:root {
    --primary-color: #E53935;
    --secondary-color: #FFC107;
    --text-color: #333333;
    --background-color: #F5F5F5;
    --container-width: 90vw;
    --container-height: calc(var(--container-width) * 0.75); /* Maintain a 4:3 aspect ratio */
}

/************************不需要改*****************************/
body {
    font-family: 'Noto Sans SC', sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--background-color);
    color: var(--text-color);
}
header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    text-align: center;
    padding: 1rem 0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}
nav ul {
    display: flex;
    justify-content: center;
    list-style-type: none;
    padding: 0;
    margin-top: 0.1rem;
}
nav ul li {
    margin: 0 1rem;
}
nav ul li a {
    text-decoration: none;
    color: white;
    font-weight: bold;
    transition: color 0.3s ease;
    font-size: 1.5rem;
}
nav ul li a:hover {
    color: var(--secondary-color);
}
.text-content a {
    color: inherit; /* 继承父元素的颜色 */
    text-decoration: none; /* 去掉下划线 */
}
.text-content a:hover {
    text-decoration: underline; /* 鼠标悬停时显示下划线 */
}
/************************不需要改*****************************/
#home {
    height: 95vh;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 0rem;
}
/* 就是这个容器影响边距  */
.container {
    position: relative;
    width: var(--container-width);
    height: var(--container-height);
    background: #f5f5f5;
    box-shadow: 0 calc(var(--container-width) * 0.02) calc(var(--container-width) * 0.02) #dbdbdb;
    overflow: hidden; 
    top: -24%;  /*改这个 调整上下边距*/
    /* top:calc(var(--container-height) * -0.28); */
}


.container .slide .item {
    width: 20%;
    height: 50%;
    position: absolute;
    top: 50%;
    transform: translate(0, -50%);
    border-radius: calc(var(--container-width) * 0.02);
    box-shadow: 0 calc(var(--container-width) * 0.03) calc(var(--container-width) * 0.03) #505050;
    background-position: 50% 50%;
    background-size: cover;
    display: inline-block;
    transition: 0.5s;
    
}

.slide .item:nth-child(1),
.slide .item:nth-child(2) {
    top: 0;
    left: 0;
    transform: translate(0, 0);
    border-radius: 0;
    width: 100%;
    height: 100%;
}

.slide .item:nth-child(3) {
    left: 50%;
}

.slide .item:nth-child(4) {
    left: calc(50% + var(--container-width) * 0.22);
}

.slide .item:nth-child(5) {
    left: calc(50% + var(--container-width) * 0.44);
}

.slide .item:nth-child(n+6) {
    left: calc(50% + var(--container-width) * 0.66);
    opacity: 0;
}

.item .content {
    position: absolute;
    top: 50%;
    left: calc(var(--container-width) * 0.1);
    width: calc(var(--container-width) * 0.3);
    text-align: left;
    color: #eee;
    transform: translate(0, -50%);
    font-family: system-ui;
    display: none;
    
}

.slide .item:nth-child(2) .content {
    display: block;
}

.content .name {
    font-size: calc(var(--container-width) * 0.07);
    text-transform: uppercase;
    font-weight: bold;
    opacity: 0;
    animation: animate 1s ease-in-out 1 forwards;
    white-space: nowrap;
}

.content .des {
    font-size: calc(var(--container-width) * 0.03);
    width: calc(var(--container-width) * 0.3);
    margin-top: calc(var(--container-width) * 0.01);
    margin-bottom: calc(var(--container-width) * 0.02);
    opacity: 0;
    animation: animate 1s ease-in-out 0.3s 1 forwards;
    white-space: normal;
    word-wrap: break-word;
}

.content button {
    padding: calc(var(--container-width) * 0.01) calc(var(--container-width) * 0.02);
    border: none;
    cursor: pointer;
    opacity: 0;
    animation: animate 1s ease-in-out 0.6s 1 forwards;
    font-size: calc(var(--container-width) * 0.026);
}

@keyframes animate {
    from {
        opacity: 0;
        transform: translate(0, calc(var(--container-width) * 0.1));
        filter: blur(calc(var(--container-width) * 0.033));
    }
    to {
        opacity: 1;
        transform: translate(0);
        filter: blur(0);
    }
}

.button {
    width: 100%;
    text-align: center;
    position: absolute;
    bottom: calc(var(--container-width) * 0.02);
}

.button button {
    width: calc(var(--container-width) * 0.04);
    height: calc(var(--container-width) * 0.035);
    border-radius: calc(var(--container-width) * 0.008);
    border: none;
    cursor: pointer;
    margin: 0 calc(var(--container-width) * 0.005);
    border: 1px solid #000;
    transition: 0.3s;
}

.button button:hover {
    background: #ababab;
    color: #fff;
}

/***************************************************************************************/
.gallery-container {
    max-width: 1200px;
    margin: -22rem auto;   /*改这个 调整上下边距*/
    padding: 0 1rem;
    /* position: relative; */
}

.research-item {
    display: flex;
    margin-bottom: 4rem;
    background-color: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
    
}

.research-item:hover {
    transform: translateY(-5px);
}

.image-container {
    flex: 1;
    position: relative;

}

.image-container img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    
}

.image-caption {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 0.5rem;
    margin: 0;
    text-align: center;
    font-size: 0.9rem;
}

.text-content {
    flex: 1;
    padding: 2rem;
}

h3 {
    color: var(--primary-color);
    margin-top: 0;
}

.back-button {
    position: fixed;
    bottom: 2rem;
    left: 2rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s ease;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.back-button:hover {
    background-color: #C62828;
}

@media (max-width: 768px) {
    .research-item {
        flex-direction: flex-direction;   /* 图片文字左右排列就改为column*/
    }

    .image-container, .text-content {
        flex: 50%;                        /* 图片和文字的占比 */
    }

    .image-container img {
        height: 250px;
    }
    
}