:root {
    --primary: #6366f1;
    --accent: #a855f7;
    --bg: #0f172a;
}

body {
    background: radial-gradient(circle at center, #1e1b4b 0%, #0f172a 100%);
    color: white;
    height: 100vh;
    margin: 0;
    overflow: hidden;
    font-family: 'PingFang TC', 'Microsoft JhengHei', sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

/* 3D Scene Container */
.scene {
    width: 320px;
    height: 420px;
    perspective: 1200px;
    cursor: pointer;
    z-index: 10;
}

.card {
    width: 100%;
    height: 100%;
    position: relative;
    transition: transform 0.8s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    transform-style: preserve-3d;
}

.card.is-flipped {
    transform: rotateY(180deg) rotateZ(2deg);
}

/* Card Faces */
.card-face {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border-radius: 24px;
    padding: 2rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    border: 2px solid rgba(255, 255, 255, 0.1);
}

.card-front {
    background: linear-gradient(135deg, #4338ca 0%, #6d28d9 100%);
    background-image: url("https://www.transparenttextures.com/patterns/carbon-fibre.png");
}

.card-back {
    background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
    transform: rotateY(180deg);
    border: 2px solid var(--primary);
}

/* Decorative Elements */
.glow {
    position: absolute;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 50% 50%, rgba(99, 102, 241, 0.15) 0%, transparent 70%);
    pointer-events: none;
}

.floating-particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
}

.particle {
    position: absolute;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    animation: float linear infinite;
}

@keyframes float {
    0% { transform: translateY(100vh) scale(0); opacity: 0; }
    50% { opacity: 0.5; }
    100% { transform: translateY(-100px) scale(1.2); opacity: 0; }
}

@keyframes burst {
    0% { transform: translate(-50%, -50%) scale(1); opacity: 1; }
    100% { transform: translate(calc(-50% + var(--tx)), calc(-50% + var(--ty))) scale(0); opacity: 0; }
}

.text-glow {
    text-shadow: 0 0 15px rgba(255, 255, 255, 0.5);
}

/* Button Custom UI */
.btn-fancy {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s ease;
}

.btn-fancy:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.quote-container {
    font-size: 1.5rem;
    line-height: 1.6;
    font-weight: 700;
    text-align: center;
}

.stamp {
    position: absolute;
    bottom: 20px;
    right: 20px;
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.3);
    text-transform: uppercase;
    letter-spacing: 2px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 4px 8px;
    border-radius: 4px;
    transform: rotate(-15deg);
}