/* ============================================================
   1. CSS Variables
   ============================================================ */
:root {
  /* Colors - Ocean Blue palette */
  --color-primary:        #003c5e;
  --color-primary-deep:   #001f33;
  --color-primary-darker: #00121f;
  --color-accent:         #00a3c4;
  --color-accent-light:   #4ec3dc;
  --color-bg:             #ffffff;
  --color-bg-alt:         #f4f7fa;
  --color-bg-dark:        #001220;
  --color-text:           #0a1929;
  --color-text-muted:     #54616e;
  --color-text-on-dark:   #d9e3ec;
  --color-border:         #e3e8ee;
  --color-border-on-dark: rgba(255, 255, 255, 0.12);

  /* Typography */
  --font-serif: "Cormorant Garamond", "Noto Serif JP", "Times New Roman", serif;
  --font-sans:  "Inter", "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
  --font-jp:    "Noto Sans JP", -apple-system, BlinkMacSystemFont, sans-serif;

  /* Layout */
  --container-max: 1200px;
  --container-pad: clamp(20px, 5vw, 40px);
  --section-pad-y: clamp(96px, 12vw, 160px);

  /* Easing & Duration */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --dur-base: 800ms;
  --dur-fast: 400ms;
}

/* ============================================================
   2. Base
   ============================================================ */
html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-text);
  background-color: var(--color-bg);
  overflow-x: hidden;
}

a {
  color: inherit;
  transition: color var(--dur-fast) var(--ease-out), opacity var(--dur-fast) var(--ease-out);
}

a:hover {
  color: var(--color-accent);
}

/* Selection */
::selection {
  background: var(--color-accent);
  color: #fff;
}

/* ============================================================
   3. Layout utilities
   ============================================================ */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

.section {
  position: relative;
  padding-block: var(--section-pad-y);
}

.section--service,
.section--company {
  background-color: var(--color-bg-alt);
}

.section__header {
  margin-bottom: clamp(56px, 8vw, 96px);
}

.section__num {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--color-accent);
  display: inline-block;
  margin-bottom: 12px;
}

.section__eyebrow {
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.32em;
  color: var(--color-text-muted);
  margin-bottom: 24px;
  text-transform: uppercase;
}

.section__title {
  font-size: clamp(40px, 6.4vw, 76px);
  line-height: 1.1;
  letter-spacing: -0.01em;
  font-weight: 500;
  color: var(--color-text);
}

.section__title--serif {
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 500;
}

/* ============================================================
   4. Header / Nav
   ============================================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  transition: background-color var(--dur-fast) var(--ease-out),
              box-shadow var(--dur-fast) var(--ease-out),
              backdrop-filter var(--dur-fast) var(--ease-out);
}

.site-header.is-scrolled {
  background-color: rgba(255, 255, 255, 0.78);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  box-shadow: 0 1px 0 rgba(10, 25, 41, 0.06);
}

/* Hero覆い被さり中はテキストを白に */
.site-header:not(.is-scrolled) .site-header__logo-mark,
.site-header:not(.is-scrolled) .site-header__logo-jp,
.site-header:not(.is-scrolled) .site-nav__link {
  color: rgba(255, 255, 255, 0.92);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  gap: 24px;
}

.site-header__logo {
  display: flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1;
}

.site-header__logo-mark {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 20px;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--color-text);
  transition: color var(--dur-fast) var(--ease-out);
}

.site-header__logo-jp {
  font-family: var(--font-jp);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--color-text-muted);
  transition: color var(--dur-fast) var(--ease-out);
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(16px, 3.2vw, 40px);
}

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--color-text);
  position: relative;
  padding-block: 4px;
  transition: color var(--dur-fast) var(--ease-out);
}

.site-nav__num {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 11px;
  color: var(--color-accent);
  letter-spacing: 0.04em;
}

.site-nav__label {
  position: relative;
}

.site-nav__label::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -4px;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: right center;
  transition: transform 400ms var(--ease-out);
}

.site-nav__link:hover .site-nav__label::after {
  transform: scaleX(1);
  transform-origin: left center;
}

@media (max-width: 768px) {
  .site-header__inner { height: 60px; }
  .site-header__logo-mark { font-size: 16px; }
  .site-header__logo-jp { display: none; }
  .site-nav__list { gap: 14px; }
  .site-nav__link { font-size: 10px; letter-spacing: 0.12em; }
  .site-nav__num { display: none; }
}

@media (max-width: 380px) {
  .site-header__inner { height: 56px; }
  .site-header__logo-mark { font-size: 14px; }
  .site-nav__list { gap: 10px; }
  .site-nav__link { font-size: 9px; }
}

/* ============================================================
   5. Hero
   ============================================================ */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  align-items: center;
  overflow: hidden;
  color: #fff;
  isolation: isolate;
}

.hero__bg {
  position: absolute;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  background-color: var(--color-primary-darker);
}

.hero__bg-gradient {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 70% at 20% 20%, rgba(0, 163, 196, 0.32), transparent 60%),
    radial-gradient(ellipse 60% 60% at 80% 80%, rgba(0, 60, 94, 0.55), transparent 60%),
    linear-gradient(180deg, #001220 0%, #001f33 40%, #00263f 100%);
  will-change: transform;
}

.hero__bg-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.55;
  mix-blend-mode: screen;
  will-change: transform;
}

.hero__bg-glow--a {
  width: 60vw;
  height: 60vw;
  top: -10%;
  left: -10%;
  background: radial-gradient(circle, #0090b3 0%, transparent 70%);
  animation: heroGlowA 18s ease-in-out infinite alternate;
}

.hero__bg-glow--b {
  width: 50vw;
  height: 50vw;
  bottom: -20%;
  right: -10%;
  background: radial-gradient(circle, #003c5e 0%, transparent 70%);
  animation: heroGlowB 22s ease-in-out infinite alternate;
}

@keyframes heroGlowA {
  0%   { transform: translate(0, 0) scale(1); }
  100% { transform: translate(80px, 60px) scale(1.15); }
}

@keyframes heroGlowB {
  0%   { transform: translate(0, 0) scale(1); }
  100% { transform: translate(-60px, -40px) scale(1.1); }
}

.hero__bg-noise {
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(0deg, rgba(255,255,255,0.012) 0 1px, transparent 1px 3px),
    repeating-linear-gradient(90deg, rgba(255,255,255,0.012) 0 1px, transparent 1px 3px);
  pointer-events: none;
  opacity: 0.6;
}

.hero__inner {
  position: relative;
  width: 100%;
  padding-top: 120px;
  padding-bottom: 80px;
  z-index: 1;
}

.hero__eyebrow {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--color-accent-light);
  margin-bottom: 28px;
  opacity: 0;
  transform: translateY(16px);
}

.hero__title {
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 500;
  font-size: clamp(56px, 11vw, 156px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  margin-bottom: 32px;
}

.hero__title-line {
  display: block;
  opacity: 0;
  transform: translateY(28px);
}

.hero__title-line--accent {
  color: transparent;
  background: linear-gradient(120deg, #ffffff 0%, #4ec3dc 60%, #00a3c4 100%);
  -webkit-background-clip: text;
  background-clip: text;
}

.hero__subtitle {
  font-family: var(--font-jp);
  font-size: clamp(15px, 1.6vw, 19px);
  font-weight: 400;
  letter-spacing: 0.08em;
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.88);
  max-width: 540px;
  opacity: 0;
  transform: translateY(16px);
}

.hero__scroll {
  position: absolute;
  left: var(--container-pad);
  bottom: 32px;
  display: inline-flex;
  align-items: center;
  gap: 16px;
  font-size: 11px;
  letter-spacing: 0.32em;
  color: rgba(255, 255, 255, 0.72);
  opacity: 0;
  transform: translateY(8px);
}

.hero__scroll-text {
  font-weight: 500;
}

.hero__scroll-line {
  position: relative;
  display: block;
  width: 80px;
  height: 1px;
  background: rgba(255, 255, 255, 0.24);
  overflow: hidden;
}

.hero__scroll-line::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 30%;
  height: 100%;
  background: var(--color-accent-light);
  animation: scrollLine 2.4s var(--ease-in-out) infinite;
}

@keyframes scrollLine {
  0%   { transform: translateX(-100%); }
  100% { transform: translateX(330%); }
}

.hero__index {
  position: absolute;
  right: var(--container-pad);
  bottom: 32px;
  font-family: var(--font-serif);
  font-style: italic;
  text-align: right;
  line-height: 1.4;
  color: rgba(255, 255, 255, 0.6);
  opacity: 0;
  transform: translateY(8px);
}

.hero__index-num {
  display: block;
  font-size: 36px;
  letter-spacing: 0.04em;
  color: rgba(255, 255, 255, 0.85);
}

.hero__index-label {
  display: block;
  font-family: var(--font-sans);
  font-style: normal;
  font-size: 10px;
  letter-spacing: 0.32em;
  margin-top: 4px;
}

/* JS有効時のみヒーロー要素を初期非表示にする（noscript / SEO配慮） */
.js .hero__eyebrow,
.js .hero__title-line,
.js .hero__subtitle,
.js .hero__scroll,
.js .hero__index {
  opacity: 0;
  transform: translateY(16px);
}

.js .hero__title-line { transform: translateY(28px); }

/* Hero entry animation (triggered by .is-loaded on body) */
.js .is-loaded .hero__eyebrow,
.js .is-loaded .hero__title-line,
.js .is-loaded .hero__subtitle,
.js .is-loaded .hero__scroll,
.js .is-loaded .hero__index {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 1100ms var(--ease-out), transform 1100ms var(--ease-out);
}

.js .is-loaded .hero__eyebrow            { transition-delay: 200ms; }
.js .is-loaded .hero__title-line:nth-child(1) { transition-delay: 360ms; }
.js .is-loaded .hero__title-line:nth-child(2) { transition-delay: 520ms; }
.js .is-loaded .hero__subtitle           { transition-delay: 760ms; }
.js .is-loaded .hero__scroll             { transition-delay: 1000ms; }
.js .is-loaded .hero__index              { transition-delay: 1100ms; }

@media (max-width: 768px) {
  .hero__inner { padding-top: 96px; padding-bottom: 96px; }
  .hero__index { display: none; }
  .hero__scroll { left: var(--container-pad); }
}

/* ============================================================
   6. About
   ============================================================ */
.about__body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  max-width: 920px;
}

.about__lead {
  font-family: var(--font-jp);
  font-size: clamp(20px, 2.4vw, 28px);
  font-weight: 500;
  line-height: 1.9;
  letter-spacing: 0.04em;
  color: var(--color-text);
}

.about__lead strong {
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 500;
  color: var(--color-primary);
}

.about__text {
  font-size: 15px;
  line-height: 2.1;
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

@media (max-width: 768px) {
  .about__lead br { display: none; }
  .about__text br { display: none; }
}

/* ============================================================
   7. Service
   ============================================================ */
.service__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background-color: var(--color-border);
  border: 1px solid var(--color-border);
}

.service-card {
  position: relative;
  background-color: var(--color-bg);
  padding: 56px 40px 64px;
  transition: background-color 600ms var(--ease-out);
}

.service-card:hover {
  background-color: #ffffff;
}

.service-card__num {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 14px;
  color: var(--color-accent);
  margin-bottom: 32px;
  letter-spacing: 0.04em;
}

.service-card__title {
  margin-bottom: 24px;
}

.service-card__title-en {
  display: block;
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 500;
  font-size: clamp(28px, 3.2vw, 36px);
  line-height: 1.2;
  color: var(--color-primary);
  margin-bottom: 6px;
}

.service-card__title-jp {
  display: block;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--color-text-muted);
}

.service-card__text {
  font-size: 14px;
  line-height: 2;
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

.service-card::before {
  content: "";
  position: absolute;
  left: 40px;
  bottom: 0;
  width: 40px;
  height: 1px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 600ms var(--ease-out);
}

.service-card:hover::before {
  transform: scaleX(1);
}

@media (max-width: 1024px) {
  .service__grid { grid-template-columns: 1fr; }
  .service-card { padding: 40px 28px 48px; }
}

/* ============================================================
   8. Message
   ============================================================ */
.message__body {
  display: grid;
  grid-template-columns: minmax(240px, 380px) 1fr;
  gap: clamp(40px, 6vw, 88px);
  align-items: start;
}

.message__portrait {
  position: relative;
}

.message__portrait-frame {
  position: relative;
  aspect-ratio: 4 / 5;
  background: var(--color-bg-alt);
  overflow: hidden;
  border: 1px solid var(--color-border);
}

.message__portrait-img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.message__lead {
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 500;
  font-size: clamp(28px, 3.6vw, 44px);
  line-height: 1.4;
  letter-spacing: 0.02em;
  color: var(--color-primary);
  margin-bottom: 32px;
}

.message__text {
  font-size: 15px;
  line-height: 2.1;
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

.message__text p + p {
  margin-top: 20px;
}

.message__sign {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text);
}

.message__sign-role {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--color-text-muted);
}

.message__sign-name {
  font-family: var(--font-jp);
  font-size: 18px;
  font-weight: 500;
  letter-spacing: 0.08em;
}

@media (max-width: 768px) {
  .message__body { grid-template-columns: 1fr; }
  .message__portrait-frame { max-width: none; }
  .message__lead br { display: none; }
  .message__text br { display: none; }
}

/* ============================================================
   9. Company
   ============================================================ */
.company__list {
  border-top: 1px solid var(--color-border);
  max-width: 880px;
}

.company__row {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 24px;
  padding: 28px 0;
  border-bottom: 1px solid var(--color-border);
}

.company__row dt {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.24em;
  color: var(--color-accent);
  text-transform: uppercase;
  padding-top: 4px;
}

.company__row dd {
  font-family: var(--font-jp);
  font-size: 15px;
  line-height: 1.9;
  color: var(--color-text);
  letter-spacing: 0.04em;
}

@media (max-width: 768px) {
  .company__row {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 20px 0;
  }
  .company__row dt { font-size: 11px; }
}

/* ============================================================
   10. Footer
   ============================================================ */
.site-footer {
  background-color: var(--color-bg-dark);
  color: var(--color-text-on-dark);
  padding-block: clamp(48px, 6vw, 72px);
}

.site-footer__inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: start;
}

.site-footer__logo {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 28px;
  letter-spacing: 0.04em;
  color: #fff;
  margin-bottom: 12px;
}

.site-footer__address {
  font-family: var(--font-jp);
  font-size: 13px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.6);
}

.site-footer__nav ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
  align-items: flex-end;
}

.site-footer__nav a {
  font-size: 12px;
  letter-spacing: 0.24em;
  color: rgba(255, 255, 255, 0.78);
}

.site-footer__nav a:hover {
  color: var(--color-accent-light);
}

.site-footer__copy {
  grid-column: 1 / -1;
  margin-top: 56px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border-on-dark);
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.5);
}

@media (max-width: 640px) {
  .site-footer__inner {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .site-footer__nav ul { align-items: flex-start; }
}

/* ============================================================
   11. Animations - data-animate（JS有効時のみ初期非表示）
   ============================================================ */
.js [data-animate] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 900ms var(--ease-out), transform 900ms var(--ease-out);
  will-change: opacity, transform;
}

.js [data-animate].is-visible {
  opacity: 1;
  transform: translateY(0);
}

.js .service-card[data-animate]:nth-of-type(1) { transition-delay: 0ms; }
.js .service-card[data-animate]:nth-of-type(2) { transition-delay: 120ms; }
.js .service-card[data-animate]:nth-of-type(3) { transition-delay: 240ms; }

@media (prefers-reduced-motion: reduce) {
  .js [data-animate],
  .js .hero__eyebrow,
  .js .hero__title-line,
  .js .hero__subtitle,
  .js .hero__scroll,
  .js .hero__index {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
}