底部按钮样式调整

src/less/base.less

@@ -52,6 +52,7 @@
   box-shadow:0px -2px 10px 0px rgba(0,0,0,0.06);
   display: flex;
   justify-content: space-between;
+  overflow: hidden;
   .back,.next{
     display: inline-block;
     height: .88rem;
@@ -64,11 +65,13 @@
   }
   .back{
     width: 48%;
+    float: left;
     color: #colors[theme];
   }
   .next{
     width: 48%;
     color: #fff;
+    float: right;
     background: #colors[theme];
   }
 }