* {
  font-family: Arial;
}

body {
  background-color: ffffff;
}

.title {
  max-width: 960px;
  font-weight: bold;
  margin: 10px 0;
  text-align: center;
}

.main-container {
  display: flex;
  background-color: #ffffff;
  max-width: 960px;
}

.card-container {
  width: 750px;
  display: flex;
  flex-flow: row wrap;
  background-color: #efefef;
}

.card {
  display: flex;
  height: 150px;
  flex: 1 0 30%;
  justify-content: center;
  align-items: center;
  color: white;
  font-size: 80px;
}

#card1 {
  background-color: #6f98a8;
}
#card2 {
  background-color: #2b8ead;
}
#card3 {
  background-color: #2f454e;
}
#card4 {
  background-color: #2b8ead;
}
#card5 {
  background-color: #2f454e;
}
#card6 {
  background-color: #bfbfbf;
}
#card7 {
  background-color: #bfbfbf;
}
#card8 {
  background-color: #6f98a8;
}
#card9 {
  background-color: #2f454e;
}

.button-container {
  background-color: #efefef;
  flex: 1 0 30%;
}

button {
  background-color: #72c3dc;
  color: white;
  cursor: pointer;
  display: block;
  width: 60%;
  padding: 8px;
  margin: 0 auto;
  border-radius: 10px;
  margin-top: 20px;
  border: none;
  outline: none;
  box-shadow: 0 5px #2b8ead;
}

button:hover {
  background-color: #2b8ead;
}

button:active {
  background-color: #2b8ead;
  box-shadow: 0 3px #2f454e;
  transform: translateY(4px);
}

.footer-container {
  background-color: #efefef;
  max-width: 960px;
  padding: 15px 0 50px 0;
  text-align: center;
}

@media screen and (max-width: 375px) {
  /* For mobile: */
  body {
    background-color: #000000;
    border-radius: 10px;
  }

  .title {
    text-align: center;
    margin: 20px 0;
    font-weight: bold;
    background-color: black;
    color: white;
    font-size: 25px;
  }

  .main-container {
    display: flex;
    flex-direction: column-reverse;
  }

  .card-container {
    width: 100%;
    background-color: #ffffff;
    margin: 5 auto;
  }

  .card {
    flex: 1 0 60%;
    height: 50px;
    margin: 5px 10px 5px 10px;
    font-size: 20px;
    font-weight: bold;
    color: #000000;
  }

  .button-container {
    background-color: #ffffff;
    margin: 0 auto;
  }

  button {
    background-color: #72c3dc;
    margin: 10px -5px 10px 5px;
    display: inline;
    width: 90px;
    height: 55px;
    border: none;
    outline: none;
    box-shadow: 0 5px#2b8ead;
  }

  button:hover {
    background-color: #2b8ead;
  }

  button:active {
    background-color: #2b8ead;
    box-shadow: 0 3px #2f454e;
    transform: translateY(4px);
  }

  #card1 {
    background-color: #efefef;
    border-left: 8px solid #6f98a8;
  }
  #card2 {
    background-color: #efefef;
    border-left: 8px solid #2b8ead;
  }
  #card3 {
    background-color: #efefef;
    border-left: 8px solid #2f454e;
  }
  #card4 {
    background-color: #efefef;
    border-left: 8px solid #2b8ead;
  }
  #card5 {
    background-color: #efefef;
    border-left: 8px solid #2f454e;
  }
  #card6 {
    background-color: #efefef;
    border-left: 8px solid #bfbfbf;
  }
  #card7 {
    background-color: #efefef;
    border-left: 8px solid #bfbfbf;
  }
  #card8 {
    background-color: #efefef;
    border-left: 8px solid #6f98a8;
  }
  #card9 {
    background-color: #efefef;
    border-left: 8px solid #2f454e;
  }

  .footer-container {
    background-color: #ffffff;
    padding: 15px 0 50px 0;
    text-align: center;
  }
}