/* 共享样式 */
:root {
    --bg-gradient: linear-gradient(135deg, rgba(142, 197, 252, 0.7), rgba(224, 195, 252, 0.7), rgba(251, 194, 235, 0.7));
    --primary-gradient: linear-gradient(90deg, #ff6ec7, #6a5af9);
    --purple-shadow: rgba(106, 90, 249, 0.5);
}

html {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
}

body {
    margin: 0;
    padding: 0;
    font-family: "Segoe UI", "PingFang SC", sans-serif;
    background: var(--bg-gradient), url('bg.jpg') center/cover no-repeat fixed;
    background-attachment: fixed;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.back-button {
    position: fixed;
    top: 20px;
    left: 20px;
    padding: 12px 24px;
    background: rgba(255, 255, 255, 0.25);
    backdrop-filter: blur(10px);
    border: none;
    border-radius: 12px;
    color: white;
    font-size: 1rem;
    cursor: pointer;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    transition: all 0.3s ease;
    z-index: 1000;
}

.back-button:hover {
    background: rgba(255, 255, 255, 0.35);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.2);
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(16px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes pulse {

    0%,
    100% {
        opacity: 0.6;
    }

    50% {
        opacity: 1;
    }
}

/* 响应式设计 - 平板设备 (768px 及以上) */
@media (max-width: 768px) {
    .back-button {
        top: 15px;
        left: 15px;
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}

/* 响应式设计 - 手机设备 (480px 及以下) */
@media (max-width: 480px) {
    body {
        background-attachment: scroll;
    }

    .back-button {
        top: 10px;
        left: 10px;
        padding: 8px 16px;
        font-size: 0.8rem;
    }
}