remove all ie7 conditionals and mixins

less/buttons.less

@@ -9,21 +9,17 @@
 // Core
 .btn {
   display: inline-block;
-  .ie7-inline-block();
   padding: 4px 12px;
   margin-bottom: 0; // For input.btn
   font-size: @baseFontSize;
   line-height: @baseLineHeight;
-  *line-height: @baseLineHeight;
   text-align: center;
   vertical-align: middle;
   cursor: pointer;
   .buttonBackground(@btnBackground, @btnBackgroundHighlight, @grayDark, 0 1px 1px rgba(255,255,255,.75));
   border: 1px solid @btnBorder;
-  *border: 0; // Remove the border to prevent IE7's black border on input:focus
   border-bottom-color: darken(@btnBorder, 10%);
   .border-radius(4px);
-  .ie7-restore-left-whitespace(); // Give IE7 some love
   .box-shadow(~"inset 0 1px 0 rgba(255,255,255,.2), 0 1px 2px rgba(0,0,0,.05)");
 
   // Hover state
@@ -31,7 +27,6 @@
     color: @grayDark;
     text-decoration: none;
     background-color: darken(@white, 10%);
-    *background-color: darken(@white, 15%); /* Buttons in IE7 don't get borders, so darken on hover */
     background-position: 0 -15px;
 
     // transition is only when going to hover, otherwise the background
@@ -183,22 +178,6 @@ input[type="submit"].btn {
     border: 0;
   }
 
-  // IE7 has some default padding on button controls
-  *padding-top: 3px;
-  *padding-bottom: 3px;
-
-  &.btn-large {
-    *padding-top: 7px;
-    *padding-bottom: 7px;
-  }
-  &.btn-small {
-    *padding-top: 3px;
-    *padding-bottom: 3px;
-  }
-  &.btn-mini {
-    *padding-top: 1px;
-    *padding-bottom: 1px;
-  }
 }