.gallery {
	display: flex;
    justify-content: center;
    align-items: center;
    margin:auto;
}
.gallery_item {
	display: flex;
    justify-content: center;
    align-items: center;
	font-size: 1.5em;
	padding: 5px;
    margin:  5px;              /* 外側の余白 */
    border-radius:  5px;        /* 角丸指定 */
    width: 80%;                 /* 幅指定 */

    text-align: center;
    background: #a6c8f7;
}
.gallery h3{
	font-size: 1.8em;
	text-align: center;
}

@media screen and (max-width: 768px) {
	.gallery {
   		width: 100%;
    	flex-direction: column; 
	}
	.gallery_item {
    width: 90%;                 /* 幅指定 */
	}
	h2 {
		padding-top:50px;
	}
}