/* ========== General Page Layout ========== */
body {
  font-family: Georgia, 'Times New Roman', Times, serif;
  margin: 0;
  padding: 0;
  margin-top: 70px;
  background-color: #f4f4f4;
  color: #333;
  box-sizing: border-box;
}

.layout {
  display: flex;
  margin: auto;
  line-height: 1.6;
}

/* ========== Sidebar ========== */
.sidebar {
  width: 250px;
  background: #f4f4f4;
  padding: 20px;
  border: 1px solid #ddd;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  margin-right: 20px;
}

.sidebar h2 {
  font-size: 20px;
  margin-top: 25px;
  margin-bottom: 10px;
}

.sidebar ul {
  list-style: none;
  padding: 0;
}

.sidebar ul li {
  margin: 10px 0;
}

.sidebar ul li a {
  color: #333;
  text-decoration: none;
  transition: color 0.3s ease;
}

.sidebar ul li a:hover {
  color: #6c5ce7;
}

/* ========== Main Content ========== */
.content {
  margin-left: 100px;
  margin-right: 100px;
  margin-top: 50px;
  margin-bottom: 50px;
  padding: 20px;
  flex: 1;
  background: #f4f4f4;
}

.content h1 {
  font-size: 20px;
  margin-bottom: 20px;
  text-align: center;
  color: #6c5ce7;
}


/* ========== Hidden Elements ========== */
.hidden {
  display: none;
}

/* ========== Buttons ========== */
button {
  margin: 0;
  padding: 8px 16px;
  border: 1px solid #ccc;
  border-radius: 5px;
  cursor: pointer;
  font-size: 14px;
  transition: background-color 0.3s ease;
}

button:hover {
  color: #3e2dc4;
  border-color: #3e2dc4;
}

/* ========== Exercise Cards ========== */
.exercise,
.exercise1 {
  background-color: #ffffff;
  border: 1px solid #e0e0e0;
  border-left: 5px solid #6c5ce7;
  border-radius: 8px;
  padding: 20px;
  margin: 25px 0;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.04);
  transition: box-shadow 0.3s ease;
}

.exercise:hover,
.exercise1:hover {
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.08);
}

.exercise p,
.exercise1 p {
  font-size: 18px;
  font-weight: 500;
  margin-bottom: 10px;
  color: #333;
}


/* code block */
pre code {
    color: black;
    background: #f4f4f4;
    font-family: Consolas, monospace;
    padding: 10px;
    display: block;
    overflow-x: auto;
}

pre.solution {
    border: 1px solid #ddd;
    padding: 10px;
    background-color: #f9f9f9;
    border-radius: 5px;
    font-family: 'Courier New', Courier, monospace;
    position: relative;
    overflow: auto;
}

.solution code {
    white-space: pre;
    display: block;
    counter-reset: line-number;
}

.line-number {
    display: inline-block;
    width: 2em;
    margin-right: 1em;
    text-align: right;
    color: #999;
}

pre.solution code span {
    display: inline-block;
}
  

.exercise1 {
    margin-top: 60px;
}