header {
  position: fixed;
  top: 0;
  width: 100%;
  height: 62px;
  background-color: rgb(45, 47, 51);
}

header .mid {
  width: 1200px;
  margin: 0 auto;
  color: white;
}
/* logo */
header .mid .logo {
  float: left;
  width: 270px;
  margin: 15px auto;
}

header .mid .logo img {
  height: 32px;
  vertical-align: middle;
}

header .mid .logo strong {
  margin: 10px;
}

header .mid .logo strong::before {
  content: '|';
}
/* list */
header .mid .list {
  float: left;
  width: calc(68 * 6 + 82)+'px';
  list-style: none;
}

header .mid .list li {
  float: left;
  width: 68px;
  height: 62px;
  line-height: 62px;
  text-align: center;
}

header .mid .list li:hover {
  background-color: rgb(83, 85, 88);
}
/* user */
header .mid .user {
  float: right;
  width: 327px;
}

header .mid .user form {
  float: left;
  width: 99px;
  margin-top: 15px;
}

header .mid .user form input {
  width: 99px;
  height: 30px;
  outline: none;
  border-radius: 15px;
  background-color: rgb(83, 85, 88);
}

header .mid .user form input:focus {
  margin-left: -21px;
  width: 120px;
  caret-color: transparent;
}

header .mid .user .focus, header .mid .user .message {
  float: left;
  width: 68px;
  height: 62px;
  text-align: center;
  line-height: 62px;
}

header .mid .user .focus:hover {
  background-color: rgb(83, 85, 88);
}

header .mid .user .message:hover {
  background-color: rgb(83, 85, 88);
}

header .mid .user .userInfo {
  float: right;
  width: 82px;
  height: 62px;
  text-align: center;
  line-height: 62px;
}

header .mid .user .userInfo a img {
  height: 32px;
  vertical-align: middle;
  border-radius: 16px;
}