ui.css

*, *:before, *.after {
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

.bg-black { background-color: #333333; }
.bg-white { background-color: #f6f6f6; }
.bg-gray { background-color: #aaaaaa; }
.bg-silver { background-color: #dddddd; }
.bg-red { background-color: #e54d42; }
.bg-green { background-color: #1abc9c; }
.bg-yellow { background-color: #FFDC00; }
.bg-blue { background-color: #3498db; }
.bg-navy { background-color: #34495e; }
.bg-orange { background-color: #e67e22; }
.bg-orangered { background-color: #d35400; }
.bg-purple { background-color: #9b59b6; }

.bd-black { border-color: #333333;}
.bd-white { border-color: #f6f6f6;}
.bd-gray { border-color: #aaaaaa;}
.bd-silver { border-color: #dddddd;}
.bd-red { border-color: #e54d42;}
.bd-green { border-color: #1abc9c;}
.bd-yellow { border-color: #FFDC00;}
.bd-blue { border-color: #3498db;}
.bd-navy { border-color: #34495e;}
.bd-orange { border-color: #e67e22;}
.bd-orangered { border-color: #d35400;}
.bd-purple { border-color: #9b59b6;}

html {
  font-size: 20px;
  font-family: Georgia, "Times New Roman", "Microsoft YaHei", "微软雅黑", STXihei, "华文细黑", serif;
}
@media screen and (max-width: 768px) {
  html {
    font-size: 16px;
  }
}

h1 { font-size: 2em; }
h2 { font-size: 1.5em; }
h3 { font-size: 1.17em; }
h4 { font-size: 1em; }
h5 { font-size: 0.83em; }
h6 { font-size: 0.67em; }

h1, h2, h3, h4, h5, h6 {
  padding: 0.5em;
  margin: 0;
}

input {
  border-radius: 1px;
  border: 1px solid #dddddd;
  font-size: 1rem;
  padding: 0.3rem 0.5rem;
}

.center {
  text-align: center;
}

.container {
  width: 70%;
  margin: 0 auto;
}
.container-fluid {
  width: 100%;
}

.button {
  display: inline-block;
  font-size: 1rem;
  padding: 0.3rem 0.5rem;
  margin: 5px;
  border: 1px solid #dddddd;
  border-radius: 1px;
  cursor: pointer;
}