style.css

body {
  margin: 0;
  padding: 0;
  background-color: #f9f9f9;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -ms-flex-line-pack: center;
  align-content: center;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  min-height: 100vh;
  -ms-flex-wrap: wrap;
  flex-wrap: wrap;
  font-family: 'Raleway';
}

.payment-title {
  width: 100%;
  text-align: center;
}

.form-container .field-container:first-of-type {
  grid-area: name;
}

.form-container .field-container:nth-of-type(2) {
  grid-area: number;
}

.form-container .field-container:nth-of-type(3) {
  grid-area: expiration;
}

.form-container .field-container:nth-of-type(4) {
  grid-area: security;
}

.field-container input {
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}

.field-container {
  position: relative;
}

.form-container {
  display: grid;
  grid-column-gap: 10px;
  grid-template-columns: auto auto;
  grid-template-rows: 90px 90px 90px;
  grid-template-areas: "name name""number number""expiration security";
  max-width: 400px;
  padding: 20px;
  color: #707070;
}

label {
  padding-bottom: 5px;
  font-size: 13px;
}

input {
  margin-top: 3px;
  padding: 15px;
  font-size: 16px;
  width: 100%;
  border-radius: 3px;
  border: 1px solid #dcdcdc;
}

.ccicon {
  height: 36px;
  position: absolute;
  right: 6px;
  top: calc(50% - 17px);
  width: 58px;
}

.container {
  width: 100%;
  max-width: 400px;
  max-height: 251px;
  height: 54vw;
  padding: 20px;
}

#ccsingle {
  position: absolute;
  right: 15px;
  top: 20px;
}

#ccsingle svg {
  width: 100px;
  max-height: 60px;
}

.creditcard svg#cardfront,
.creditcard svg#cardback {
  width: 100%;
  -webkit-box-shadow: 1px 5px 6px 0px black;
  box-shadow: 1px 5px 6px 0px black;
  border-radius: 22px;
}

#generatecard {
  cursor: pointer;
  float: right;
  font-size: 12px;
  color: #fff;
  padding: 2px 4px;
  background-color: #909090;
  border-radius: 4px;
  cursor: pointer;
  float: right;
}

/* CHANGEABLE CARD ELEMENTS */
.creditcard .lightcolor,
.creditcard .darkcolor {
  -webkit-transition: fill .5s;
  transition: fill .5s;
}

.creditcard .lightblue {
  fill: #03A9F4;
}

.creditcard .lightbluedark {
  fill: #0288D1;
}

.creditcard .red {
  fill: #ef5350;
}

.creditcard .reddark {
  fill: #d32f2f;
}

.creditcard .purple {
  fill: #ab47bc;
}

.creditcard .purpledark {
  fill: #7b1fa2;
}

.creditcard .cyan {
  fill: #26c6da;
}

.creditcard .cyandark {
  fill: #0097a7;
}

.creditcard .green {
  fill: #66bb6a;
}

.creditcard .greendark {
  fill: #388e3c;
}

.creditcard .lime {
  fill: #d4e157;
}

.creditcard .limedark {
  fill: #afb42b;
}

.creditcard .yellow {
  fill: #ffeb3b;
}

.creditcard .yellowdark {
  fill: #f9a825;
}

.creditcard .orange {
  fill: #ff9800;
}

.creditcard .orangedark {
  fill: #ef6c00;
}

.creditcard .grey {
  fill: #bdbdbd;
}

.creditcard .greydark {
  fill: #616161;
}

/* FRONT OF CARD */
#svgname {
  text-transform: uppercase;
}

#cardfront .st2 {
  fill: #FFFFFF;
}

#cardfront .st3 {
  font-family: 'Source Code Pro', monospace;
  font-weight: 600;
}

#cardfront .st4 {
  font-size: 54.7817px;
}

#cardfront .st5 {
  font-family: 'Source Code Pro', monospace;
  font-weight: 400;
}

#cardfront .st6 {
  font-size: 33.1112px;
}

#cardfront .st7 {
  opacity: 0.6;
  fill: #FFFFFF;
}

#cardfront .st8 {
  font-size: 24px;
}

#cardfront .st9 {
  font-size: 36.5498px;
}

#cardfront .st10 {
  font-family: 'Source Code Pro', monospace;
  font-weight: 300;
}

#cardfront .st11 {
  font-size: 16.1716px;
}

#cardfront .st12 {
  fill: #4C4C4C;
}

/* BACK OF CARD */
#cardback .st0 {
  fill: none;
  stroke: #0F0F0F;
  stroke-miterlimit: 10;
}

#cardback .st2 {
  fill: #111111;
}

#cardback .st3 {
  fill: #F2F2F2;
}

#cardback .st4 {
  fill: #D8D2DB;
}

#cardback .st5 {
  fill: #C4C4C4;
}

#cardback .st6 {
  font-family: 'Source Code Pro', monospace;
  font-weight: 400;
}

#cardback .st7 {
  font-size: 27px;
}

#cardback .st8 {
  opacity: 0.6;
}

#cardback .st9 {
  fill: #FFFFFF;
}

#cardback .st10 {
  font-size: 24px;
}

#cardback .st11 {
  fill: #EAEAEA;
}

#cardback .st12 {
  font-family: 'Pacifico', cursive;
}

#cardback .st13 {
  font-size: 37.769px;
}

/* FLIP ANIMATION */
.container {
  perspective: 1000px;
}

.creditcard {
  width: 100%;
  max-width: 400px;
  -webkit-transform-style: preserve-3d;
  transform-style: preserve-3d;
  transition: -webkit-transform 0.6s;
  -webkit-transition: -webkit-transform 0.6s;
  transition: transform 0.6s;
  transition: transform 0.6s, -webkit-transform 0.6s;
  cursor: pointer;
}

.creditcard .front,
.creditcard .back {
  position: absolute;
  width: 100%;
  max-width: 400px;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  -webkit-font-smoothing: antialiased;
  color: #47525d;
}

.creditcard .back {
  -webkit-transform: rotateY(180deg);
  transform: rotateY(180deg);
}

.creditcard.flipped {
  -webkit-transform: rotateY(180deg);
  transform: rotateY(180deg);
}


/* validate block */

.validate-wrapper {
  width: 100%;
  padding: 20px;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
}

.validate-button-wrapper {
  width: 100%;
  text-align: center;
}

#validate-button {
  padding: 12px 50px;
  background-color: #616161;
  border-radius: 7px;
  font-size: 23px;
  color: white;
  border: 0;
  transition: background-color 0.3s;
  margin-bottom: 20px;
}

#validate-button:hover {
  background-color: #7c7c7c;
}

#validate-button:active {
  background-color: #505050;
}

.validate-result {
  opacity: 0;
  padding: 10px 100px;
  width: 100%;
  max-width: 650px;
  text-align: center;
  color: white;
  border-radius: 10px;
  transition: background-color 0.5s;
}