@font-face {
    font-family: 'jost';
    src: url('https://kokyujene.github.io/fonts/Jost-Bold.ttf') format('truetype');
    font-weight: bold;
    font-style: normal;
}

@font-face {
    font-family: 'jost';
    src: url('https://kokyujene.github.io/fonts/Jost.ttf') format('truetype');
    font-weight: normal;
    font-style: normal;
}

@font-face {
    font-family: 'zenkaku';
    src: url('https://kokyujene.github.io/fonts/zenkaku.ttf') format('truetype');
    font-weight: normal;
    font-style: normal;
}

@font-face {
    font-family: 'zenkaku';
    src: url('https://kokyujene.github.io/fonts/zenkaku-Bold.ttf') format('truetype');
    font-weight: bold;
    font-style: normal;
}

* {
  font-family: 'jost', 'zenkaku', sans-serif;
}

body {
  margin: 0;
  background-color: #fff;
}

.container {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  padding-top: 50vh;
}

.box {
  margin-bottom: 80vh;
  text-align: center;
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 1.2s ease-out, transform 1.2s ease-out;
}

.box.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.title { 
  font-size: 2rem; 
  margin: 0; 
}

.sub-title { 
  font-size: 1rem; 
  color: gray; 
  margin-top: 10px; 
}

.section-title { 
  font-size: 1.5rem; 
  margin: 0; 
}

.description { 
  font-size: 1.1rem; 
  line-height: 1.8; 
  max-width: 600px; 
  margin: 0 auto; 
}

.game-list,
.lang-list {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;
  justify-content: center;
  max-width: 700px;
  margin: 0 auto;
}

a {
  text-decoration: none;
  color: inherit;
  position: relative;
  display: inline-block;
}

a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 50%;
  width: 0;
  height: 1px;
  background-color: currentColor;
  transition: width 0.3s ease, left 0.3s ease;
}

a:hover::after {
  width: 100%;
  left: 0;
}

.game-item,
.lang-item {
  background-color: #f0f0f0;
  border-radius: 20px;
  font-size: 0.95rem;
  transition: all 0.3s ease;
  cursor: pointer;
}

.game-item a {
  padding: 10px 20px;
}

.game-item a::after {
  bottom: 8px;
  left: 50%;
}

.game-item a:hover::after {
  width: calc(100% - 40px);
  left: 20px;
}

.lang-item {
  padding: 10px 20px;
}

.game-item:hover,
.lang-item:hover {
  background-color: #e0e0e0;
  transform: translateY(-2px);
}

.lang-item small {
  font-size: 0.75rem;
  color: #666;
  margin-left: 5px;
}

.footer {
  font-size: 0.85rem;
  color: #999;
  margin-top: 20px;
  padding: 0 20px;
}

.scroll-indicator {
  margin-top: 60px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 15px;
  color: #ccc;
  font-size: 0.7rem;
  letter-spacing: 0.2em;
}

.scroll-indicator .line {
  width: 1px;
  height: 80px;
  background: linear-gradient(to bottom, #ccc, transparent);
  position: relative;
  overflow: hidden;
}

.scroll-indicator .line::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: white;
  animation: scroll-line 2.5s cubic-bezier(0.15, 0, 0.45, 1) infinite;
}

@keyframes scroll-line {
  0% { transform: translateY(-100%); }
  50% { transform: translateY(0); }
  100% { transform: translateY(100%); }
}

/* モバイル対応 */
@media screen and (max-width: 768px) {

  .box {
    margin-bottom: 60vh;
    padding: 0 20px;
    width: 100%;
    box-sizing: border-box;
  }

  .title {
    font-size: 1.6rem;
  }

  .section-title {
    font-size: 1.3rem;
  }

  .description {
    font-size: 1rem;
  }

  .game-item,
  .lang-item {
    font-size: 0.85rem;
    padding: 8px 15px;
  }

  .game-item a {
    padding: 8px 15px;
  }

  .game-item a::after {
    bottom: 6px;
  }

  .game-item a:hover::after {
    width: calc(100% - 30px);
    left: 15px;
  }
}