* {
  margin: 0;
  padding: 0;
  -webkit-box-sizing: border-box;
          box-sizing: border-box;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

:root {
  --times: 16;
}

body {
  display: -ms-grid;
  display: grid;
  place-items: center;
  width: 100%;
  height: 100vh;
}

.sketch-options {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: space-evenly;
      -ms-flex-pack: space-evenly;
          justify-content: space-evenly;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  margin-bottom: 20px;
  background: gray;
  padding: 15px 10px;
}
.sketch-options p {
  font-size: 14px;
  font-weight: bold;
}
.sketch-options button {
  padding: 10px 8px;
  background: black;
  color: white;
  cursor: pointer;
  border: 0;
}
.sketch-options input[type=color] {
  height: 35px;
  width: 80px;
}

.sketch-container {
  width: 500px;
  height: 500px;
  background: #b9b9b9;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -ms-flex-wrap: wrap;
      flex-wrap: wrap;
}
.sketch-container div {
  width: calc(100% / var(--times));
  height: calc(100% / var(--times));
  margin: 0;
  padding: 0;
}