Magic Card

1<script lang="ts">
2	import { motion, useMotionTemplate, useMotionValue } from "motion-sv";
3	import { cn } from "$UTILS$";
4	import type { Snippet } from "svelte";
5 
6	interface MagicCardProps {
7		/** Card content */
8		children?: Snippet;
9		/** Additional CSS classes */
10		class?: string;
11		/** Size of the gradient circle */
12		gradientSize?: number;
13		/** Color of the gradient overlay */
14		gradientColor?: string;
15		/** Opacity of the gradient overlay */
16		gradientOpacity?: number;
17		/** Starting color of the border gradient */
18		gradientFrom?: string;
19		/** Ending color of the border gradient */
20		gradientTo?: string;
21	}
22 
23	let {
24		children,
25		class: className,
26		gradientSize = 200,
27		gradientColor = "#262626",
28		gradientOpacity = 0.8,
29		gradientFrom = "#9E7AFF",
30		gradientTo = "#FE8BBB",
31	}: MagicCardProps = $props();
32 
33	let mouseX = $derived(useMotionValue(-gradientSize));
34	let mouseY = $derived(useMotionValue(-gradientSize));
35 
36	let borderGradient = $derived(
37		useMotionTemplate`radial-gradient(${gradientSize}px circle at ${mouseX}px ${mouseY}px, ${gradientFrom}, ${gradientTo}, var(--border) 100%)`
38	);
39	let overlayGradient = $derived(
40		useMotionTemplate`radial-gradient(${gradientSize}px circle at ${mouseX}px ${mouseY}px, ${gradientColor}, transparent 100%)`
41	);
42 
43	const reset = () => {
44		mouseX.set(-gradientSize);
45		mouseY.set(-gradientSize);
46	};
47 
48	const handlePointerMove = (e: PointerEvent) => {
49		const target = e.currentTarget as HTMLElement;
50		const rect = target.getBoundingClientRect();
51		mouseX.set(e.clientX - rect.left);
52		mouseY.set(e.clientY - rect.top);
53	};
54 
55	// Reset on mount
56	$effect(() => {
57		reset();
58	});
59 
60	// Global event listeners
61	$effect(() => {
62		const handleGlobalPointerOut = (e: PointerEvent) => {
63			if (!e.relatedTarget) {
64				reset();
65			}
66		};
67 
68		const handleVisibility = () => {
69			if (document.visibilityState !== "visible") {
70				reset();
71			}
72		};
73 
74		window.addEventListener("pointerout", handleGlobalPointerOut);
75		window.addEventListener("blur", reset);
76		document.addEventListener("visibilitychange", handleVisibility);
77 
78		return () => {
79			window.removeEventListener("pointerout", handleGlobalPointerOut);
80			window.removeEventListener("blur", reset);
81			document.removeEventListener("visibilitychange", handleVisibility);
82		};
83	});
84</script>
85 
86<div
87	class={cn("group relative rounded-[inherit]", className)}
88	onpointermove={handlePointerMove}
89	onpointerleave={reset}
90	onpointerenter={reset}
91	role="region"
92>
93	<motion.div
94// … truncated