.container {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    min-height: 100vh;
}
.container-fluid {
        height: 100vh;
        display: flex;
        align-items: center;
        justify-content: center;
    }

.d-flex {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}
#btn {
    background-color: #8d918f;
    color: #ffffff;
    transition: background-color 0.4s ease, box-shadow 0.25s ease, transform 0.25s ease;
    cursor: pointer;
    border-radius: 30px;
    transform: translateY(0);
}

#btn:hover,
#btn:focus {
    background-color: #212e27;
    transform: translateY(-6px);
}

#btn:active {
    transform: translateY(2px);
}