Use @font-size-... variables instead of hardcoded font-size in px

docs/assets/css/bootstrap.css

@@ -3192,9 +3192,9 @@ a.list-group-item.active .list-group-item-text {
 
 .close {
   float: right;
-  font-size: 20px;
+  font-size: 21px;
   font-weight: bold;
-  line-height: 20px;
+  line-height: 1;
   color: #000;
   text-shadow: 0 1px 0 #ffffff;
   opacity: 0.2;
@@ -3382,7 +3382,7 @@ button.close {
 .nav-header {
   display: block;
   padding: 3px 15px;
-  font-size: 11px;
+  font-size: 10.5px;
   font-weight: bold;
   line-height: 20px;
   color: #999999;
@@ -3576,7 +3576,7 @@ button.close {
   padding: 15px;
   margin-right: auto;
   margin-left: auto;
-  font-size: 18px;
+  font-size: 17.5px;
   font-weight: 500;
   line-height: 20px;
   color: #777777;
@@ -4355,7 +4355,7 @@ button.close {
   position: absolute;
   z-index: 1030;
   display: block;
-  font-size: 11px;
+  font-size: 10.5px;
   line-height: 1.4;
   opacity: 0;
   filter: alpha(opacity=0);
@@ -4802,7 +4802,7 @@ a.thumbnail:focus {
   display: inline-block;
   min-width: 10px;
   padding: 3px 7px;
-  font-size: 12px;
+  font-size: 11.9px;
   font-weight: bold;
   line-height: 1;
   color: #fff;
@@ -4902,7 +4902,7 @@ a.list-group-item.active > .badge,
   float: left;
   width: 0;
   height: 100%;
-  font-size: 12px;
+  font-size: 11.9px;
   color: #fff;
   text-align: center;
   text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.25);
@@ -5216,7 +5216,7 @@ a.list-group-item.active > .badge,
     border-radius: 6px;
   }
   .jumbotron h1 {
-    font-size: 60px;
+    font-size: 63px;
   }
 }
 

less/badges.less

@@ -8,7 +8,7 @@
   display: inline-block;
   min-width: 10px;
   padding: 3px 7px;
-  font-size: 12px;
+  font-size: @font-size-small;
   font-weight: bold;
   color: #fff;
   line-height: 1;

less/close.less

@@ -5,9 +5,9 @@
 
 .close {
   float: right;
-  font-size: 20px;
+  font-size: (@font-size-base * 1.5);
   font-weight: bold;
-  line-height: @line-height-base;
+  line-height: 1;
   color: #000;
   text-shadow: 0 1px 0 rgba(255,255,255,1);
   .opacity(.2);

less/jumbotron.less

@@ -6,7 +6,7 @@
 .jumbotron {
   padding: 30px;
   margin-bottom: 30px;
-  font-size: 21px;
+  font-size: (@font-size-base * 1.5);
   font-weight: 200;
   line-height: (@line-height-base * 1.5);
   color: @jumbotron-lead-color;
@@ -26,7 +26,7 @@
     border-radius: @border-radius-large; // Only round corners at higher resolutions
 
     h1 {
-      font-size: 60px;
+      font-size: (@font-size-base * 4.5);
     }
   }
 }

less/navbar.less

@@ -83,7 +83,7 @@
   margin-left: auto;
   margin-right: auto;
   padding: 15px;
-  font-size: 18px;
+  font-size: @font-size-large;
   font-weight: 500;
   line-height: @line-height-base;
   color: @navbar-brand-color;

less/navs.less

@@ -183,7 +183,7 @@
 .nav-header {
   display: block;
   padding: 3px 15px;
-  font-size: 11px;
+  font-size: @font-size-mini;
   font-weight: bold;
   line-height: @line-height-base;
   color: @gray-light;

less/popovers.less

@@ -34,7 +34,7 @@
 .popover-title {
   margin: 0; // reset heading margin
   padding: 8px 14px;
-  font-size: 14px;
+  font-size: @font-size-base;
   font-weight: normal;
   line-height: 18px;
   background-color: @popover-title-bg;

less/progress-bars.less

@@ -56,7 +56,7 @@
   float: left;
   width: 0%;
   height: 100%;
-  font-size: 12px;
+  font-size: @font-size-small;
   color: #fff;
   text-align: center;
   text-shadow: 0 -1px 0 rgba(0,0,0,.25);

less/tooltip.less

@@ -9,7 +9,7 @@
   z-index: @zindex-tooltip;
   display: block;
   visibility: visible;
-  font-size: 11px;
+  font-size: @font-size-mini;
   line-height: 1.4;
   .opacity(0);