[bugfix] Step: fit small screen

packages/step/index.less

@@ -26,7 +26,7 @@
 
     &:last-child {
       position: absolute;
-      right: 10px;
+      right: 1px;
       width: auto;
 
       .van-step__title {
@@ -54,6 +54,10 @@
       transform: translate3d(-50%, 0, 0);
       display: inline-block;
       margin-left: 3px;
+
+      @media(max-width: 321px) {
+        font-size: 11px;
+      }
     }
 
     .van-step__line {

packages/steps/index.less

@@ -10,7 +10,6 @@
     .van-steps__items {
       display: flex;
       margin: 0 0 10px;
-      overflow: hidden;
       position: relative;
       padding-bottom: 22px;