このコンポーネントの実TSXです。未ログインのままでも、購入前に読めます。

src/components/ui/magnetic-cta-button.tsx

"use client";

import * as React from "react";
import { ArrowRight } from "lucide-react";
import { coerceDisplayText } from "@/generation/lib/coerceActionNodes";
import { cn } from "@/lib/utils";

export type MagneticCtaButtonProps = Omit<
  React.ComponentPropsWithoutRef<"button">,
  "type"
> & {
  href?: string;
  type?: "button" | "submit" | "reset";
};

const STYLE_ID = "magnetic-cta-button-css";
const MCTB_CSS = `
@keyframes mctb-orbit {
  to { transform: translate(-50%, -50%) rotate(360deg); }
}
@keyframes mctb-liquid-drift {
  0% { transform: translate(-8%, -6%) rotate(0deg) scale(1.05); }
  50% { transform: translate(6%, 8%) rotate(18deg) scale(1.12); }
  100% { transform: translate(-8%, -6%) rotate(0deg) scale(1.05); }
}
.mctb-spin,
.mctb-spin-glow {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 190%;
  height: 190%;
  transform: translate(-50%, -50%);
  pointer-events: none;
  background: conic-gradient(
    from 0deg,
    transparent 0deg,
    transparent 14deg,
    #4ec4ff 28deg,
    #6b4dff 38deg,
    #ff4d9a 50deg,
    #ffd056 62deg,
    transparent 80deg,
    transparent 194deg,
    #62d4ff 210deg,
    #8a63ff 222deg,
    #ff5aa8 236deg,
    #ffe08a 248deg,
    transparent 266deg,
    transparent 360deg
  );
  animation: mctb-orbit 3.8s linear infinite;
}
.mctb-spin-glow {
  width: 220%;
  height: 220%;
  filter: blur(8px) saturate(1.45);
  opacity: 0.5;
}
.mctb-glass {
  position: relative;
  display: flex;
  overflow: hidden;
  border-radius: 9999px;
  padding: 9px;
  font-weight: 400;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.45);
  backdrop-filter: blur(18px) saturate(180%) contrast(1.08);
  -webkit-backdrop-filter: blur(18px) saturate(180%) contrast(1.08);
  box-shadow:
    0 10px 28px rgba(15, 15, 20, 0.12),
    inset 1.5px 1.5px 0 rgba(255, 255, 255, 0.65),
    inset -1px -1px 0 rgba(255, 255, 255, 0.12),
    inset 0 -10px 16px rgba(15, 15, 20, 0.06);
}
.mctb-liquid {
  position: absolute;
  inset: -55%;
  pointer-events: none;
  background:
    radial-gradient(ellipse 42% 34% at 22% 12%, rgba(255,255,255,0.7) 0%, transparent 58%),
    radial-gradient(ellipse 38% 42% at 78% 86%, rgba(120, 190, 255, 0.22) 0%, transparent 55%),
    radial-gradient(ellipse 28% 30% at 68% 18%, rgba(255,255,255,0.35) 0%, transparent 50%),
    radial-gradient(ellipse 50% 40% at 40% 70%, rgba(255, 160, 220, 0.1) 0%, transparent 60%);
  animation: mctb-liquid-drift 10s ease-in-out infinite;
  mix-blend-mode: screen;
  opacity: 0.85;
}
@media (prefers-reduced-motion: reduce) {
  .mctb-spin,
  .mctb-spin-glow,
  .mctb-liquid {
    animation: none;
  }
}
`;

function ensureStyles() {
  if (typeof document === "undefined") return;
  let style = document.getElementById(STYLE_ID) as HTMLStyleElement | null;
  if (!style) {
    style = document.createElement("style");
    style.id = STYLE_ID;
    document.head.appendChild(style);
  }
  if (style.textContent !== MCTB_CSS) style.textContent = MCTB_CSS;
}

export const MagneticCtaButton = React.forwardRef<
  HTMLButtonElement,
  MagneticCtaButtonProps
>(
  (
    {
      href,
      className,
      children,
      style,
      type = "button",
      onPointerLeave,
      onPointerMove,
      ...props
    },
    ref,
  ) => {
    const filterId = `mctb-liquid-${React.useId().replace(/:/g, "")}`;

    React.useEffect(() => {
      ensureStyles();
    }, []);

    const label = coerceDisplayText(children) ?? "Get started";
    const face = (
      <>
        <span className="pl-[14px] pr-2 text-[17px] font-medium tracking-[-0.02em] text-zinc-600">
          {label}
        </span>
        <span
          aria-hidden
          className="relative isolate flex size-[36px] shrink-0 overflow-hidden rounded-full p-[1.6px]"
        >
          <span className="mctb-spin-glow" />
          <span className="mctb-spin" />
          <span className="relative z-10 flex size-full items-center justify-center rounded-full bg-white">
            <ArrowRight className="size-[18px] text-zinc-700" />
          </span>
        </span>
      </>
    );

    const innerClass = cn(
      "relative isolate inline-flex h-[36px] cursor-pointer items-center rounded-full bg-transparent pr-0 no-underline",
      "focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-zinc-300 focus-visible:ring-offset-2",
      "disabled:pointer-events-none disabled:opacity-50",
      className,
    );

    const control = href ? (
      <a
        href={href}
        data-tsuna-id="magnetic-cta-button"
        className={innerClass}
        style={style}
      >
        {face}
      </a>
    ) : (
      <button
        ref={ref}
        type={type}
        data-tsuna-id="magnetic-cta-button"
        className={innerClass}
        style={style}
        onPointerMove={onPointerMove}
        onPointerLeave={onPointerLeave}
        {...props}
      >
        {face}
      </button>
    );

    return (
      <span className="relative inline-flex">
        <svg
          className="pointer-events-none absolute h-px w-px overflow-visible opacity-0"
          aria-hidden
        >
          <defs>
            <filter
              id={filterId}
              x="-40%"
              y="-40%"
              width="180%"
              height="180%"
              colorInterpolationFilters="sRGB"
            >
              <feTurbulence
                type="fractalNoise"
                baseFrequency="0.018 0.04"
                numOctaves="2"
                seed="4"
                result="noise"
              />
              <feDisplacementMap
                in="SourceGraphic"
                in2="noise"
                scale="28"
                xChannelSelector="R"
                yChannelSelector="G"
              />
            </filter>
          </defs>
        </svg>
        <div className="mctb-glass">
          <div className="pointer-events-none absolute inset-0 z-0 overflow-hidden rounded-[inherit]">
            <div
              className="mctb-liquid"
              style={{ filter: `url(#${filterId})` }}
            />
          </div>
          <div className="relative z-10 flex items-center">{control}</div>
        </div>
      </span>
    );
  },
);

MagneticCtaButton.displayName = "MagneticCtaButton";