/* Header styles */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 10;
  background-color: rgba(17, 17, 17, 0.85);
  backdrop-filter: blur(5px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  transform: translateY(0);
  will-change: transform;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.logo-container {
  display: flex;
  align-items: center;
}

.logo {
  height: auto;
  width: 80px;
  opacity: 0.8;
  transition: opacity 0.3s ease;
}

.logo:hover {
  opacity: 1;
}

.nav-links {
  display: flex;
  gap: 20px;
  align-items: center;
}

.nav-link {
  color: rgba(255, 255, 255, 0.3);
  text-decoration: none;
  font-size: 16px;
  font-family: "JuliaMono", monospace;
  font-weight: 900;
  transition: color 0.3s ease, background-color 0.3s ease;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px 12px;
  border-radius: 4px;
}

.nav-link:hover {
  color: white;
  background-color: rgba(255, 255, 255, 0.1);
}

.difficulty-toggle,
.sound-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 110px;
  position: relative;
  overflow: hidden;
} 