body, html {
    height: 100%;
    margin: 0;
    padding: 0;
    overflow-x: hidden;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background-color: #d1d1d1;
}

iframe {
    display: block;
    width: 100%;
    height: 98vh;
    max-width: 100vw;
    max-height: 100vh;
    border: none;
    margin: auto;
    box-sizing: border-box;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
}

.button-container {
    margin: 10px;
    display: flex;
    justify-content: space-evenly;
    width: 100%;
}

.download-btn {
    vertical-align: middle;
    display: inline-block;
    padding: 12px 24px;
    background-color: #4e4e4e;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    font-size: 16px;
    font-weight: bold;
    text-align: center;
    border: none;
    cursor: pointer;
    transition: background-color 0.3s, box-shadow 0.3s;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.download-btn:hover, .download-btn:focus {
    background-color: #007506;
    text-decoration: none;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
}