add css-in-js post

site/content/blog/2018-12-26-svelte-css-in-js.md

@@ -0,0 +1,29 @@
+---
+title: Using CSS-in-JS with Svelte
+description: You don't need to, but you can
+pubdate: 2018-12-26
+author: Rich Harris
+authorURL: https://twitter.com/Rich_Harris
+---
+
+CSS is a core part of any web app. By extension, a UI framework that doesn't have a built-in way to add styles to your components is unfinished.
+
+That's why Svelte allows you to add CSS in a component's `<style>` tag. Co-locating your CSS with your markup means we can [solve the biggest problems developers face when writing CSS](/blog/the-zen-of-just-writing-css) without introducing new ones, all while providing a rather nice development experience.
+
+But Svelte's style handling does have some limitations. It's too difficult to share styles between components, or apply app-level optimisations. These are areas we plan to address in future versions, but in the meantime if you need those things you can use any framework-agnostic CSS-in-JS library.
+
+
+## For example
+
+Here, we're using [Aphrodite](https://github.com/Khan/aphrodite) to generate scoped class names that can be used across multiple components:
+
+<iframe
+	title="Aphrodite example"
+	src="/repl/embed?gist=01345cf1c2c9ec0dfd617c2e2adb7bf7"
+	scrolling="no"
+></iframe>
+
+It's important to note that most CSS-in-JS libraries have a runtime library, and many don't support statically extracting styles out into a separate <code>.css</code> file at build time (which is essential for the best performance). You should therefore only use CSS-in-JS if it's necessary for your application!
+
+Note that you can mix-and-match — you can still use Svelte's built-in CSS handling alongside a CSS-in-JS library.
+

site/src/routes/blog/[slug].html

@@ -82,4 +82,25 @@
 		color: var(--second);
 		z-index: 2;
 	}
+
+	.post :global(iframe) {
+		width: 100%;
+		height: 420px;
+		margin: 2em 0;
+		border-radius: var(--border-r);
+		border: 0.8rem solid var(--second);
+	}
+
+	@media (min-width: 910px) {
+		.post :global(iframe) {
+			width: calc(100vw - 2 * var(--side-nav));
+			margin: 2em calc(400px + var(--side-nav) - 50vw);
+		}
+	}
+
+	@media (min-height: 800px) {
+		.post :global(iframe) {
+			height: 640px;
+		}
+	}
 </style>