3Dに傾く透過カードのCSSジェネレーター

<div class="card-perspective">
	<div class="glass-card">
		<div class="reflection"></div>
		<div class="content">
			<span class="card-title">3D Glass Card</span>
			<p>Mouse over me to see the 3D tilt and reflection effect.</p>
			<button>Learn More</button>
		</div>
	</div>
</div>

.card-perspective {
	perspective: 1000px;
	width: 320px;
	height: 400px;
}

.glass-card {
	width: 100%;
	height: 100%;
	background: {{card_color}}3a; /* 透明度あり */
	backdrop-filter: blur({{glass_blur}}px);
	-webkit-backdrop-filter: blur({{glass_blur}}px);
	border: 1px solid rgba(255, 255, 255, 0.2);
	border-radius: 24px;
	position: relative;
	transition: transform 0.5s ease-out, box-shadow 0.1s ease;
	transform-style: preserve-3d;
	display: flex;
	align-items: center;
	justify-content: center;
	box-shadow: 0 25px 50px rgba(0, 0, 0, {{shadow_opacity}});
	overflow: hidden;
}

.reflection {
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
	background: linear-gradient(
		135deg,
		rgba(255, 255, 255, 0.4) 0%,
		rgba(255, 255, 255, 0) 60%
	);
	pointer-events: none;
	opacity: 0;
	transition: opacity 0.3s ease;
}

.content {
	padding: 40px;
	text-align: center;
	transform: translateZ(50px); /* 少し浮き上がらせる */
}

.content .card-title {
	display: block;
	color: {{text_color}};
	margin-bottom: 15px;
	font-size: 24px;
	font-weight: bold;
}

.content p {
	color: {{text_color}};
	opacity: 0.8;
	font-size: 14px;
	line-height: 1.6;
}

.content button {
	margin-top: 30px;
	background: {{text_color}};
	color: #000;
	border: none;
	padding: 10px 25px;
	border-radius: 50px;
	font-weight: bold;
	cursor: pointer;
}

const card = document.querySelector('.glass-card');
const reflection = document.querySelector('.reflection');
const maxTilt = {{tilt_max}};

card.addEventListener('mousemove', (e) => {
	const rect = card.getBoundingClientRect();
	const x = e.clientX - rect.left;
	const y = e.clientY - rect.top;
	
	const centerX = rect.width / 2;
	const centerY = rect.height / 2;
	
	const rotateX = ((y - centerY) / centerY) * -maxTilt;
	const rotateY = ((x - centerX) / centerX) * maxTilt;

	// 移動中はレスポンスを良くするため transition を短くする
	card.style.transition = 'transform 0.1s ease-out';
	card.style.transform = `rotateX(${rotateX}deg) rotateY(${rotateY}deg)`;
	
	// 反射光の制御
	reflection.style.opacity = '1';
	reflection.style.background = `radial-gradient(
		circle at ${x}px ${y}px,
		rgba(255, 255, 255, 0.3) 0%,
		rgba(255, 255, 255, 0) 70%
	)`;
});

card.addEventListener('mouseleave', () => {
	// 離れた時はスムーズに戻るよう transition を長くする
	card.style.transition = 'transform 0.6s cubic-bezier(0.23, 1, 0.32, 1)';
	card.style.transform = 'rotateX(0deg) rotateY(0deg)';
	reflection.style.opacity = '0';
});