body {
  margin: 0;
  font-family: Source Han Sans CN;
  font-size: 16px;
}
html {
  background: #f6f9fd;
}
.flex-between-c {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.flex-c {
  display: flex;
  align-items: center;
}
.flex-c-c {
  display: flex;
  justify-content: center;
  align-items: center;
}
.flex-column-c-c {
  display: flex;
  flex-flow: column;
  justify-content: center;
  align-items: center;
}