body{
	background: #000;
	color: #fff;
	width: 86%;
	margin: 0 auto;
}
a {
	color: #fff;
	text-decoration: none;
}
p,h1,h2,h3,h4,h5,h6 {
	margin: 0;
	padding:0;
}
.cb {
	clear: both;
}
.hide {
	display: none;
}
.vhide{
	visibility: hidden;
}
.tcenter {
	text-align: center;
}
 
@keyframes dot {
    0% { width: 0; margin-right: 1.5em; }
    33% { width: .5em; margin-right: 1em; }
    66% { width: 1em; margin-right: .5em; }
    100% { width: 1.5em; margin-right: 0;}
}
.ani_dot {
    animation: dot 3s infinite step-start;
}
/* 加载中...*/
#loading{
	display: inline-block;
	margin-bottom: 30px;
	position: absolute;
	left: 500px;
	top:500px;
	height: 30px;
	width: 30px;
	border-radius: 50%;
	border: 2px solid dodgerblue;
	border-bottom-color: transparent;
	-webkit-animation: loadingRotate 0.75s linear infinite;
	animation: loadingRotate 0.75s linear infinite;
}
#cover {
	position: fixed;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	background: rgba(255,255,255,0.3);
}
@-webkit-keyframes loadingRotate {
  0% {
    -webkit-transform: rotate(0deg);
  }
  50% {
    -webkit-transform: rotate(180deg);
  }
  100% {
    -webkit-transform: rotate(360deg);
  }
}
@keyframes loadingRotate {
  0% {
    transform: rotate(0deg);
  }
  50% {
    transform: rotate(180deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

/* 根号 */
.root-symbol {
  position: relative;
  display: inline-block;
}
.root-symbol .text {
	position: absolute;
}
.root-symbol .text:nth-child(1){
	border-top: 1.5px solid #fff;
	/* top: 0.16em; */
	top: 3px;
	left: 1.1em;
}
.root-symbol .text:nth-child(2){
	top: -5px;
	/* top: -0.1em; */
	left: -0.6em;
}
.root-long {
	width: 4.3em;
}
/* 分子分母 */
.fenzifenmu {
	width: 1em;
	height: 1em;
	position: relative;
	top: 0.15em;
	left: 0.1em;
}