气泡对话框


			.arrow_box {
			position: relative;
			background: #88b7d5;
			border: 4px solid #c2e1f5;
			}
			.arrow_box:after, .arrow_box:before {
			bottom: 100%;
			left: 50%;
			border: solid transparent;
			content: " ";
			height: 0;
			width: 0;
			position: absolute;
			pointer-events: none;
			}

			.arrow_box:after {
			border-color: rgba(136, 183, 213, 0);
			border-bottom-color: #88b7d5;
			border-width: 30px;
			margin-left: -30px;
			}
			.arrow_box:before {
			border-color: rgba(194, 225, 245, 0);
			border-bottom-color: #c2e1f5;
			border-width: 36px;
			margin-left: -36px;
			}