body {
    background: url('images/beijing.png') no-repeat center center fixed;
    background-size: cover;
    margin: 0;
    font-family: Arial, sans-serif;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 20px;
    background-color: rgba(255, 255, 255, 0.8);
    border-bottom: 2px solid rgb(184, 184, 184);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.logo {
    height: 50px;
}

nav {
    flex-grow: 1;
    display: flex;
    justify-content: center;
}

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

nav li {
    margin: 0 25px;
}

nav a {
    text-decoration: none;
    color: #333;
    font-size: 18px;
    font-weight: bold;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    transition: color 0.3s ease;
}

nav a:hover {
    color: #007BFF;
}

main {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 100px 20px 20px 20px; /* Add top padding to avoid overlap with fixed header */
}

.intro-image {
    width: calc(100% - 1cm); /* Leave 1 cm space on each side */
    border-radius: 10px;
    margin-bottom: 60px;
}

.content-box {
    width: calc(100% - 1cm); /* Leave 1 cm space on each side */
    background-color: white;
    margin: 40px 0;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    text-align: center;
    font-size: 20px;
}

.title-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.title {
    font-size: 24px;
    color: black;
    font-weight: bold;
}

.more a {
    font-size: 16px;
    color: #007BFF;
    text-decoration: none;
}

.more a:hover {
    text-decoration: underline;
}

.button-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 10px;
}

button {
    padding: 10px;
    font-size: 16px;
    border: none;
    border-radius: 5px;
    background-color: #dbe1ff;
    color: rgb(0, 0, 0);
    cursor: pointer;
    transition: background-color 0.3s ease;
}

button:hover {
    background-color: #577dfc;
}

.tab-container {
    display: flex;
}

.tabs {
    display: flex;
    flex-direction: column;
    margin-right: 20px;
}

.tablink {
    background-color: #ffffff;
    border: none;
    outline: none;
    cursor: pointer;
    padding: 14px 16px;
    transition: background-color 0.3s ease;
    font-size: 17px;
    margin-bottom: 10px;
    width: 100px;
}

.tablink:hover {
    background-color: #c0cfff;
}

.tablink.active {
    background-color: #a7b7ff;
}

.tabcontent-container {
    flex-grow: 1;
}

.tabcontent {
    display: none;
}

.tabcontent .button-grid {
    margin-bottom: 20px;
}