style.css

html {
  box-sizing: border-box;
  font-family: karla;
  font-size: 16px;
}

*, *:before, *:after {
  box-sizing: inherit;
}

h2, h4, p {
  margin: 0;
}

body {
  background-color: #e5eff5;
  margin: 0px;
  padding: 20px;
}

#card {
  background-color: white;
  width: 625px;
  height: 480px;
  border-radius: 7px;
  /*overflow: hidden. See line 50 for more info*/
  box-shadow: 2px 3px 7px 0px rgba(0,0,0,0.35);
}

#top-section {
  width: 100%;/*To make it fill up the entire width of its parent container*/
  height: 45%;
  padding: 35px;
  color: rgb(152, 166, 189)
}

#bottom-section {
  width: 100%;
  height: 55%;
}

#bottom-left-section {
  display: inline-block; /*Inline does not respect height and width elements so thiis is whu=y we must use the inline block property value*/ 
  width: 50%;
  height: 100%;
  vertical-align: top; /*Another quirk of css. This property only applies when the display is in inline-block mode. This will be used t align the two div elements*/
  background-color: rgba(42, 178, 176);
  color: rgb(229, 239, 245);
  border-bottom-left-radius: 7px;
  /* OR We can also set the overflow property to hidden in the #card css rule to ensure that anything that trespasses the borders if the card will not show*/
  padding: 35px;
}

#bottom-right-section {
  display: inline-block; /*remember to rmemove any whitespace between the two div on the same line (Just a css quirk)*/
  width: 50%;
  height: 100%;
  vertical-align: top;
  background-color: rgba(42, 178, 176, 0.88);
  color: rgb(229, 239, 245);
  border-bottom-right-radius: 7px;
  padding: 35px;
}

button {
  background-color: #c0df34;
  text-align: left;
  border: none;
  margin-top: 25px;
  width: 100%;
  height: 25%;
  border-radius: 5px;
  text-align: center;
  color: rgb(229, 239, 245);
  box-shadow: 20px 11px 60px -10px rgba(0,0,0,0.75);
  font-weight: 700
}

#sub-price-1, #sub-price-2 {
  display: inline-block;
  margin-bottom: 10px;
  vertical-align: middle;
  /*Or we can set the position property to fixed and manipulate the top, left, buttom, or right properties afterwards*/
  padding-top: 10px
}

#sub-price-2{
  padding-left: 6px;
}

ul {
  font-size: 0.92rem;
  margin-top: 30px;
  list-style: none;
  padding: 0px;
}

li {
  padding-top: 2px
}

#top-section p{
  line-height: 1.6rem
}

button:hover {
  cursor: pointer;
  background-color: rgba(192, 223, 52, 0.9);
  /* Or opacity: 0.9;*/
  transform: scale(1.02)
}

#paragraph-1 {
  margin-top: 15px
}