body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0 20px;
  background-color: #f4f4f9;
  color: #333;
}

header {
  text-align: center;
  padding: 20px 0;
  background-color: #4a90e2;
  color: white;
  margin-bottom: 20px;
}

h1, h2 {
  margin: 0 0 10px 0;
}

section {
  background: white;
  padding: 15px 20px;
  margin-bottom: 20px;
  border-radius: 8px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

#calendar {
  display: flex;
  justify-content: space-between;
}

.day {
  flex: 1;
  border: 1px solid #ddd;
  margin: 0 5px;
  padding: 10px;
  border-radius: 5px;
  background-color: #e9f0fb;
  text-align: center;
}

#timer-display {
  font-size: 2em;
  text-align: center;
  margin-bottom: 10px;
}

button {
  background-color: #4a90e2;
  color: white;
  border: none;
  padding: 10px 15px;
  margin: 0 5px 5px 0;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1em;
}

button:disabled {
  background-color: #a0a0a0;
  cursor: not-allowed;
}

blockquote {
  font-style: italic;
  color: #555;
  border-left: 4px solid #4a90e2;
  padding-left: 10px;
  margin: 10px 0;
}