Fix failing tests.

docs/examples/styles/margin.css

@@ -7,4 +7,5 @@ Label {
     margin: 4 8;
     background: blue 20%;
     border: blue wide;
+    width: 100%;
 }

docs/examples/styles/outline.css

@@ -2,8 +2,10 @@ Screen {
     background: white;
     color: black;
 }
+
 Label {
     margin: 4 8;
     background: green 20%;
     outline: wide green;
+    width: 100%;
 }

docs/examples/styles/padding.css

@@ -6,4 +6,5 @@ Screen {
 Label {
     padding: 4 8;
     background: blue 20%;
+    width: 100%;
 }