Add ability to specify custom shadow names.

Sources/Slipstream/TailwindCSS/Effects/View+shadow.swift

@@ -19,6 +19,27 @@ extension View {
     return modifier(TailwindClassModifier(add: Set(classNames), condition: condition))
   }
 
+  /// Sets the shadow of the view to a specific name.
+  ///
+  /// To use custom colors, add them to your tailwind.config.js `theme.extend.colors` property:
+  ///
+  /// ```js
+  /// theme: {
+  ///   extend: {
+  ///     boxShadow: {
+  ///       'puck': '0 0 4px 0 #0003,0 2px 0 0 #0000001a'
+  ///     },
+  ///   }
+  /// }
+  /// ```
+  ///
+  /// - SeeAlso: Tailwind CSS' [box shadow](https://tailwindcss.com/docs/box-shadow) documentation.
+  /// - SeeAlso: Tailwind CSS' [box shadow color](https://tailwindcss.com/docs/box-shadow-color) documentation.
+  @available(iOS 17.0, macOS 14.0, *)
+  public func shadow(_ shadow: String, condition: Condition? = nil) -> some View {
+    return modifier(TailwindClassModifier(add: "shadow-" + shadow, condition: condition))
+  }
+
   /// Maps a shadow radius to the closest Tailwind CSS shadow class.
   ///
   /// - Parameter radius: The radius in points to be mapped.

Tests/SlipstreamTests/TailwindCSS/Effects/ShadowTests.swift

@@ -21,4 +21,8 @@ struct ShadowTests {
     try #expect(renderHTML(Div {}.shadow(radius: 10)) == #"<div class="shadow-md"></div>"#)
     try #expect(renderHTML(Div {}.shadow(radius: 100)) == #"<div class="shadow-2xl"></div>"#)
   }
+
+  @Test func customName() throws {
+    try #expect(renderHTML(Div {}.shadow("puck")) == #"<div class="shadow-puck"></div>"#)
+  }
 }