style.css

body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

h1 {
    text-align: center;
    margin-top: 50px;
}

form {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 5px;
    box-shadow: 0px 0px 10px #ccc;
}

h2 {
    margin-top: 20px;
}

label {
    display: block;
    margin-bottom: 10px;
}

input[type="checkbox"] {
    margin-right: 10px;
}

.address-field {
    display: none;
    flex-direction: row;
    margin-bottom: 20px;
}

.address-field label {
    flex: 1;
    text-align: right;
    margin-right: 10px;
}

.address-field input {
    flex: 3;
    padding: 5px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

.address-field button {
    display: none;
}

.address-field img {
    flex: 1;
    margin-left: 10px;
}

#code-box {
    max-width: 800px;
    margin: 20px auto;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 5px;
    box-shadow: 0px 0px 10px #ccc;
    white-space: pre;
    font-family: monospace;
}

textarea {
	width: 83%;
	height: 120px;
	border: 3px solid #cccccc;
	padding: 5px;
	font-family: Tahoma, sans-serif;
	background-image: url(bg.gif);
	background-position: bottom right;
	background-repeat: no-repeat;
}

#copy-btn {
    margin-top: 10px;
}

.crypto-field {
    display: flex;
    flex-direction: row;
    margin-bottom: 10px;
}

.crypto-field label {
    flex: 1;
}

.crypto-field input {
    flex: 3;
    padding: 5px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

.crypto-field img {
    flex: 1;
    margin-left: 10px;
}

.menu_button {
    background-color: navy;
    border: none;
    color: #7df9ff;
    text-align: center;
    font-size: 20px;
    padding: 20px;
    width: 200px;
    transition: all .5s;
    cursor: pointer;
    margin: 5px;
    border-radius: 30px;
    display: block;
    margin-left: auto;
    margin-right: auto;
    margin-top: 30px;
    margin-bottom: 30px;
}

.menu_button span {
    cursor: pointer;
    display: inline-block;
    position: relative;
    transition: .5s
}

.menu_button span:after {
    content: '\00bb';
    position: absolute;
    opacity: 0;
    top: 0;
    right: -1%;
    transition: .5s
}

.menu_button:hover span {
    padding-right: 25px
}

.menu_button:hover span:after {
    opacity: 1;
    right: 0
}

.normal_button {
    border-radius: 30px;
    background-color: navy;
    border: none;
    color: #7df9ff;
    text-align: center;
    font-size: 20px;
    padding: 20px;
    width: 200px;
    transition: all .5s;
    cursor: pointer;
    margin: 5px
}

.normal_button span {
    cursor: pointer;
    display: inline-block;
    position: relative;
    transition: .5s
}

.normal_button span:after {
    content: '\00bb';
    position: absolute;
    opacity: 0;
    top: 0;
    right: -1%;
    transition: .5s
}

.normal_button:hover span {
    padding-right: 25px
}

.normal_button:hover span:after {
    opacity: 1;
    right: 0
}

.normal_button strong {
    color: #fff
}