:root {
	--bg: #ffffff;
	--surface: #ffffff;
	--text: #111111;
	--accent: #39ff14;
	--border: #111111;
}

* {
	box-sizing: border-box;
}

body {
	margin: 0;
	min-height: 100vh;
	font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
	background: var(--bg);
	color: var(--text);
}

.page {
	min-height: 100vh;
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;
	padding: 1.5rem;
}

.card-container {
	width: 100%;
	max-width: 500px;
	display: flex;
	flex-direction: column;
	align-items: center;
	gap: 3rem;
	perspective: 1200px;
}

.card-viewport {
	width: 100%;
	height: 600px;
	position: relative;
	perspective: 1200px;
}

.card {
	width: 100%;
	height: 100%;
	border: 2px solid var(--border);
	background: var(--surface);
	position: absolute;
	top: 0;
	left: 0;
	box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
	display: flex;
	flex-direction: column;
	transform-origin: center bottom;
	transition: none;
}

.card-content {
	padding: 2rem;
	height: 100%;
	overflow-y: auto;
	display: flex;
	flex-direction: column;
}

.card.card-exit-up {
	animation: cardFlyUp 0.6s ease-in forwards;
}

.card.card-enter-from-bottom {
	animation: cardFlyIn 0.6s ease-out forwards;
}

@keyframes cardFlyUp {
	0% {
		transform: translateY(0) rotateX(0deg);
		opacity: 1;
	}
	100% {
		transform: translateY(-800px) rotateX(15deg);
		opacity: 0;
	}
}

@keyframes cardFlyIn {
	0% {
		transform: translateY(800px) rotateX(-15deg);
		opacity: 0;
	}
	100% {
		transform: translateY(0) rotateX(0deg);
		opacity: 1;
	}
}

h1 {
	margin: 0 0 0.5rem 0;
	font-size: 1.6rem;
}

.subtitle {
	margin: 0 0 1.2rem 0;
	font-size: 0.95rem;
	color: var(--text);
}

form {
	display: grid;
	gap: 0.6rem;
	border: 2px solid var(--border);
	padding: 1rem;
	margin-bottom: 1rem;
}

label {
	font-weight: 600;
	font-size: 0.95rem;
}

input {
	width: 100%;
	border: 2px solid var(--border);
	padding: 0.75rem 0.85rem;
	font-size: 1rem;
	color: var(--text);
	background: #ffffff;
}

#Frage {
	margin-bottom: 1rem;
	font-weight: 600;
	background: #ffffff;
}

input:focus {
	outline: 3px solid var(--accent);
	outline-offset: 1px;
}

button {
	margin-top: 0.2rem;
	border: 2px solid var(--border);
	background: var(--accent);
	color: var(--text);
	padding: 0.85rem 1rem;
	font-size: 1rem;
	font-weight: 700;
	cursor: pointer;
	transition: filter 0.2s;
}

button:hover {
	filter: brightness(0.95);
}

button:active {
	transform: translateY(1px);
}

#cardData {
	margin-top: 1rem;
	padding: 0.9rem;
	font-size: 0.9rem;
	line-height: 1.45;
	min-height: 2rem;
}

/* Card Stack */
.card-stack {
	position: relative;
	width: 200px;
	height: 100px;
	cursor: pointer;
}

.stack-card {
	position: absolute;
	width: 100%;
	height: 80px;
	border: 2px solid var(--border);
	background: var(--surface);
	box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
	transform-origin: center;
	transition: transform 0.3s ease;
}

.stack-card-1 {
	top: 0;
	left: 0;
	transform: translateY(0) rotateZ(-2deg);
}

.stack-card-2 {
	top: 8px;
	left: 8px;
	transform: translateY(0) rotateZ(1deg);
	z-index: -1;
}

.stack-card-3 {
	top: 16px;
	left: 16px;
	transform: translateY(0) rotateZ(-1.5deg);
	z-index: -2;
}

.card-stack:hover .stack-card-1 {
	transform: translateY(-8px) rotateZ(-2deg);
}

.card-stack:hover .stack-card-2 {
	transform: translateY(-4px) rotateZ(1deg);
}