* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html,body {
  color: #333;
  font-size: 14px;
}
img {
  vertical-align: middle;
}
a {
  text-decoration: none;
}
input {
  border: 0;
  outline: none;
}
.bold {
  font-weight: bold;
}
.c-9 {
  color: #999999;
}
.t-c {
  text-align: center;
}
.bg-white {
  background: #fff;
}
.f {
  display: flex;
}
.f1 {
  flex: 1;
}
.f-a-c {
  align-items: center;
}
.f-j-s {
  justify-content: space-between;
}
.mask {
  flex-direction: column;
  display: flex;
  /* justify-content: space-between; */
  z-index: 999;
  position: fixed;
  left: 0;
  top: 100%;
  background: rgba(0, 0, 0, .5);
  width: 100%;
  height: 100%;
}