.container {
    padding-left: 10%;
    padding-right: 10%;
}

.center_bar {
    padding-left: 10%;
    padding-right: 10%;
}

@media screen and (max-width: 600px) {
    .container {
        padding-left: 10%;
        padding-right: 10%;
    }

    .center_bar {
        padding-left: 3%;
        padding-right: 3%;
    }
}

/* 默认情况下，图片宽度 */
.img-thumbnail {
    width: 100%;
    max-width: 100%; /* 这一行确保图片不会超出其容器的宽度 */
}

/* 当屏幕尺寸小于600px时 */
@media screen and (max-width: 600px) {
    /* 图片宽度为屏幕宽度的50%，并且居中 */
    .img-thumbnail {
        width: 50%;
        margin: 0 auto; /* 这一行使图片在其容器中居中 */
    }
}

h2 {
    font-size: 2rem;
    font-weight: bold;
    margin-bottom: 1rem;
}

.lead {
    font-size: 1.1rem;
    margin-bottom: 1rem;
}

ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.service-list li::before {
    content: "\25CF"; /* Unicode character for solid circle */
    display: inline-block;
    margin-right: 5px;
    font-size: 12px;
}

footer {
    color: white;
}

nav, footer {
    margin-left: 0;
    margin-right: 0;
    padding-left: 0;
    padding-right: 0;
}

.nav-item.dropdown:hover .dropdown-menu {
    display: block;
}

section {
    padding-top: 2em;
    padding-bottom: 0;
    margin-top: 0;
}

table tr {
    display: flex;
    padding-top: 10px;
}

table tr td:first-child {
    flex: 0 0 30%;
    display: flex;
    align-items: center; /*img vertically aligned*/
}

table tr td:nth-child(2) {
    flex: 1;
    padding-left: 10px;
}

/*!* set img width to whole td width *!*/
table tr td img {
    width: 100%;
    max-width: 100%; /* no overflow */
}

/* when screen width is less than 600px */
@media screen and (max-width: 600px) {
    /* vertically stack td */
    table tr {
        display: block;
    }
    table tr td {
        display: block;
        width: 100%;
    }

    table tr td img {
        width: 60%;
        margin: 0 auto; /* set img center */
    }
}

.icon-button {
    border: none;
    outline: none;
    background-color: transparent;
    cursor: pointer;
    transition: all 0.3s ease-in-out;
}

.icon-button:hover {
    transform: scale(1.1);
}

.icon-button a {
    display: flex;
    justify-content: center;
    align-items: center;
}

.icon-button img {
    margin: 0;
    padding: 0;
    height: 40px;
    width: 40px;
}

.button-group {
    display: flex;
    justify-content: left;
    align-items: center;
    padding-top: 0.2em;
}

@media screen and (max-width: 600px) {
    .button-group {
        justify-content: center;
    }
}

.publication-links {
    display: flex;
    justify-content: flex-start;
    margin-top: 5px;
    margin-bottom: 15px;
}

.publication-links a{
    margin-right: 10px;
}