update input-group style

style/components/form.less

 @import "../mixins/index";
+@btnClass: ~"@{css-prefix}btn";
 
 .reset-form();
 
@@ -45,26 +46,21 @@ label {
 
 //== Style for input-group
 .@{css-prefix}input-group {
-  .input-group(~"@{css-prefix}input");
+  .input-group(~"@{css-prefix}input"; @btnClass)
 }
 
 // 表单下的输入框尺寸唯一: 大尺寸
 form {
-  .@{css-prefix}input {
-    height: @input-height-lg;
-    font-size: @font-size-base;
-    padding: @input-padding-horizontal;
-  }
   .has-feedback {
     .@{iconfont-css-prefix} {
       .square(@input-height-lg);
       line-height: @input-height-lg;
     }
   }
-
-  .@{css-prefix}input-group > .@{css-prefix}input,
-  .@{css-prefix}input-group > .@{css-prefix}input-group-addon,
-  .@{css-prefix}input-group > .@{css-prefix}input-group-btn > .input-btn {
+  .@{css-prefix}input,
+  .@{css-prefix}input-group .@{css-prefix}input,
+  .@{css-prefix}input-group .@{css-prefix}input-group-addon,
+  .@{css-prefix}input-group .@{css-prefix}input-group-btn .@{btnClass} {
     height: @input-height-lg;
     font-size: @font-size-base;
     padding: @input-padding-horizontal;

style/mixins/input.less

@@ -17,8 +17,8 @@
   display: inline-block;
   padding: @input-padding-vertical-base @input-padding-horizontal;
   width: 100%;
-  cursor: text;
   height: @input-height-base;
+  cursor: text;
   font-size: @input-font-size;
   line-height: @line-height-base;
   color: @input-color;
@@ -85,11 +85,8 @@
   }
 }
 
-// Input-group
-.input-group(@inputClass) {
-  // define the button style for input-group
-  @inputBtn: input-btn;
-
+// label input
+.input-group(@inputClass; @btnclass) {
   position: relative;
   display: table;
   border-collapse: separate;
@@ -101,10 +98,7 @@
     padding-right: 0;
   }
 
-  &-addon,
-  &-btn,
-  &-btn-vertical,
-  .@{inputClass} {
+  &-addon, &-btn, .@{inputClass} {
     display: table-cell;
 
     &:not(:first-child):not(:last-child) {
@@ -112,9 +106,7 @@
     }
   }
 
-  &-addon,
-  &-btn,
-  &-btn-vertical {
+  &-addon, &-btn {
     width: 1%;
     white-space: nowrap;
     vertical-align: middle;
@@ -138,24 +130,18 @@
     background-color: #eee;
     border: 1px solid @input-border-color;
     border-radius: @border-radius-base;
-
-    input[type="radio"],
-    input[type="checkbox"] {
-      margin-top: 0;
-    }
   }
 
-  .@{inputBtn} {
-    .btn();
-    .button-size(@input-padding-vertical-base @input-padding-horizontal; @font-size-base; @border-radius-base);
+  .@{btnclass} {
+    border-radius: @border-radius-base;
     .button-variant(@input-color; #eee; @input-border-color);
+    margin-left: -1px;
 
     &:hover {
-      .button-color(tint(@input-color, 20%); #eee; @input-border-color);
+      .button-color(@input-color; tint(#eee, 20%); @input-border-color);
     }
-    &:active,
-    &.active {
-      .button-color(shade(@input-color, 5%); #eee; @input-border-color);
+    &:active, &.active {
+      .button-color(@input-color; shade(#eee, 5%); @input-border-color);
     }
 
     .@{iconfont-css-prefix} {
@@ -164,34 +150,8 @@
     }
   }
 
-  &-btn {
-    position: relative;
-
-    > .@{inputBtn} {
-      position: relative;
-      + .@{inputBtn} {
-        margin-left: -1px;
-      }
-    }
-
-    // Negative margin to only have a 1px border between the two
-    &:first-child {
-      > .@{inputBtn} {
-        margin-right: -1px;
-      }
-    }
-    &:last-child {
-      > .@{inputBtn} {
-        margin-left: -1px;
-      }
-    }
-  }
-
   // Reset rounded corners
-  .@{inputClass}:first-child,
-  &-addon:first-child,
-  &-btn:first-child > .@{inputBtn},
-  &-btn:last-child > .@{inputBtn}:not(:last-child):not(.dropdown-toggle) {
+  .@{inputClass}:first-child, &-addon:first-child {
     border-bottom-right-radius: 0;
     border-top-right-radius: 0;
   }
@@ -199,33 +159,31 @@
   &-addon:first-child {
     border-right: 0;
   }
+  &-addon:last-child {
+    border-left: 0;
+  }
 
   .@{inputClass}:last-child,
   &-addon:last-child,
-  &-btn:last-child > .@{inputBtn},
-  &-btn:first-child > .@{inputBtn}:not(:first-child) {
+  &-btn .@{btnclass}{
     border-bottom-left-radius: 0;
     border-top-left-radius: 0;
   }
 
-  &-addon:last-child {
-    border-left: 0;
-  }
-
   // Sizing options
   &-lg > .@{inputClass},
   &-lg > &-addon,
-  &-lg > &-btn > .@{inputBtn} {
+  &-lg > &-btn .@{btnclass} {
     .input-lg();
   }
 
   &-sm > .@{inputClass},
   &-sm > &-addon,
-  &-sm > &-btn > .@{inputBtn} {
+  &-sm > &-btn .@{btnclass} {
     .input-sm();
   }
 
-  &-sm > &-btn > .@{inputBtn} {
+  &-sm > &-btn .@{btnclass} {
     margin-top: ~"-2px \9";
   }
 }