:root {
  /* Colors */
  --color-navy: #151e2d;
  /* Professional Deep Navy */
  --color-charcoal: #333333;
  --color-text: #1a1a1a;
  --color-text-light: #717171;
  --color-white: #ffffff;
  --color-bg-light: #f9f9f9;
  --color-border: #e0e0e0;

  /* Typography */
  --font-serif: "YuMincho", "Yu Mincho", "Hiragino Mincho ProN", "HGS明朝E", serif;
  --font-sans: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;

  /* Spacing */
  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 32px;
  --spacing-lg: 64px;
  --spacing-xl: 120px;

  /* Container */
  --container-width: 1200px;
}

/* Reset & Base */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background-color: var(--color-white);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-serif);
  font-weight: 500;
  line-height: 1.4;
  letter-spacing: 0.05em;
}

a {
  color: inherit;
  text-decoration: none;
  transition: opacity 0.3s ease;
}

a:hover {
  opacity: 0.7;
}

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

li {
  list-style: none;
}

/* Utilities */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
}

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

.text-serif {
  font-family: var(--font-serif);
}

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

/* Button - Minimal & Professional */
.btn {
  display: inline-block;
  padding: 12px 32px;
  font-size: 14px;
  letter-spacing: 0.1em;
  border: 1.5px solid var(--color-navy);
  color: var(--color-navy);
  background: transparent;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-align: center;
}

.btn:hover {
  background: var(--color-navy);
  color: var(--color-white);
}

.btn-primary {
  background: var(--color-navy);
  color: var(--color-white);
  border-color: var(--color-navy);
}

.btn-primary:hover {
  background: transparent;
  color: var(--color-navy);
}

/* Specific for LINE/CTA on dark backgrounds */
.btn-light {
  background: var(--color-white);
  color: var(--color-navy);
  border-color: var(--color-white);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.1);
}

.btn-light:hover {
  background: #f0f0f0;
  border-color: #f0f0f0;
  color: var(--color-navy);
  transform: translateY(-2px);
}

/* Header */
.header {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  padding: 30px 0;
  z-index: 100;
}

.header__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.header__logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: 0.1em;
}

.header__nav {
  display: flex;
  gap: 30px;
  align-items: center;
}

.header__nav a:not(.btn) {
  font-size: 14px;
  letter-spacing: 0.05em;
  font-weight: 500;
  color: var(--color-white);
}

.header .btn {
  border-color: var(--color-white);
  color: var(--color-white);
  border-width: 1px;
  padding: 10px 24px;
  background: transparent;
}

.header .btn:hover {
  background: var(--color-white);
  color: var(--color-navy);
  transform: translateY(-1px);
}

/* First View (FV) */
.fv {
  position: relative;
  height: 90vh;
  min-height: 600px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background-color: var(--color-bg-light);
  /* Fallback */
}

/* Atmospheric Background - Placeholder Styling */
.fv__bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, #1e2a38 0%, #0f172a 100%);
  /* Premium Navy Gradient */
  opacity: 0.9;
  z-index: 1;
}

.fv__content {
  position: relative;
  z-index: 2;
  padding-left: 5%;
}

.fv__title {
  font-size: 4rem;
  line-height: 1.3;
  margin-bottom: 30px;
  color: var(--color-white);
  /* Changed to white */
  letter-spacing: 0.05em;
}

.fv__subtitle {
  font-size: 1.1rem;
  line-height: 2;
  margin-bottom: 50px;
  color: rgba(255, 255, 255, 0.8);
  /* Changed to light gray */
  font-weight: 400;
}

.btn-lg {
  padding: 18px 60px;
  font-size: 16px;
}

.btn-sub {
  display: block;
  font-size: 12px;
  margin-top: 4px;
  opacity: 0.8;
  font-weight: normal;
}

/* Section Common */
.section-title {
  font-size: 2.2rem;
  margin-bottom: 1.5rem;
  color: var(--color-navy);
}

.section-desc {
  max-width: 800px;
  margin: 0 auto;
  font-size: 1.1rem;
  line-height: 2;
}

/* Brand Philosophy */
.philosophy {
  background-color: var(--color-white);
  padding: 100px 0 120px;
  text-align: center;
}

.philosophy__title {
  font-size: 1.2rem;
  margin-bottom: 60px;
  color: var(--color-text-light);
  /* Subtle labeling */
  font-weight: normal;
  letter-spacing: 0.1em;
}

.philosophy__content {
  font-size: 1.15rem;
  line-height: 2.4;
  color: var(--color-navy);
}

.philosophy__content p {
  margin-bottom: 40px;
}

.philosophy__content p:last-child {
  margin-bottom: 0;
}

.philosophy__highlight {
  font-size: 1.3rem;
  font-weight: 500;
  margin-top: 60px;
}

/* Concept */
.concept__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  margin-top: 80px;
}

.concept__item-title {
  font-size: 1.4rem;
  margin-bottom: 20px;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 15px;
  color: var(--color-navy);
}

/* Stance */
.stance {
  background-color: var(--color-bg-light);
}

.stance .section-header {
  margin-bottom: 60px;
}

/* Area */
.area__desc {
  margin-bottom: 50px;
}

.area__map {
  width: 100%;
  height: 400px;
  background-color: #f0f0f0;
  /* Placeholder */
  display: flex;
  align-items: center;
  justify-content: center;
  color: #999;
}

/* CTA Section */
.cta-section {
  background-color: #fafafa;
  padding: 100px 0;
}

.cta__title {
  font-size: 2.5rem;
  margin-bottom: 20px;
}

.cta__text {
  margin-bottom: 50px;
  font-size: 1.1rem;
}

/* Footer */
.footer {
  background-color: var(--color-navy);
  color: white;
  padding: 60px 0 30px;
  text-align: center;
}

.copyright {
  opacity: 0.6;
  font-size: 0.8rem;
  letter-spacing: 0.1em;
}

.footer__note {
  margin-top: 20px;
  font-size: 0.75rem;
  opacity: 0.8;
  letter-spacing: 0.05em;
}

/* Mobile Bar */
.mobile-bar {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  background-color: rgba(28, 42, 57, 0.95);
  /* Semi-transparent Navy */
  padding: 15px;
  z-index: 1000;
  backdrop-filter: blur(5px);
}

.mobile-bar__btn {
  display: block;
  width: 100%;
  text-align: center;
  color: white;
  font-weight: bold;
  padding: 12px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 4px;
}

/* Responsive Adjustments */
@media (max-width: 768px) {
  :root {
    --spacing-xl: 60px;
  }

  .header {
    padding: 20px 0;
  }

  .header__nav {
    display: none;
  }

  /* Simplify for mobile for now */

  .fv__title {
    font-size: 2.5rem;
  }

  .fv__bg {
    background: linear-gradient(135deg, #eef2f3 0%, #8e9eab 100%);
  }

  .concept__grid,
  .service__grid {
    grid-template-columns: 1fr;
  }

  .stance__inner {
    flex-direction: column;
    gap: 30px;
    align-items: flex-start;
  }

  .stance__inner .section-title {
    font-size: 2rem;
  }

  .mobile-bar {
    display: block;
  }

  .footer {
    padding-bottom: 100px;
  }

  /* Space for mobile bar */
}