/* 加载动画容器 */
.loading-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(255, 255, 255, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.loading-container::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: inherit;
    opacity: 0.9;
    backdrop-filter: blur(10px);
}

.loading-container.active {
    opacity: 1;
    visibility: visible;
}

/* 加载动画 */
.loading-spinner {
    width: 120px;
    height: 120px;
    background: url('../logo.png') center/contain no-repeat;
    animation: spin 3s ease-in-out infinite;
    filter: drop-shadow(0 0 12px rgba(0, 0, 0, 0.3));
    position: relative;
    z-index: 1;
}

/* 按钮加载状态 */
.btn-loading {
    position: relative;
    color: transparent !important;
}

.btn-loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 24px;
    height: 24px;
    margin-top: -12px;
    margin-left: -12px;
    background: url('../logo.png') center/contain no-repeat;
    animation: spin 3s ease-in-out infinite;
}

/* 加载动画关键帧 */
@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

/* 页面加载效果 */
.page-transition {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.page-transition.loaded {
    opacity: 1;
    transform: translateY(0);
}

/* 分段加载效果 */
.fade-in-section {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-section.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* 延迟加载序列 */
.delay-100 { transition-delay: 0.1s; }
.delay-200 { transition-delay: 0.2s; }
.delay-300 { transition-delay: 0.3s; }
.delay-400 { transition-delay: 0.4s; }
.delay-500 { transition-delay: 0.5s; }