bootstrap重新设计按钮样式

1.将btn的样式换成以下的样式

2.思路：

（1）将原来的btn样式设置color：#FFF，同时text-shadow设置，这样原来的btn样式就会变淡了，后面再加上新的样式就可以覆盖掉

注意：要将active，hover，focus都设置成一样的。

（2）加上新的btn样式，对active，hover，focus分别进行设置

源码：

HTML：

<div class="text-center bk-margin-top-10 bk-margin-bottom-30">
	<a class="btn btn-facebook bk-margin-bottom-15 bk-margin-5">Connect with <i class="fa fa-facebook"></i> </a>
	<a class="btn btn-twitter bk-margin-bottom-15 bk-margin-5">Connect with <i class="fa fa-twitter"></i> </a>
</div>

CSS：

/* Buttons
=================================================================== */
.btn {
	display: inline-block;
	margin-bottom: 0;
	font-size: 14px;
	font-weight: normal;
	line-height: 1.42857143;
	text-align: center;
	white-space: nowrap;
	vertical-align: middle;
	cursor: pointer;
	-webkit-user-select: none;
	-moz-user-select: none;
	-ms-user-select: none;
	user-select: none;
	background-image: none;
	border: none;
	border-radius: 3px;
	border-bottom:2px solid rgba(0,0,0,0.2);
}
.btn:focus,
.btn:active:focus,
.btn.active:focus {
	outline: thin dotted;
	outline: 5px auto -webkit-focus-ring-color;
	outline-offset: -2px;
}
.btn:hover,
.btn:focus {
	color: #333;
	text-decoration: none;
}
.btn:active,
.btn.active {
	background-image: none;
	outline: 0;
	-webkit-box-shadow: inset 0 3px 5px rgba(0, 0, 0, .125);
	box-shadow: inset 0 3px 5px rgba(0, 0, 0, .125);
}
/* facebook & twitter的btn
=================================================================== */
.btn:focus,
.btn:active:focus,
.btn.active:focus {
	outline: none;
}
.btn {
	white-space: normal;
}
.btn i {
	margin-top: 2px;
}
/*
先将原先的btn-facebook，btn-twitter的样式通过text-shadow，color隐藏，但是要将字体和padding先设置好
*/
.btn-facebook, .btn-facebook:active, .btn-facebook:hover, .btn-facebook:focus,
.btn-twitter,
.btn-twitter:active,
.btn-twitter:hover,
.btn-twitter:focus {
	color: #FFF;
	font-weight: 300;
	padding-left: 30px;
	padding-right: 30px;
	text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.2);
}
.btn-facebook, .btn-facebook:focus {
	background: #3B5998;
	border: 1px solid #37538D;
}
.btn-facebook:hover {
	background: #4162a7;
	border-color: #3d5c9c;
}
.btn-facebook:active {
	background: #37538d;
	border-color: #334d82;
}

.btn-twitter, .btn-twitter:focus {
	background: #55ACEE;
	border: 1px solid #47A5ED;
}
.btn-twitter:hover {
 	background: #63b3ef;
	border-color: #55acee;
 }
.btn-twitter:active {
	background: #47a5ed;
	border-color: #399eec;
}
.bk-margin-top-10 {
	margin-top: 10px !important;
}
.bk-margin-bottom-30 {
	margin-bottom: 30px !important;
}
.bk-margin-bottom-15 {
	margin-bottom: 15px !important;
}
.bk-margin-5 {
	margin: 5px !important;
}