* {
  box-sizing: border-box;
}
body {
  font-family: Roboto, "HarmonyOS Sans SC", "Noto Sans SC", sans-serif;
  font-size: 16px;
  margin: 0;
  overflow: hidden;
  position: fixed;
  width: 100vw;
  height: 100vh;
  left: 0;
  top: 0;
}

section .logo-container {
  width: 600px;
  height: 100vh;
  margin: auto;
  display: flex;
  justify-content: center;
  flex-direction: row;
  align-items: center;
}
@media screen and (max-width: 640px) {
  section .logo-container {
    width: 90vw;
    height: 55vh;
    height: max-content;
    padding-top: 15vh;
  }
}
section .logo-container .logo {
  border-radius: 18px;
  width: 128px;
  height: 128px;
  overflow: hidden;
  box-shadow: 6px 6px 12px 0 rgba(0, 0, 0, 0.3);
}
section .logo-container .logo img {
  width: 100%;
  height: 100%;
}
section .logo-container .link {
  margin-left: 1em;
}
section .logo-container .link .serif {
  font-family: "Noto Serif SC", serif;
}
section .logo-container .link h1 {
  font-weight: 900;
  font-size: 1.75em;
  margin-top: 0;
  margin-bottom: 0.25em;
}
@media screen and (max-width: 640px) {
  section .logo-container .link h1 {
    font-size: 1.5em;
  }
}
section .logo-container .link h3 {
  margin-top: 0;
  margin-bottom: 0.25em;
}
section .logo-container .link p {
  margin: 0.25em 0;
}

section .logo-container .button-group {
  display: flex;
  justify-content: flex-end;
  gap: 0 0.5em;
}

section .logo-container .link a.button {
  display: block;
  border: 1px solid #e0e0e0;
  outline: none;
  padding: 0.75em 1em;
  border-radius: 8px;
  background-color: #204b81;
  color: #ffffff;
  font-size: 1em;
  font-weight: 500;
  text-decoration: none;
}

section .logo-container .link a.button.video {
  background-color: #ff6600;
}

section .logo-container .link a.button:visited,
section .logo-container .link a.button:active,
section .logo-container .link a.button:focus {
  text-decoration: none;
}
section.background-container {
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  position: fixed;
  top: 0;
  left: 0;
  z-index: -1;
}
section.background-container .background {
  position: absolute;
  width: 160vw;
  top: -40vh;
  left: -30vw;
  height: 180vh;
  overflow: visible;
  transform: rotateZ(340deg) rotateX(45deg) rotateY(18deg);
  font-size: 128px;
  color: #e7e7e7;
  line-height: 144px;
  writing-mode: vertical-rl;
  font-family: "Noto Serif SC", serif;
  letter-spacing: 0.25em;
}

section.background-container .background.ready {
  opacity: 0;
}

section.background-container .background.fade-in {
  animation-name: animation-fade-in;
  animation-timing-function: ease-in-out;
  animation-duration: 1.5s;
  animation-fill-mode: forwards;
  animation-iteration-count: 1;
}
section.background-container .background.fade-out {
  animation-name: animation-fade-out;
  animation-timing-function: ease-in-out;
  animation-duration: 2s;
  animation-fill-mode: forwards;
  animation-iteration-count: 1;
}

@media screen and (max-width: 640px) {
  section.background-container .background {
    width: 180vw;
    top: -35vh;
    left: -40vw;
    height: 170vh;
    font-size: 20vw;
    line-height: 25vw;
    letter-spacing: 0.25em;
  }
}

@keyframes animation-fade-in {
  0% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}
@keyframes animation-fade-out {
  0% {
    opacity: 1;
  }

  100% {
    opacity: 0;
  }
}

footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
}
footer p {
  text-align: center;
  color: #666888;
  font-size: 0.875em;
}