updated demo

css/gh-fork-ribbon.css

@@ -0,0 +1,127 @@
+/* Left will inherit from right (so we don't need to duplicate code */
+.github-fork-ribbon {
+  /* The right and left lasses determine the side we attach our banner to */
+  position: absolute;
+
+  /* Add a bit of padding to give some substance outside the "stitching" */
+  padding: 2px 0;
+
+  /* Set the base colour */
+  background-color: #a00;
+
+  /* Set a gradient: transparent black at the top to almost-transparent black at the bottom */
+  background-image: -webkit-gradient(linear, left top, left bottom, from(rgba(0, 0, 0, 0.00)), to(rgba(0, 0, 0, 0.15)));
+  background-image: -webkit-linear-gradient(top, rgba(0, 0, 0, 0.00), rgba(0, 0, 0, 0.15));
+  background-image: -moz-linear-gradient(top, rgba(0, 0, 0, 0.00), rgba(0, 0, 0, 0.15));
+  background-image: -o-linear-gradient(top, rgba(0, 0, 0, 0.00), rgba(0, 0, 0, 0.15));
+  background-image: -ms-linear-gradient(top, rgba(0, 0, 0, 0.00), rgba(0, 0, 0, 0.15));
+  background-image: linear-gradient(top, rgba(0, 0, 0, 0.00), rgba(0, 0, 0, 0.15));
+  filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0,StartColorStr='#000000', EndColorStr='#000000');
+
+  /* Add a drop shadow */
+  -webkit-box-shadow: 0px 2px 3px 0px rgba(0, 0, 0, 0.5);
+  box-shadow: 0px 2px 3px 0px rgba(0, 0, 0, 0.5);
+
+  z-index: 9999;
+}
+
+.github-fork-ribbon a {
+  /* Set the font */
+  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
+  font-size: 13px;
+  font-weight: 700;
+  color: white;
+
+  /* Set the text properties */
+  text-decoration: none;
+  text-shadow: 0 -1px rgba(0,0,0,0.5);
+  text-align: center;
+
+  /* Set the geometry. If you fiddle with these you'll also need to tweak the top and right values in #github-fork-ribbon. */
+  width: 200px;
+  line-height: 20px;
+
+  /* Set the layout properties */
+  display: inline-block;
+  padding: 2px 0;
+
+  /* Add "stitching" effect */
+  border-width: 1px 0;
+  border-style: dotted;
+  border-color: rgba(255,255,255,0.7);
+}
+
+.github-fork-ribbon-wrapper {
+  width: 150px;
+  height: 150px;
+  position: absolute;
+  overflow: hidden;
+  top: 0;
+}
+
+.github-fork-ribbon-wrapper.left {
+  left: 0;
+}
+
+.github-fork-ribbon-wrapper.right {
+  right: 0;
+}
+
+.github-fork-ribbon-wrapper.left-bottom {
+  position: fixed;
+  top: inherit;
+  bottom: 0;
+  left: 0;
+}
+
+.github-fork-ribbon-wrapper.right-bottom {
+  position: fixed;
+  top: inherit;
+  bottom: 0;
+  right: 0;
+}
+
+.github-fork-ribbon-wrapper.right .github-fork-ribbon {
+  top: 42px;
+  right: -43px;
+
+  /* Rotate the banner 45 degrees */
+  -webkit-transform: rotate(45deg);
+  -moz-transform: rotate(45deg);
+  -o-transform: rotate(45deg);
+  transform: rotate(45deg);
+}
+
+.github-fork-ribbon-wrapper.left .github-fork-ribbon {
+  top: 42px;
+  left: -43px;
+
+  /* Rotate the banner -45 degrees */
+  -webkit-transform: rotate(-45deg);
+  -moz-transform: rotate(-45deg);
+  -o-transform: rotate(-45deg);
+  transform: rotate(-45deg);
+}
+
+
+.github-fork-ribbon-wrapper.left-bottom .github-fork-ribbon {
+  top: 80px;
+  left: -43px;
+
+  /* Rotate the banner -45 degrees */
+  -webkit-transform: rotate(45deg);
+  -moz-transform: rotate(45deg);
+  -o-transform: rotate(45deg);
+  transform: rotate(45deg);
+}
+
+.github-fork-ribbon-wrapper.right-bottom .github-fork-ribbon {
+  top: 80px;
+  right: -43px;
+
+  /* Rotate the banner -45 degrees */
+  -webkit-transform: rotate(-45deg);
+  -moz-transform: rotate(-45deg);
+  -o-transform: rotate(-45deg);
+  transform: rotate(-45deg);
+}

css/gh-fork-ribbon.ie.css

@@ -0,0 +1,68 @@
+/* IE voodoo courtesy of http://stackoverflow.com/a/4617511/263871 and
+ * http://www.useragentman.com/IETransformsTranslator */
+.github-fork-ribbon-wrapper.right .github-fork-ribbon {
+  /* IE positioning hack (couldn't find a transform-origin alternative for IE) */
+  top: -22px;
+  right: -62px;
+
+  /* IE8+ */
+  -ms-filter: "progid:DXImageTransform.Microsoft.Matrix(M11=0.7071067811865474, M12=-0.7071067811865477, M21=0.7071067811865477, M22=0.7071067811865474, SizingMethod='auto expand')";
+  /* IE6 and 7 */
+  filter: progid:DXImageTransform.Microsoft.Matrix(
+    M11=0.7071067811865474,
+    M12=-0.7071067811865477,
+    M21=0.7071067811865477,
+    M22=0.7071067811865474,
+    SizingMethod='auto expand'
+  );
+}
+
+.github-fork-ribbon-wrapper.left .github-fork-ribbon {
+  top: -22px;
+  left: -22px;
+
+  /* IE8+ */
+  -ms-filter: "progid:DXImageTransform.Microsoft.Matrix(M11=0.7071067811865483, M12=0.7071067811865467, M21=-0.7071067811865467, M22=0.7071067811865483, SizingMethod='auto expand')";
+  /* IE6 and 7 */
+  filter: progid:DXImageTransform.Microsoft.Matrix(
+    M11=0.7071067811865483,
+    M12=0.7071067811865467,
+    M21=-0.7071067811865467,
+    M22=0.7071067811865483,
+    SizingMethod='auto expand'
+  );
+}
+
+.github-fork-ribbon-wrapper.left-bottom .github-fork-ribbon {
+  /* IE positioning hack (couldn't find a transform-origin alternative for IE) */
+  top: 12px;
+  left: -22px;
+
+
+  /* IE8+ */
+  -ms-filter: "progid:DXImageTransform.Microsoft.Matrix(M11=0.7071067811865474, M12=-0.7071067811865477, M21=0.7071067811865477, M22=0.7071067811865474, SizingMethod='auto expand')";
+  /* IE6 and 7 */
+/*  filter: progid:DXImageTransform.Microsoft.Matrix(
+    M11=0.7071067811865474,
+    M12=-0.7071067811865477,
+    M21=0.7071067811865477,
+    M22=0.7071067811865474,
+    SizingMethod='auto expand'
+  );
+*/}
+
+.github-fork-ribbon-wrapper.right-bottom .github-fork-ribbon {
+  top: 12px;
+  right: -62px;
+
+  /* IE8+ */
+  -ms-filter: "progid:DXImageTransform.Microsoft.Matrix(M11=0.7071067811865483, M12=0.7071067811865467, M21=-0.7071067811865467, M22=0.7071067811865483, SizingMethod='auto expand')";
+  /* IE6 and 7 */
+  filter: progid:DXImageTransform.Microsoft.Matrix(
+    M11=0.7071067811865483,
+    M12=0.7071067811865467,
+    M21=-0.7071067811865467,
+    M22=0.7071067811865483,
+    SizingMethod='auto expand'
+  );
+}