/* General Body Style - Light Blue Engineering Notes */
body {
  font-family: Arial, sans-serif;
  background-color: #eaf4ff; /* soft blueprint blue */
  margin: 0;
  padding: 0;
  text-align: center;

  /* Engineering Blueprint Background */
  background-image:
    url('math-bg.png'); /* your new blueprint background PNG */
    
  background-size: 500px auto; /* tile size */
  background-repeat: repeat;
  background-position: center;
}

/* Centered Heading Styles */
h1 {
  color: #333;
  font-size: 3em;
  margin-top: 50px;
  text-shadow: 0 1px 0 #fff;
}

h3 {
  color: black;
  font-size: 1.5em;
  margin-top: 10px;
  font-style: italic;
  text-shadow: 0 1px 0 #fff;
}

h6 {
  color: #555;
  font-size: 0.5em;
  margin-top: 50px;
}

/* Paragraph Style */
div p {
  font-size: 1.2em;
  color: #333;
  margin-top: 20px;
}

/* Adding some space around content */
body > div, body > h1, body > h3 {
  margin-bottom: 20px;
}

/* Materials Section - Loose Leaf Paper Style */
.materials-container {
  display: flex;
  gap: 40px;
  margin-top: 20px;
  flex-wrap: wrap;
  justify-content: center;
  padding: 10px;
}

.material {
  position: relative;
  text-align: center;
  border: 1px solid #e0dfd5;
  padding: 15px 15px 15px 30px;
  border-radius: 10px;
  background-color: rgba(255,255,255,0.9); /* white paper feel */
  box-shadow: 0 3px 6px rgba(0,0,0,0.05);
  max-width: 300px;
  flex: 1 1 250px;
}

/* Punch Hole Effect */
.material::before,
.material::after {
  content: "";
  position: absolute;
  left: 10px;
  width: 8px;
  height: 8px;
  background: #fff;
  border: 1px solid #ccc;
  border-radius: 50%;
  box-shadow: inset 0 1px 2px rgba(0,0,0,0.2);
}

.material::before { top: 15px; }
.material::after { bottom: 15px; }

.material img {
  max-width: 100%;
  height: auto;
  border-radius: 6px;
  margin-bottom: 10px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

/* Link Styles */
a {
  color: #007bff;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* ✅ Responsive Design */
@media (max-width: 768px) {
  .materials-container {
    flex-direction: column;
    align-items: center;
  }

  h1 { font-size: 2em; }
  h3 { font-size: 1.2em; }
  div p { font-size: 1em; }
}