@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+JP:wght@300;600;900&family=Shippori+Mincho:wght@400;700;800&family=Montserrat:wght@300;400;600&display=swap');

:root {
  --color-bg: #060606;
  --color-gold-light: #f3e5ab;
  --color-gold: #c5a059;
  --color-gold-dark: #8e6f3e;
  --color-gold-glow: rgba(197, 160, 89, 0.4);
  --color-text-main: #f0f0f0;
  --color-text-muted: #8a8a8a;
  --font-japanese: 'Shippori Mincho', 'Noto Serif JP', serif;
  --font-english: 'Montserrat', sans-serif;
  --transition-smooth: all 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Base Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  user-select: none;
}

html, body {
  background-color: var(--color-bg);
  color: var(--color-text-main);
  font-family: var(--font-japanese);
  overflow-x: hidden;
  min-height: 100vh;
  width: 100%;
}

/* Custom WebGL Canvas */
#webgl-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 1;
  pointer-events: auto;
}

/* Scroll Container */
.scroll-container {
  position: relative;
  width: 100%;
  z-index: 2;
  pointer-events: none; /* Let pointer events pass to WebGL canvas, except on interactive elements */
}

/* Sections */
section {
  position: relative;
  width: 100%;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 6rem 10%;
  box-sizing: border-box;
}

/* Enable pointer events on section content */
.section-content {
  pointer-events: auto;
  position: relative;
  width: 100%;
  max-width: 1200px;
}

/* Loading Overlay */
#loader {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: #030303;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  transition: opacity 1.5s cubic-bezier(0.77, 0, 0.175, 1), visibility 1.5s;
}

#loader.loaded {
  opacity: 0;
  visibility: hidden;
}

.loader-logo {
  font-size: 2.2rem;
  font-weight: 600;
  letter-spacing: 0.3rem;
  color: var(--color-gold);
  text-shadow: 0 0 15px var(--color-gold-glow);
  margin-bottom: 2rem;
  font-family: var(--font-english);
  opacity: 0;
  transform: translateY(20px);
  animation: fadeInVertical 1.5s forwards 0.5s;
}

.loader-bar-container {
  width: 200px;
  height: 1px;
  background: rgba(255, 255, 255, 0.1);
  position: relative;
  overflow: hidden;
}

.loader-bar {
  width: 0%;
  height: 100%;
  background: var(--color-gold);
  box-shadow: 0 0 8px var(--color-gold);
  transition: width 0.4s ease-out;
}

.loader-percentage {
  margin-top: 0.8rem;
  font-family: var(--font-english);
  font-size: 0.8rem;
  letter-spacing: 0.2rem;
  color: var(--color-gold);
}

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

/* Custom Cursor */
.custom-cursor {
  width: 10px;
  height: 10px;
  background: var(--color-gold);
  border-radius: 50%;
  position: fixed;
  top: 0;
  left: 0;
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 10000;
  mix-blend-mode: difference;
  transition: width 0.2s, height 0.2s, background-color 0.2s;
}

.custom-cursor-follower {
  width: 30px;
  height: 30px;
  border: 1px solid var(--color-gold);
  border-radius: 50%;
  position: fixed;
  top: 0;
  left: 0;
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 9999;
  transition: transform 0.08s ease-out, width 0.3s, height 0.3s, border-color 0.3s;
}

body:hover .custom-cursor,
body:hover .custom-cursor-follower {
  opacity: 1;
}

.cursor-hover {
  width: 40px;
  height: 40px;
  background-color: transparent;
}

.cursor-follower-hover {
  width: 50px;
  height: 50px;
  border-color: var(--color-gold-light);
  background-color: rgba(197, 160, 89, 0.15);
  box-shadow: 0 0 15px var(--color-gold-glow);
}

/* Header & Navigation */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 2.5rem 6rem; /* 縦横の余白を少し広げました */
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 100;
  pointer-events: none;
}

.logo {
  pointer-events: auto;
  font-size: 1.4rem; /* アルファベット表示用に少し縮小 */
  font-weight: 600;
  letter-spacing: 0.15rem; /* 字間を欧文向けに調整 */
  color: var(--color-gold);
  text-decoration: none;
  font-family: var(--font-english); /* Montserratに変更 */
  text-shadow: 0 2px 4px rgba(0,0,0,0.5);
  transition: var(--transition-smooth);
  margin-left: 3rem; /* さらに右側に寄せるための余白を追加 */
}

.logo:hover {
  color: var(--color-gold-light);
  text-shadow: 0 0 10px var(--color-gold-glow);
}

.audio-control {
  pointer-events: auto;
  background: rgba(15, 15, 15, 0.6);
  border: 1px solid rgba(197, 160, 89, 0.3);
  padding: 0.8rem 1.2rem;
  border-radius: 30px;
  color: var(--color-gold);
  font-family: var(--font-english);
  font-size: 0.75rem;
  letter-spacing: 0.15rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
  transition: var(--transition-smooth);
}

.audio-control:hover {
  background: rgba(197, 160, 89, 0.15);
  border-color: var(--color-gold);
  box-shadow: 0 0 15px var(--color-gold-glow);
  color: var(--color-gold-light);
}

.audio-control svg {
  width: 14px;
  height: 14px;
  fill: currentColor;
}

/* Side Navigation / Indicator */
.side-nav {
  position: fixed;
  right: 3rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.side-nav-item {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 1rem;
  text-decoration: none;
  color: var(--color-text-muted);
  font-family: var(--font-japanese);
  font-size: 0.85rem;
  letter-spacing: 0.1rem;
  transition: var(--transition-smooth);
  pointer-events: auto;
  cursor: pointer;
}

.side-nav-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
  border: 1px solid transparent;
  transition: var(--transition-smooth);
}

.side-nav-label {
  opacity: 0;
  transform: translateX(10px);
  transition: var(--transition-smooth);
}

.side-nav-item:hover .side-nav-label {
  opacity: 1;
  transform: translateX(0);
  color: var(--color-gold-light);
}

.side-nav-item:hover .side-nav-dot {
  background: var(--color-gold);
  box-shadow: 0 0 8px var(--color-gold);
  transform: scale(1.3);
}

.side-nav-item.active .side-nav-dot {
  background: var(--color-gold);
  border-color: var(--color-gold-light);
  box-shadow: 0 0 10px var(--color-gold);
  transform: scale(1.5);
}

.side-nav-item.active .side-nav-label {
  opacity: 1;
  transform: translateX(0);
  color: var(--color-gold);
  font-weight: 700;
}

/* Section Typographies and Content Layout */
.scrolling-title-wrap {
  writing-mode: vertical-rl;
  text-orientation: upright;
  position: absolute;
  left: 2%;
  top: 15%;
  height: 70%;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.vertical-title {
  font-size: 3.5rem;
  font-weight: 800;
  letter-spacing: 0.8rem;
  color: var(--color-text-main);
  text-shadow: 0 4px 10px rgba(0,0,0,0.8);
  font-family: var(--font-japanese);
  line-height: 1.5;
}

.vertical-title span {
  color: var(--color-gold);
}

.subtitle-horizontal {
  position: absolute;
  bottom: 10%;
  left: 10%;
  max-width: 450px;
  line-height: 2;
  font-size: 1.05rem;
  color: var(--color-text-muted);
  text-shadow: 0 2px 4px rgba(0,0,0,0.8);
  border-left: 2px solid var(--color-gold);
  padding-left: 1.5rem;
}

/* Specific Section Customizations */
#sec-intro {
  height: 100vh;
}

#sec-intro .hero-center {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

#sec-intro h1 {
  font-size: 4.5rem;
  font-weight: 800;
  letter-spacing: 1.2rem;
  margin-bottom: 1.5rem;
  color: var(--color-text-main);
  text-shadow: 0 0 30px rgba(0, 0, 0, 0.9);
  line-height: 1.3;
}

#sec-intro h1 span {
  color: var(--color-gold);
  text-shadow: 0 0 20px var(--color-gold-glow);
}

#sec-intro p {
  font-size: 1.2rem;
  letter-spacing: 0.3rem;
  color: var(--color-gold-light);
  margin-bottom: 3rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
  font-weight: 400;
}

.scroll-hint {
  font-family: var(--font-english);
  font-size: 0.7rem;
  letter-spacing: 0.4rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.scroll-hint-line {
  width: 1px;
  height: 60px;
  background: linear-gradient(to bottom, var(--color-gold), transparent);
  animation: scrollLineAnimation 2s infinite ease-in-out;
}

@keyframes scrollLineAnimation {
  0% {
    transform: scaleY(0);
    transform-origin: top;
  }
  50% {
    transform: scaleY(1);
    transform-origin: top;
  }
  50.1% {
    transform: scaleY(1);
    transform-origin: bottom;
  }
  100% {
    transform: scaleY(0);
    transform-origin: bottom;
  }
}

/* Sandbox Panel (Glassmorphism Control Panel) */
.sandbox-controls {
  position: absolute;
  bottom: 5%;
  left: 5%;
  background: rgba(12, 12, 12, 0.65);
  border: 1px solid rgba(197, 160, 89, 0.25);
  border-radius: 16px;
  padding: 2rem;
  width: 320px;
  backdrop-filter: blur(15px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.6);
  z-index: 10;
  transition: var(--transition-smooth);
}

.sandbox-controls:hover {
  border-color: rgba(197, 160, 89, 0.5);
  box-shadow: 0 20px 50px rgba(197, 160, 89, 0.1);
}

.sandbox-title {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.15rem;
  color: var(--color-gold);
  margin-bottom: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(197, 160, 89, 0.15);
  padding-bottom: 0.6rem;
}

.control-group {
  margin-bottom: 1.2rem;
}

.control-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  letter-spacing: 0.1rem;
  color: var(--color-text-muted);
  margin-bottom: 0.5rem;
  font-family: var(--font-english);
}

.control-input-range {
  width: 100%;
  height: 2px;
  background: rgba(255, 255, 255, 0.1);
  outline: none;
  -webkit-appearance: none;
  cursor: pointer;
}

.control-input-range::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--color-gold);
  box-shadow: 0 0 6px var(--color-gold);
  border: 1px solid var(--color-gold-light);
  transition: transform 0.1s;
}

.control-input-range::-webkit-slider-thumb:hover {
  transform: scale(1.3);
}

.button-group {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.5rem;
  margin-top: 1rem;
}

.control-btn {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(197, 160, 89, 0.2);
  color: var(--color-text-main);
  padding: 0.6rem;
  border-radius: 6px;
  font-size: 0.7rem;
  letter-spacing: 0.05rem;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.control-btn:hover, .control-btn.active {
  background: var(--color-gold);
  color: #060606;
  border-color: var(--color-gold-light);
  font-weight: 700;
  box-shadow: 0 0 10px var(--color-gold-glow);
}

/* Calligraphy Text overlay on Canvas */
.calligraphy-bg-text {
  position: absolute;
  font-family: var(--font-japanese);
  font-size: 10vw;
  font-weight: 900;
  color: rgba(255, 255, 255, 0.015);
  writing-mode: vertical-rl;
  z-index: 0;
  pointer-events: none;
  letter-spacing: 2vw;
  line-height: 1;
}

#bg-text-1 { top: 10%; left: 5%; }
#bg-text-2 { top: 20%; right: 10%; }

/* Scroll Lock Message (for horizontal visual layout helper) */
.scroll-progress-indicator {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(to right, var(--color-gold), var(--color-gold-light));
  z-index: 101;
  box-shadow: 0 0 8px var(--color-gold);
}

/* Responsiveness */
@media (max-width: 768px) {
  #sec-intro h1 { font-size: 3rem; letter-spacing: 0.6rem; }
  .vertical-title { font-size: 2.2rem; letter-spacing: 0.5rem; }
  .subtitle-horizontal { font-size: 0.9rem; left: 5%; right: 5%; }
  .sandbox-controls { width: 90%; left: 5%; bottom: 2%; }
  .side-nav { display: none; }
  header { padding: 1.5rem; }
  .logo { font-size: 1.4rem; }
}