main.css

body {
    padding-top: 150px;
}

#block {
    margin: 0 auto;
    background-color: #EEEEEE;
    width: 250px;
    height: 100px;
    padding: 10px;
    border-radius: 10px;
}

#triangle {
    margin-left: auto;
    margin-right: auto;
    width: 0; 
    height: 0; 
    border-left: 53px solid transparent;
    border-right: 53px solid transparent;
    border-top: 53px solid #EEEEEE;
}

#txt, #addLine {
    margin: 0 auto;
    text-align: center;
}

#addLine {
    padding-top: 20px;
}

.button_save {
    margin: 0 auto;
    text-align: center;
    padding-top: 5px;
}

input[type="button"] {
    border-radius: 5px;
    color: #fff;
    background-color: #000;
}

#popup {
    position: absolute;
    height: 135px;
    display: none;
}

#txtarea {
    margin: 0 auto;
    height: 50px;
    width: 240px;
    border: 2px solid #765942;
    border-radius: 10px;
    text-align: center;
    resize: none;
    overflow: hidden /* для IE*/
}

table {
    margin: 0 auto;
    border: 2px solid black;
    width: 80%;
    margin-top: 10%;
    border-collapse: collapse;
    text-align: center;
}


td, th {
    border: 2px solid black;
    background-color: #CDD1D4;
}

td {
    background-color: #F8F9FA;
}

td:hover {
    background-color: #F7F2ED;
}