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

:root {
  --bg-color: #f5f0e8;
  --text-color: #2c1810;
  --accent-green: #2d5a3d;
  --accent-gold: #c9a84c;
  --accent-red: #8b3a2a;
  --border-color: #2c1810;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Noto Serif JP', serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)' opacity='0.03'/%3E%3C/svg%3E");
  line-height: 1.8;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 20px;
}

header {
  border-bottom: 1px solid var(--border-color);
  padding: 20px 0;
  margin-bottom: 40px;
  position: relative;
}

header::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 1px;
  background-color: var(--border-color);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  text-decoration: none;
  color: var(--text-color);
  letter-spacing: 0.1em;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo::before {
  content: '';
  display: inline-block;
  width: 20px;
  height: 20px;
  background: currentColor;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M3 21v-4.25L16.2 3.55a1 1 0 0 1 1.41 0l2.84 2.84a1 1 0 0 1 0 1.41L7.25 21H3zm2-2h1.41l9.9-9.91-1.42-1.42L5 17.59V19zM18.66 5.34L17.25 3.93l-1.41 1.41 1.41 1.42 1.41-1.42z'/%3E%3C/svg%3E") no-repeat center / contain;
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M3 21v-4.25L16.2 3.55a1 1 0 0 1 1.41 0l2.84 2.84a1 1 0 0 1 0 1.41L7.25 21H3zm2-2h1.41l9.9-9.91-1.42-1.42L5 17.59V19zM18.66 5.34L17.25 3.93l-1.41 1.41 1.41 1.42 1.41-1.42z'/%3E%3C/svg%3E") no-repeat center / contain;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 20px;
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
  font-size: 0.9rem;
}

nav a {
  text-decoration: none;
  color: var(--text-color);
  letter-spacing: 0.05em;
  transition: color 0.3s, transform 0.3s;
  position: relative;
  display: inline-block;
}

nav a::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 1px;
  bottom: -2px;
  left: 0;
  background-color: var(--accent-gold);
  transform: scaleX(0);
  transform-origin: bottom right;
  transition: transform 0.3s ease-out;
}

nav a:hover {
  color: var(--accent-gold);
  transform: translateY(-2px);
}

nav a:hover::after {
  transform: scaleX(1);
  transform-origin: bottom left;
}

.external-link {
  color: var(--accent-green);
}

main {
  flex: 1;
  padding: 20px 0 60px;
}

footer {
  text-align: center;
  padding: 30px 0;
  border-top: 1px dashed var(--border-color);
  margin-top: 60px;
  font-size: 0.85rem;
  letter-spacing: 0.05em;
}

h1, h2, h3, h4 {
  font-weight: 700;
  margin-top: 0;
  color: var(--text-color);
}

.page-title {
  text-align: center;
  font-size: 2.2rem;
  margin-bottom: 5px;
  letter-spacing: 0.05em;
}

.page-subtitle {
  text-align: center;
  font-size: 1rem;
  color: var(--accent-green);
  margin-bottom: 50px;
  letter-spacing: 0.15em;
}

.section-title {
  font-size: 1.5rem;
  border-bottom: 1px solid var(--accent-gold);
  padding-bottom: 10px;
  margin-bottom: 20px;
  display: inline-block;
}

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

.stamp {
  display: inline-block;
  border: 2px solid var(--accent-red);
  color: var(--accent-red);
  padding: 4px 12px;
  border-radius: 2px;
  text-transform: uppercase;
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  transform: rotate(-3deg);
  opacity: 0.85;
  font-weight: bold;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  margin-top: 30px;
}

.card {
  border: 1px solid var(--border-color);
  padding: 30px 20px;
  text-align: center;
  text-decoration: none;
  color: var(--text-color);
  position: relative;
  transition: transform 0.4s, background-color 0.4s;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  min-height: 120px;
  background-color: rgba(255, 255, 255, 0.4);
}

.card::before {
  content: '';
  position: absolute;
  top: 4px; left: 4px; right: 4px; bottom: 4px;
  border: 1px dashed var(--border-color);
  pointer-events: none;
  opacity: 0.5;
}

.card:hover {
  transform: translateY(-5px);
  background-color: rgba(255, 255, 255, 0.8);
}

.card.disabled {
  opacity: 0.5;
  pointer-events: none;
  background-color: transparent;
}

/* Animations */
.fade-in {
  opacity: 0;
  animation: fadeIn 1s ease-out forwards;
}

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

/* Envelope Intro Animation (Top Page) */
.envelope-overlay {
  position: fixed;
  top: 0; left: 0; width: 100vw; height: 100vh;
  background-color: var(--bg-color);
  z-index: 9999;
  display: flex;
  justify-content: center;
  align-items: center;
  animation: hideOverlay 0.8s forwards;
  animation-delay: 2.5s;
}

.envelope {
  position: relative;
  width: 300px;
  height: 200px;
  background-color: #e2d8c8;
  border: 2px solid var(--border-color);
  box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

.envelope::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  border-left: 150px solid transparent;
  border-right: 150px solid transparent;
  border-top: 100px solid #d4c8b6;
  border-bottom: 100px solid transparent;
  z-index: 2;
  transform-origin: top;
  animation: openFlap 1s forwards;
  animation-delay: 0.5s;
}

.envelope::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  border-left: 150px solid #ecdac5;
  border-right: 150px solid #ecdac5;
  border-bottom: 100px solid #e5d1ba;
  border-top: 100px solid transparent;
  z-index: 1;
}

.envelope-letter {
  position: absolute;
  top: 10px; left: 10px; right: 10px; height: 180px;
  background-color: white;
  border: 1px solid #ccc;
  z-index: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
  box-sizing: border-box;
  animation: pullLetter 1.5s forwards;
  animation-delay: 1.2s;
  font-size: 0.8rem;
  color: var(--text-color);
}

@keyframes openFlap {
  0% { transform: rotateX(0); z-index: 2; }
  100% { transform: rotateX(180deg); z-index: 0; opacity: 0; }
}

@keyframes pullLetter {
  0% { transform: translateY(0); }
  100% { transform: translateY(-120px) scale(1.5); opacity: 0; }
}

@keyframes hideOverlay {
  0% { opacity: 1; visibility: visible; }
  100% { opacity: 0; visibility: hidden; }
}

.catchphrase {
  text-align: center;
  font-size: 1.2rem;
  margin: 40px 0;
  padding: 30px;
  border-top: 1px solid var(--accent-gold);
  border-bottom: 1px solid var(--accent-gold);
  background: rgba(255, 255, 255, 0.3);
  font-style: italic;
  letter-spacing: 0.05em;
  line-height: 2;
}

@media (max-width: 600px) {
  nav ul {
    justify-content: center;
  }
  .header-inner {
    flex-direction: column;
    text-align: center;
  }
  .logo {
    justify-content: center;
  }
}

.btn {
  display: inline-block;
  padding: 8px 16px;
  background-color: var(--bg-color);
  border: 1px solid var(--accent-gold);
  color: var(--text-color);
  text-decoration: none;
  font-size: 0.85rem;
  border-radius: 4px;
  transition: all 0.3s ease;
  text-align: center;
}
.btn:hover {
  background-color: var(--accent-gold);
  color: #fff;
}
.btn.disabled {
  border-color: #ccc;
  color: #888;
  pointer-events: none;
  background-color: transparent;
}
.custom-audio {
  width: 100%;
  border-radius: 4px;
  outline: none;
  filter: sepia(0.5) hue-rotate(-30deg) saturate(0.8) opacity(0.9);
}
.audio-wrapper {
  margin-top: 15px;
  text-align: left;
}

/* Character Items */
.character-item {
  margin-bottom: 20px;
  padding: 20px;
  cursor: pointer;
  transition: background-color 0.3s, transform 0.3s;
  border-radius: 8px;
}
.character-item:hover {
  background-color: rgba(255, 255, 255, 0.5);
  transform: translateX(5px);
}

/* Modal */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background-color: rgba(44, 24, 16, 0.8);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}
.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}
.modal-content {
  background-color: var(--bg-color);
  border: 2px solid var(--border-color);
  border-radius: 4px;
  width: 90%;
  max-width: 600px;
  max-height: 90vh;
  overflow-y: auto;
  position: relative;
  padding: 40px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.5);
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)' opacity='0.03'/%3E%3C/svg%3E");
}
.modal-close {
  position: absolute;
  top: 15px; right: 20px;
  font-size: 2rem;
  cursor: pointer;
  color: var(--text-color);
  line-height: 1;
}
.modal-close:hover {
  color: var(--accent-red);
}
.modal-image-placeholder {
  width: 100%;
  height: 400px;
  background-color: var(--bg-color);
  border: 1px dashed var(--border-color);
  display: flex;
  justify-content: center;
  align-items: center;
  color: #888;
  margin-bottom: 20px;
  border-radius: 4px;
  font-size: 0.9rem;
}
.modal-image {
  width: 100%;
  height: 400px;
  object-fit: contain;
  background-color: var(--bg-color);
  border: 1px solid var(--border-color);
  margin-bottom: 20px;
  border-radius: 4px;
  display: none;
}