Reorganize v3 docs CSS to use Less

docs/assets/less/masthead.less

@@ -0,0 +1,72 @@
+/*
+ * Homepage
+ *
+ * Tweaks to the custom homepage and the masthead (main jumbotron).
+ */
+
+/* Share masthead with page headers */
+.bs-docs-masthead,
+.bs-docs-header {
+  position: relative;
+  padding: 30px 0;
+  color: #cdbfe3;
+  text-align: center;
+  text-shadow: 0 1px 0 rgba(0,0,0,.1);
+  background-color: #6f5499;
+  background-image: -webkit-gradient(linear, left top, left bottom, from(#563d7c), to(#6f5499));
+  background-image: -webkit-linear-gradient(top, #563d7c 0%, #6f5499 100%);
+  background-image:      -o-linear-gradient(top, #563d7c 0%, #6f5499 100%);
+  background-image:         linear-gradient(to bottom, #563d7c 0%, #6f5499 100%);
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#563d7c', endColorstr='#6F5499', GradientType=0);
+  background-repeat: repeat-x;
+}
+
+/* Masthead (headings and download button) */
+.bs-docs-masthead .bs-docs-booticon {
+  margin: 0 auto 30px;
+}
+.bs-docs-masthead h1 {
+  font-weight: 300;
+  line-height: 1;
+  color: #fff;
+}
+.bs-docs-masthead .lead {
+  margin: 0 auto 30px;
+  font-size: 20px;
+  color: #fff;
+}
+.bs-docs-masthead .version {
+  margin-top: -15px;
+  margin-bottom: 30px;
+  color: #9783b9;
+}
+.bs-docs-masthead .btn {
+  width: 100%;
+  padding: 15px 30px;
+  font-size: 20px;
+}
+
+@media (min-width: 480px) {
+  .bs-docs-masthead .btn {
+    width: auto;
+  }
+}
+
+@media (min-width: 768px) {
+  .bs-docs-masthead {
+    padding: 80px 0;
+  }
+  .bs-docs-masthead h1 {
+    font-size: 60px;
+  }
+  .bs-docs-masthead .lead {
+    font-size: 24px;
+  }
+}
+
+@media (min-width: 992px) {
+  .bs-docs-masthead .lead {
+    width: 80%;
+    font-size: 30px;
+  }
+}