header {
    border-bottom: 1px solid #ccc;
  }
header #nav_area {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1000px;
  width: 90%;
  margin: 0 auto;
  padding: 5px 0;
}
header .logo {
  text-decoration: none;
  font-size: 1.5rem;
  font-weight: 600;
}
header .avatar {
  border-radius: 2rem;
  height: 2.2rem;
  width: 2.2rem;
  background-color: white;
  background-size: cover;
  border: 2px solid #ddd;
}
header .email {
  margin-right: 1rem;
  margin-left: 0.25rem;
  font-weight: 600;
  line-height: 35px;
}
header .signInButton,
header .signOutButton {
  color: #fff;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 1rem;
  padding: 0.5rem 1rem;
}
header .signInButton {
  background-color: #1eb1fc;
}
header .signInButton:hover {
  background-color: #1b9fe2;
}
header .signOutButton {
  background-color: #333;
}
header .signOutButton:hover {
  background-color: #555;
}
header .icon_box {
  height: 2.5rem;
  cursor: pointer;
  width: 45px;
}
header .account_info {
  display: flex;
}
header .paper {
  margin-right: 10px;
  border: 1px solid #d3d4d5;
}
header .menu_top {
  width: 180px;
  text-align: center;
  margin: 0 auto;
}
header .in_menu_top {
  white-space: nowrap;
  text-overflow: ellipsis;
  overflow: hidden;
  margin-bottom: 0;
}