/* Popover 样式 */
.popover {
    position: absolute;
    left: 0;
    bottom: 0;
    transform: translate(0, calc(100% + 12px));
    z-index: 1000;
    max-width: 600px;
    padding: 8px 12px;
    background: #fff;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
    font-size: 14px;
    line-height: 1.5;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s, visibility 0.2s;
}

.popover.show {
    opacity: 1;
    visibility: visible;
}

.popover-arrow {
    position: absolute;
    width: 8px;
    height: 8px;
    background: #fff;
    border-top: 1px solid #ddd;
    border-right: 1px solid #ddd;
    transform: rotate(-45deg);
}

.popover-arrow.top {
    bottom: -5px;
    left: 50%;
    margin-left: -4px;
}

.popover-arrow.bottom {
    top: -5px;
    left: 20px;
    margin-left: -4px;
}

.popover-arrow.left {
    right: -5px;
    top: 50%;
    margin-top: -4px;
}

.popover-arrow.right {
    left: -5px;
    top: 50%;
    margin-top: -4px;
}