body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: linear-gradient(135deg, #e0f7fa 0%, #80deea 100%);
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.main-heading-container {
  background: white;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.main-heading {
  color: #ff7300;
  margin: 0;
  font-size: 1.5rem;
}

.group-logo {
  border-radius: 50%;
  width: 50px;
  display: block;
}

.about-link {
  text-decoration: none;
  color: #666;
  font-weight: 600;
}

.content-wrapper {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
}

.buttons-heading-container {
  background: white;
  padding: 3rem;
  border-radius: 20px;
  box-shadow: 0 15px 35px rgba(0,0,0,0.1);
  text-align: center;
  width: 320px;
}

.difficulty-heading {
  margin-bottom: 2rem;
  color: #2d3436;
  font-size: 1.25rem;
}

.button {
  width: 100%;
  padding: 1rem;
  margin-bottom: 1rem;
  border: none;
  border-radius: 10px;
  color: white;
  font-weight: bold;
  font-size: 1rem;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
}

.button:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(0,0,0,0.15);
}

.button1 { background-color: #27ae60; }
.button2 { background-color: #f1c40f; color: #333; }
.button3 { background-color: #e74c3c; margin-bottom: 0; }