/* Font Loading Fallback Styles - 字体加载回退样式 */

/* 字体加载状态类 */
.font-loading {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, 
                 "Helvetica Neue", Arial, sans-serif;
}

.font-loaded {
    font-family: "Roboto", -apple-system, BlinkMacSystemFont, "Segoe UI", 
                 "Helvetica Neue", Arial, sans-serif;
}

/* FontAwesome 回退 */
.font-loading .fa:before {
    font-family: Arial, sans-serif;
    content: "•";
    color: #666;
}

.font-loaded .fa:before {
    font-family: FontAwesome, "Font Awesome 5 Free", Arial, sans-serif;
}

/* 防止字体闪烁的过渡效果 */
.fa {
    transition: font-family 0.1s ease-in-out;
}

/* Web字体加载时的性能优化 */
@supports (font-display: swap) {
    .fa {
        font-display: swap;
    }
}

/* 预加载关键字体的CSS */
.preload-fonts {
    position: absolute;
    left: -9999px;
    top: -9999px;
    font-family: FontAwesome;
    font-size: 1px;
    opacity: 0;
    pointer-events: none;
}