body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

header {
    background: #333;
    color: #fff;
    padding: 20px 0;
    text-align: center;
}

header h1 {
    margin: 0;
}
header h3 {
    margin: 0;
    color: #fff;
}

.navbar-nav {
    justify-content: center;
}

.navbar-nav .nav-item .nav-link {
    color: #fff;
    padding: 10px 15px;
}

.container {
    max-width: 1140px;
    margin: 20px auto;
    padding: 0 15px;
}

h2 {
    color: #333;
    margin-bottom: 20px;
}

.speaker, .organizer {
    display: flex;
    align-items: flex-start;
    margin-bottom: 20px;
}

.speaker img, .organizer img {
    border-radius: 50%;
    margin-right: 20px;
    max-width: 150px;
    height: auto;
    flex-shrink: 0;
}

.speaker-info, .organizer-info {
    max-width: calc(100% - 170px);
}

.speaker-info h3, .organizer-info h3 {
    margin-top: 0;
    margin-bottom: 5px;
}

.speaker-info p, .organizer-info p {
    margin: 5px 0;
}

footer {
    background: #333;
    color: #fff;
    text-align: center;
    padding: 10px 0;
    margin-top: 20px;
}

@media (max-width: 767px) {
    .speaker, .organizer {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .speaker img, .organizer img {
        margin: 0 0 10px 0;
    }

    .speaker-info, .organizer-info {
        max-width: 100%;
    }
}

#goToTopBtn {
    display: none; /* Hidden by default */
    position: fixed; /* Fixed/sticky position */
    bottom: 20px; /* Place the button at the bottom of the page */
    right: 30px; /* Place the button 30px from the right */
    z-index: 99; /* Make sure it does not overlap */
    font-size: 18px; /* Increase font size */
    border: none; /* Remove borders */
    outline: none; /* Remove outline */
    background-color: #555; /* Set a background color */
    color: white; /* Text color */
    cursor: pointer; /* Add a mouse pointer on hover */
    padding: 15px; /* Some padding */
    border-radius: 4px; /* Rounded corners */
}

#goToTopBtn:hover {
    background-color: #333; /* Add a dark-grey background on hover */
}