;
  padding: 18px 40px;
  transition: box-shadow 0.3s ease;
}

.site-header.scrolled {
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1400px;
  margin: 0 auto;
}

.logo img {
  height: 30px;
  width: auto;
}

.global-nav {
  display: flex;
  align-items: center;
  gap: 40px;
}

.nav-link {
  font-family: "Roboto", var(--font-jp);
  font-size: 14px;
  font-weight: 700;
  line-height: 1.7;
  letter-spacing: 0.1em;
  color: var(--color-text-dark);
  position: relative;
  transition: color 0.2s;
}

.nav-link:hover {
  color: var(--color-primary);
}

.nav-link.active::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  bottom: -6px;
  height: 1.5px;
  background: currentColor;
  pointer-events: none;
}

.btn-contact-header {
  display: inline-flex;
  align-items: center;
  gap: 24px;
  background: var(--gradient-purple);
  color: #fff;
  padding: 14px 28px;
  border-radius: 4px;
  font-family: "Roboto", var(--font-jp);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.15em;
  transition: transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 4px 12px rgba(91, 95, 214, 0.3);
}

.btn-contact-header:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(91, 95, 214, 0.4);
}

.btn-contact-header .arrow-circle {
  width: 24px;
  height: 24px;
  background: rgba(255, 255, 255, 0.25);
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.btn-contact-header .arrow-circle svg {
  width: 12px;
  height: 12px;
  fill: #fff;
}

/* ============================================
   Hero
   ============================================ */
.hero {
  padding: 140px 40px 100px;
  position: relative;
  overflow: hidden;
}

.hero-inner {
  max-width: 1300px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 40px;
}

.hero-content {
  padding-left: 20px;
}

.hero-title {
  font-size: 64px;
  font-weight: 700;
  line-height: 1.4;
  background: linear-gradient(95deg, #3D4E81 0%, #5753C9 50%, #6E7FF3 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  letter-spacing: 0.02em;
  margin-bottom: 36px;
}

.hero-description {
  font-size: 15px;
  color: var(--color-text-dark);
  font-weight: 600;
  line-height: 2;
  margin-bottom: 24px;
}

.hero-author {
  font-size: 13px;
  color: var(--color-text-muted);
  margin-bottom: 36px;
  letter-spacing: 0.05em;
}

.hero-author .sep {
  margin: 0 12px;
  color: var(--color-text-muted);
}

.hero-image {
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-image img {
  max-width: 100%;
  height: auto;
}

/* ============================================
   Contact Button (large)
   ============================================ */
.btn-contact {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: 440px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 22px 28px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--color-text-dark);
  transition: all 0.25s;
  cursor: pointer;
}

.btn-contact:hover {
  border-color: var(--color-primary);
  box-shadow: 0 6px 20px rgba(91, 95, 214, 0.15);
  transform: translateY(-2px);
}

.btn-contact .arrow-circle {
  width: 32px;
  height: 32px;
  background: var(--gradient-purple);
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.btn-contact .arrow-circle svg {
  width: 14px;
  height: 14px;
  fill: #fff;
}

.btn-contact-wrapper {
  display: flex;
  justify-content: center;
  margin: 60px 0;
}

.btn-contact-wrapper .btn-contact {
  width: 300px;
  max-width: 300px;
  height: 80px;
  padding: 0 28px;
  justify-content: center;
  gap: 20px;
  font-size: 16px;
}

.hero .btn-contact {
  border: none;
  font-weight: 800;
  font-size: 18px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.15);
}

.hero .btn-contact:hover {
  border: none;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.15);
}

/* ============================================
   Section common
   ============================================ */
.section {
  padding: 100px 24px;
  position: relative;
}

.section-label {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 0.35em;
  color: #475569;
  text-align: center;
  margin-bottom: 40px;
}

.section-title {
  font-size: 44px;
  font-weight: 700;
  line-height: 1.5;
  color: #475569;
  text-align: center;
  letter-spacing: 0.04em;
  margin-bottom: 28px;
}

.identity .section-title {
  color: var(--color-text-dark);
}

.section-subtitle {
  font-size: 14px;
  color: var(--color-text-muted);
  text-align: center;
  line-height: 2;
  max-width: 900px;
  margin: 0 auto;
}

/* ============================================
   IDENTITY
   ============================================ */
.identity {
  padding-bottom: 0;
}

.identity-steps {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  margin: 90px auto 100px;
  max-width: 1100px;
  flex-wrap: wrap;
}

.identity-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  flex: 1;
  min-width: 140px;
}

.identity-step-icon {
  width: 90px;
  height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.identity-step-icon img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.identity-step-jp {
  font-size: 17px;
  font-weight: 700;
  color: var(--color-text-dark);
  margin-bottom: 6px;
  letter-spacing: 0.05em;
}

.identity-step-en {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.2em;
}

.identity-arrow {
  width: 36px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  margin-top: -30px;
}

.identity-arrow img {
  width: 100%;
}

.identity-closing {
  text-align: center;
  margin-bottom: 0;
  position: relative;
  z-index: 2;
}

.identity-closing .section-title {
  font-size: 38px;
  margin-bottom: 24px;
}

.identity-closing .section-subtitle {
  font-size: 14px;
}

/* ============================================
   SERVICE
   ============================================ */
.service {
  background: var(--gradient-purple);
  padding: 280px 24px 280px;
  position: relative;
  color: #fff;
  margin-top: -80px;
}

.service::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  right: 0;
  height: 220px;
  background: #fff;
  filter: drop-shadow(0 4px 6px rgba(0, 0, 0, 0.18)) drop-shadow(0 12px 20px rgba(0, 0, 0, 0.15));
  clip-path: polygon(
    0 0, 100% 0,
    100% 5%,
    97.5% 14.3%, 95% 23%, 92.5% 31.4%, 90% 39.2%, 87.5% 46.6%, 85% 53.5%, 82.5% 59.9%, 80% 65.8%, 77.5% 71.3%,
    75% 76.25%, 72.5% 80.8%, 70% 84.8%, 67.5% 88.4%, 65% 91.5%, 62.5% 94.1%, 60% 96.2%, 57.5% 97.9%, 55% 99.05%, 52.5% 99.8%,
    50% 100%,
    47.5% 99.9%, 45% 99.65%, 42.5% 99.2%, 40% 98.6%, 37.5% 97.8%, 35% 96.85%, 32.5% 95.7%, 30% 94.4%, 27.5% 92.9%,
    25% 91.25%, 22.5% 89.4%, 20% 87.4%, 17.5% 85.2%, 15% 82.85%, 12.5% 80.3%, 10% 77.6%, 7.5% 74.7%, 5% 71.65%, 2.5% 68.4%,
    0 65%
  );
}

.service::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 260px;
  background: #fff;
  clip-path: polygon(
    0 25%,
    5% 18.5%, 10% 13%, 15% 8.5%, 20% 5%, 25% 2.5%, 30% 1%, 35% 0.5%, 40% 1%, 45% 2.5%,
    50% 5%, 55% 8.5%, 60% 13%, 65% 18.5%, 70% 25%, 75% 32.5%, 80% 41%, 85% 50.5%, 90% 61%, 95% 72.5%,
    100% 85%,
    100% 100%,
    0 100%
  );
}

.service-inner {
  position: relative;
  z-index: 2;
  max-width: 1200px;
  margin: 0 auto;
}

.service .section-label {
  color: #fff;
}

.service .section-title {
  color: #fff;
}

.service .section-subtitle {
  color: rgba(255, 255, 255, 0.85);
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin: 70px auto 0;
  max-width: 1100px;
}

.service-card {
  background: #fff;
  border-radius: 8px;
  padding: 36px 32px 32px;
  display: flex;
  flex-direction: column;
  color: var(--color-text);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.service-card-title {
  font-family: "Roboto", var(--font-jp);
  font-size: 40px;
  font-weight: 900;
  text-align: center;
  line-height: 1.2;
  margin-bottom: 18px;
  letter-spacing: 0;
  padding-bottom: 0.1em;
  background: linear-gradient(95deg, #3D4E81 0%, #5753C9 50%, #6E7FF3 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  display: inline-block;
  width: 100%;
}

.service-card-sub {
  font-size: 19px;
  font-weight: 700;
  color: #475569;
  text-align: center;
  margin-bottom: 28px;
  letter-spacing: 0.02em;
}

.service-card-desc {
  font-size: 13px;
  color: var(--color-text);
  line-height: 1.95;
  margin-bottom: 24px;
}

.service-card-img {
  width: 100%;
  border-radius: 6px;
  overflow: hidden;
  margin-bottom: 22px;
  aspect-ratio: 295 / 320;
  background: #f0f0f0;
}

.service-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.service-card-label {
  background: #4a5568;
  color: #fff;
  text-align: center;
  padding: 13px;
  border-radius: 30px;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.1em;
  margin-bottom: 16px;
}

.service-card-result-sub {
  font-size: 12px;
  color: var(--color-text-muted);
  margin-bottom: 6px;
  line-height: 1.6;
  text-align: center;
}

.service-card-result {
  font-size: 26px;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.4;
  letter-spacing: 0.02em;
  text-align: center;
}

/* ============================================
   PRODUCTS
   ============================================ */
.products {
  padding: 100px 24px;
}

.products-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  max-width: 1100px;
  margin: 70px auto 0;
}

.product-card {
  text-align: center;
}

.product-name {
  font-size: 44px;
  font-weight: 900;
  color: var(--color-primary);
  letter-spacing: 0.02em;
  margin-bottom: 8px;
}

.product-name-jp {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-text-dark);
  letter-spacing: 0.3em;
  margin-bottom: 28px;
}

.products .section-label {
  font-size: 44px;
  font-weight: 900;
  -webkit-text-stroke: 1px currentColor;
}

.products {
  padding-top: 10px;
  margin-top: -100px;
}

.product-tagline {
  font-size: 26px;
  font-weight: 700;
  color: #475569;
  line-height: 1.7;
  margin-bottom: 36px;
}

.product-image {
  margin-bottom: 36px;
  border-radius: 8px;
  overflow: hidden;
}

.product-image img {
  width: 100%;
  height: auto;
  display: block;
}

.product-desc {
  font-size: 13px;
  color: var(--color-text);
  line-height: 2;
  text-align: left;
}

/* ============================================
   Client logos
   ============================================ */
.clients {
  padding: 60px 24px 80px;
  overflow: hidden;
}

.clients-track {
  display: flex;
  align-items: center;
  gap: 100px;
  width: max-content;
  animation: clients-slide 30s linear infinite;
}

@keyframes clients-slide {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

.clients-track:hover {
  animation-play-state: paused;
}

.client-logo {
  flex: 0 0 auto;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0.85;
  transition: opacity 0.3s;
}

.client-logo:hover {
  opacity: 1;
}

.client-logo img {
  max-height: 100%;
  width: auto;
  max-width: 160px;
  object-fit: contain;
}

/* ============================================
   COMPANY
   ============================================ */
.company {
  background: url('../img/company-bg.png') bottom / cover fixed no-repeat;
  padding: 100px 24px 120px;
  position: relative;
  overflow: hidden;
}

.company-inner {
  position: relative;
  z-index: 2;
  max-width: 900px;
  margin: 0 auto;
}

.company-table {
  margin-top: 60px;
  border-top: 1px solid #c2c6cd;
}

.company-row {
  display: grid;
  grid-template-columns: 200px 1fr;
  border-bottom: 1px solid #c2c6cd;
  padding: 28px 0;
  align-items: flex-start;
}

.company-row dt {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-text-dark);
  padding-left: 30px;
  letter-spacing: 0.1em;
}

.company-row dd {
  font-size: 14px;
  color: var(--color-text-dark);
  line-height: 2;
}

.executives {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.exec-row {
  display: flex;
  gap: 40px;
  font-size: 14px;
}

.exec-title {
  color: var(--color-text);
  min-width: 110px;
}

.exec-name {
  font-weight: 700;
  color: var(--color-text-dark);
}

.company .btn-contact-wrapper {
  margin-top: 70px;
}

/* ============================================
   Footer
   ============================================ */
.site-footer {
  background:
    url('../img/footer.png') center / cover scroll no-repeat,
    url('../img/company-bg.png') bottom / cover fixed no-repeat;
  background-blend-mode: multiply;
  color: #fff;
  padding: 36px 40px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1000px;
  margin: 0 auto;
}

.footer-logo img {
  height: 28px;
  filter: brightness(0) invert(1);
  opacity: 0.95;
}

.copyright {
  font-size: 12px;
  letter-spacing: 0.1em;
  opacity: 0.9;
}

/* ============================================
   Reveal animation
   ============================================ */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 48px;
  }
  .section-title {
    font-size: 34px;
  }
  .service-grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin-left: auto;
    margin-right: auto;
  }
  .products-grid {
    grid-template-columns: 1fr;
    gap: 80px;
  }
  .identity-steps {
    gap: 12px;
  }
  .identity-step {
    min-width: 110px;
  }
  .identity-step-icon {
    width: 70px;
    height: 70px;
  }
  .identity-arrow {
    width: 24px;
  }
}

@media (max-width: 768px) {
  .site-header {
    padding: 14px 16px;
  }
  .logo img {
    height: 26px;
  }
  .global-nav {
    gap: 12px;
  }
  .nav-link {
    display: none;
  }
  .nav-link:not(.active) {
    display: inline-block;
    font-size: 11px;
  }
  .btn-contact-header {
    padding: 10px 12px;
    font-size: 10px;
    gap: 8px;
  }
  .btn-contact-header .arrow-circle {
    width: 20px;
    height: 20px;
  }
  .hero {
    padding: 110px 20px 60px;
  }
  .hero-inner {
    grid-template-columns: 1fr;
  }
  .hero-content {
    padding-left: 0;
    text-align: left;
  }
  .hero-title {
    font-size: 36px;
  }
  .hero-image {
    order: -1;
    margin-bottom: 16px;
  }
  .hero-image img {
    max-width: 80%;
  }
  .section {
    padding: 70px 20px;
  }
  .section-label {
    font-size: 22px;
  }
  .section-title {
    font-size: 26px;
  }
  .identity-steps {
    flex-direction: column;
    gap: 24px;
    margin: 60px 0;
  }
  .identity-arrow {
    transform: rotate(90deg);
    margin: 0;
    width: 20px;
  }
  .identity-step {
    min-width: auto;
  }
  .service {
    padding: 100px 20px 120px;
  }
  .service::before,
  .service::after {
    height: 60px;
  }
  .products-grid {
    margin-top: 50px;
  }
  .product-name {
    font-size: 34px;
  }
  .company-row {
    grid-template-columns: 110px 1fr;
    padding: 20px 0;
  }
  .company-row dt {
    padding-left: 0;
    font-size: 13px;
  }
  .company-row dd {
    font-size: 13px;
  }
  .exec-row {
    flex-direction: column;
    gap: 2px;
  }
  .footer-inner {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
  .site-footer {
    padding-right: 24px;
    padding-left: 24px;
  }
  .clients-track {
    gap: 24px;
  }
  .client-logo {
    height: 36px;
  }
  .client-logo img {
    max-width: 120px;
  }
}

@media (max-width: 360px) {
  .logo img {
    height: 22px;
  }
  .global-nav {
    gap: 8px;
  }
  .nav-link:not(.active) {
    font-size: 9px;
  }
  .btn-contact-header {
    padding: 8px 9px;
    font-size: 9px;
    gap: 6px;
  }
  .btn-contact-header .arrow-circle {
    width: 18px;
    height: 18px;
  }
}