Add CSS layer docs

doc/guides/csslayer/NormalizeDoc.vue

@@ -0,0 +1,23 @@
+<template>
+    <DocSectionText v-bind="$attrs">
+        <p>Normalize is another utility to reset CSS of the standard elements. While importing the CSS file, assign it to a layer and define the layer order with primevue coming after the normalized layer.</p>
+        <DocSectionCode :code="code" />
+    </DocSectionText>
+</template>
+
+<script>
+export default {
+    data() {
+        return {
+            checked: false,
+            code: {
+                basic: `
+@layer normalize, primevue;
+
+@import "normalize.css" layer(normalize-reset);
+`
+            }
+        };
+    }
+};
+</script>