/* 动态圆圈背景效果 */
.animated-circles-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    z-index: -1;
}

.circle {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.3);
    animation: float 20s infinite ease-in-out;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0) translateX(0) scale(1);
        opacity: 0.2;
    }
    25% {
        transform: translateY(-20px) translateX(10px) scale(1.05);
        opacity: 0.25;
    }
    50% {
        transform: translateY(10px) translateX(-15px) scale(0.95);
        opacity: 0.3;
    }
    75% {
        transform: translateY(-15px) translateX(5px) scale(1.02);
        opacity: 0.22;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .circle {
        animation-duration: 25s;
    }
}

@media (max-width: 480px) {
    .circle {
        animation-duration: 30s;
    }
}