/* ----------------------------------------
   1. VARIABLES & RESET
---------------------------------------- */
:root {
  /* Primary palette (Blues) */
  --primary:         #29b6f6;
  --primary-light:   #81d4fa;
  --primary-lighter: #b3e5fc;
  --primary-dark:    #0288d1;

  /* Shadows & transitions */
  --shadow-light:    0 2px 6px rgba(0, 0, 0, 0.1);
  --shadow-medium:   0 4px 10px rgba(0, 0, 0, 0.15);
  --transition:      0.25s ease-in-out;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Comic Neue', 'Comic Sans MS', cursive, sans-serif;
  background: var(--primary-lighter);
  color: #333;
  line-height: 1.6;
  user-select: none;
}

/* Utility: Hidden for screen readers */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ----------------------------------------
   2. HEADER / NAV
---------------------------------------- */
header {
  position: sticky;
  top: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background: var(--primary);
  box-shadow: var(--shadow-medium);
  z-index: 100;
}

.logo {
  font-size: 1.8rem;
  font-weight: bold;
  color: #fff;
}

nav ul {
  list-style: none;
  display: flex;
}

nav a {
  font-size: 1rem;
  margin-left: 1rem;
  padding: 0.4rem 0.8rem;
  color: #fff;
  text-decoration: none;
  border-radius: 0.4rem;
  transition: background var(--transition), transform var(--transition);
}

nav a:hover,
nav a:focus {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
  outline: none;
}

/* ----------------------------------------
   3. INFO (SCORE & INSTRUCTIONS)
---------------------------------------- */
#info {
  text-align: center;
  padding: 1.5rem 1rem;
  margin-bottom: 1rem;
}

#score {
  font-size: 2.8rem;
  font-weight: bold;
  text-shadow: 1px 1px 2px rgba(0,0,0,0.2);
  margin-bottom: 0.5rem;
}

.score-value {
  color: var(--primary-dark);
}

#instructions {
  font-size: 1.4rem;
  font-style: italic;
}

/* ----------------------------------------
   4. GAME CONTAINER & CANVAS
---------------------------------------- */
#game-container {
  width: 90%;
  max-width: 800px;
  margin: 0 auto 2rem;
  padding: 0.5rem;
  background: var(--primary-light);
  border: 4px solid var(--primary-dark);
  border-radius: 1rem;
  box-shadow: var(--shadow-medium), inset 0 0 15px rgba(0,0,0,0.05);
  overflow: hidden;
}

#gameCanvas {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 0.8rem;
  box-shadow: inset 0 0 20px rgba(0,0,0,0.1);
}

/* ----------------------------------------
   5. FOOTER
---------------------------------------- */
footer {
  text-align: center;
  padding: 1rem 2rem;
  background: var(--primary);
  color: #fff;
  font-size: 0.9rem;
  box-shadow: var(--shadow-light) inset 0 1px 3px rgba(0,0,0,0.1);
}

/* ----------------------------------------
   6. RESPONSIVE ADJUSTMENTS
---------------------------------------- */
@media (max-width: 600px) {
  header {
    flex-direction: column;
    align-items: flex-start;
  }

  nav a {
    margin: 0.5rem 0 0 0;
  }

  #score {
    font-size: 2.4rem;
  }

  #instructions {
    font-size: 1.2rem;
  }
}