Update global typography

Updated the following body, label, and heading
styles to match new style guide:
- Font sizes
- Font weight
- Line height
- Color

Signed-off-by: Dixsie Wolmers <dixsie@ibm.com>
Change-Id: I014c968f6542b697fec8c3b9af781e64ac10794d
diff --git a/src/assets/styles/bmc/custom/_base.scss b/src/assets/styles/bmc/custom/_base.scss
index 5a6a11b..c11e046 100644
--- a/src/assets/styles/bmc/custom/_base.scss
+++ b/src/assets/styles/bmc/custom/_base.scss
@@ -4,4 +4,47 @@
   color: gray("800");
   font-size: 14px;
   font-weight: 400;
+  line-height: 1.4285;
+}
+
+h1,
+.h1 {
+  font-size: 2.625rem;
+  font-weight: 300;
+  line-height: 1.238;
+}
+
+h2,
+.h2 {
+  font-size: 2.25rem;
+  font-weight: 300;
+  line-height: 1.3333;
+}
+
+h3,
+.h3 {
+  font-size: 1.75rem;
+  font-weight: 400;
+  line-height: 1.2857;
+}
+
+h4,
+.h4 {
+  font-size: 1.25rem;
+  font-weight: 400;
+  line-height: 1.3;
+}
+
+h5,
+.h5 {
+  font-size: 1rem;
+  font-weight: 500;
+  line-height: 1.375;
+}
+
+h6,
+.h6 {
+  font-size: 0.875rem;
+  font-weight: 500;
+  line-height: 1.2857;
 }