:root {
  /* Colors */
  --color-bg: #ffffff;
  --color-surface: #f5f5f5;
  --color-text: #222222;
  --color-text-light: #666666;
  --color-border: #e6e6e6;
  --color-accent: #915c8b;
  /* 二藍色 Futaai */
  --color-accent-hover: #7b4c75;

  /* Fonts */
  --font-ja: 'Noto Sans JP', sans-serif;
  --font-en: 'Montserrat', sans-serif;

  /* Layout */
  --max-width: 1200px;
  --header-height: 70px;
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-ja);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition);
}

ul {
  list-style: none;
}

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

.section-title {
  font-family: var(--font-en);
  font-size: 2.5rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 3rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text);
  position: relative;
}

.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  background-color: var(--color-accent);
  margin: 15px auto 0;
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  z-index: 100;
  transition: var(--transition);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 100%;
  padding: 0 20px;
  max-width: var(--max-width);
  margin: 0 auto;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--color-text);
}

.nav ul {
  display: flex;
  gap: 30px;
}

.nav a {
  font-family: var(--font-en);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

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

.hamburger {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 30px;
  height: 20px;
  cursor: pointer;
}

.hamburger span {
  display: block;
  height: 2px;
  width: 100%;
  background-color: var(--color-text);
  transition: var(--transition);
}

/* Hero Section */
.hero {
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  background-color: var(--color-surface);
  overflow: hidden;
}

.hero-slider {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
}

.hero-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  opacity: 0;
  animation: fadeSlider 15s infinite;
}

.hero-slide:nth-child(1) {
  background-image: linear-gradient(rgba(245, 245, 245, 0.6), rgba(245, 245, 245, 0.8)), url('../背景用画像/hero_bg_1_1771847405866.png');
  animation-delay: 0s;
}

.hero-slide:nth-child(2) {
  background-image: linear-gradient(rgba(245, 245, 245, 0.6), rgba(245, 245, 245, 0.8)), url('../背景用画像/hero_bg_2_1771847428492.png');
  animation-delay: 5s;
}

.hero-slide:nth-child(3) {
  background-image: linear-gradient(rgba(245, 245, 245, 0.6), rgba(245, 245, 245, 0.8)), url('../背景用画像/hero_bg_3_1771847449572.png');
  animation-delay: 10s;
}

@keyframes fadeSlider {
  0% {
    opacity: 0;
  }

  10% {
    opacity: 1;
  }

  33% {
    opacity: 1;
  }

  43% {
    opacity: 0;
  }

  100% {
    opacity: 0;
  }
}

.hero-content {
  text-align: center;
  position: relative;
  z-index: 1;
  opacity: 0;
  transform: translateY(30px);
  animation: fadeUp 1s forwards 0.5s;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: 0.1em;
}

.hero-subtitle {
  font-family: var(--font-en);
  font-size: 1.2rem;
  color: var(--color-text-light);
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

@keyframes fadeUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Gallery Section */
.gallery-section {
  padding: 100px 0;
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 30px;
}

.gallery-item {
  position: relative;
  overflow: hidden;
  border-radius: 8px;
  background-color: var(--color-surface);
  aspect-ratio: 1;
  cursor: pointer;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
  transition: var(--transition);
}

.gallery-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.gallery-item:hover img {
  transform: scale(1.08);
}

.gallery-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  padding: 20px;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
  color: white;
  opacity: 0;
  transform: translateY(20px);
  transition: var(--transition);
}

.gallery-item:hover .gallery-overlay {
  opacity: 1;
  transform: translateY(0);
}


/* Links Section */
.links-section {
  padding: 100px 0;
  background-color: var(--color-surface);
}

.links-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  max-width: 900px;
  margin: 0 auto;
}

.link-card {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 15px;
  padding: 20px;
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  color: var(--color-text);
  font-weight: 600;
  transition: var(--transition);
}

.link-card:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  box-shadow: 0 5px 15px rgba(145, 92, 139, 0.1);
  /* Subtle shadow tinted with Futaai */
  transform: translateY(-3px);
}

.link-icon {
  font-size: 1.5rem;
}

/* Footer */
.footer {
  padding: 40px 20px;
  text-align: center;
  background-color: var(--color-bg);
  color: var(--color-text-light);
  border-top: 1px solid var(--color-border);
  font-family: var(--font-en);
  font-size: 0.85rem;
}

/* Lightbox Modal */
.lightbox {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(25, 25, 25, 0.95);
  z-index: 1000;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}

.lightbox.active {
  opacity: 1;
  visibility: visible;
}

.lightbox-content {
  position: relative;
  max-width: 90%;
  max-height: 85vh;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.lightbox-img {
  max-width: 100%;
  max-height: 80vh;
  object-fit: contain;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
  border-radius: 4px;
}


.lightbox-close {
  position: absolute;
  top: 20px;
  right: 30px;
  color: white;
  font-size: 2.5rem;
  font-weight: 300;
  cursor: pointer;
  transition: color 0.2s;
  z-index: 1001;
}

.lightbox-close:hover {
  color: var(--color-accent);
}

/* Responsive */
@media (max-width: 768px) {
  .hero {
    height: auto;
    aspect-ratio: 4 / 4;
    /* 正方形かそれに近いアスペクト比で表示 */
    min-height: 50vh;
  }

  /* Adjust background for mobile */
  .hero-slide {
    background-attachment: scroll;
  }

  .hero-title {
    font-size: 2.5rem;
  }

  .gallery-grid {
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 15px;
  }

  .hamburger {
    display: flex;
    z-index: 101;
  }

  .nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 250px;
    height: 100vh;
    background-color: var(--color-bg);
    box-shadow: -5px 0 20px rgba(0, 0, 0, 0.05);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
  }

  .nav.active {
    right: 0;
  }

  .nav ul {
    flex-direction: column;
    text-align: center;
  }

  .hamburger.active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
  }

  .hamburger.active span:nth-child(2) {
    opacity: 0;
  }

  .hamburger.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
  }
}