Here's a simple square using HTML and CSS:
Basic square:
<div style="width: 100px; height: 100px; background-color: #3498db;"></div>With CSS class:
.square {
width: 100px;
height: 100px;
background-color: #e74c3c;
}Styled square:
.square {
width: 150px;
height: 150px;
background-color: #2ecc71;
border: 2px solid #27ae60;
border-radius: 8px;
box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}The key is making sure the width and height are equal to create a perfect square.
Here's a big box using HTML and CSS:
Basic big box:
<div style="width: 400px; height: 300px; background-color: #3498db;"></div>Really big box:
.big-box {
width: 500px;
height: 400px;
background-color: #e74c3c;
border: 3px solid #c0392b;
}Responsive big box (takes up most of the screen):
.big-box {
width: 80vw; /* 80% of viewport width */
height: 60vh; /* 60% of viewport height */
background-color: #9b59b6;
}Just increase the width and height values to make the box as big as you need!