.banner {
    position: relative;
    width: 100%;
    height: 24%;
    background: url('../img/banner1.jpg') center/cover no-repeat;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 50px;
    box-sizing: border-box;
    color: white;
    overflow: hidden;
}

.banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.2);
}

.banner h1, .banner p, .banner .button {
    position: relative;
    z-index: 1;
}

.banner h1 {
    margin: 10px 0;
    font-size: 2em;
}

.banner p {
    margin: 10px 0;
    font-size: 1em;
}

.banner .button {
    margin: 10px 0;
    padding: 10px 40px;
    background-color: white;
    color: #4a6cf7;
    text-decoration: none;
    border-radius: 38px;
    transition: background-color 0.3s, color 0.3s;
}

.banner .button:hover {
    background-color: #3a5ccd;
    color: rgb(255, 232, 232);
}
.description {
    color: rgb(187, 191, 255);
    text-decoration: none;
    font-style: italic;
}
.container {
    flex: 1;
    display: flex;
    flex-direction: column;
    max-width: 1200px;
    margin: 20px auto;
    padding: 20px;
    border-radius: 8px;
}

.main-content {
    flex: 1;
    padding-left: 10%;
    max-width: 100%;
}

.toc {
    position: fixed;
    top: 47%;
    left: 40px;
    width: 180px;
    padding: 20px;
    background-color: #f5f5f5;
    border-radius: 8px;
}

.toc ul {
    list-style: none;
    padding: 0;
}

.toc li {
    margin: 10px 0;
}

.toc a {
    text-decoration: none;
    color: black;
    transition: color 0.3s;
}

.toc a:hover {
    color: #4a6cf7;
}

h2 {
    color: #333;
    margin: 22px 0 10px;
    padding-bottom: 5px;
}

p {
    text-indent: 2em;
    margin-bottom: 15px;
    line-height: 1.8em;
}
@media (max-width: 768px) {
    .nav a {
        float: none;
        display: block;
        text-align: left;
    }
    .logo img {
        float: none;
        display: block;
        margin: 0 auto;
    }
    .banner {
        height: auto;
        padding: 20px;
    }
    .banner h1 {
        font-size: 1.5em;
    }
    .banner p {
        font-size: 1em;
    }
    .banner .button {
        padding: 10px 20px;
    }
    .container {
        flex-direction: column;
        padding: 10px;
    }
    .main-content {
        padding-left: 0;
    }
    .toc {
        position: relative;
        top: auto;
        left: auto;
        width: auto;
        margin-bottom: 20px;
    }
}