html, body {
    height: 100%;
    overflow: auto; /* important ! */
  }
	
	body {
      font-family: Arial, sans-serif;
      background-color: #f1f1f1;
      margin: 0;
      padding: 20px;
    }

    h1 {
      text-align: center;
    }

    .progress-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
      gap: 10px;
      margin-top: 30px;
    }

    .letter-card {
      display: block;
      text-decoration: none;
      color: inherit;
      background-color: white;
      border: 2px solid #ccc;
      border-radius: 10px;
      padding: 15px;
      text-align: center;
      font-size: 1.2em;
      box-shadow: 2px 2px 8px rgba(0,0,0,0.1);
      cursor: pointer;
      transition: box-shadow 0.3s ease;
    }

    .letter-card:hover {
      box-shadow: 4px 4px 12px rgba(0,0,0,0.2);
    }

    .letter-card.completed {
      opacity: 0.5;
      pointer-events: none;
      cursor: not-allowed;
    }

    .level-badge {
      display: inline-block;
      background-color: #2196F3;
      color: white;
      padding: 4px 10px;
      margin-top: 8px;
      border-radius: 12px;
      font-size: 0.9em;
    }

.level-0 { background-color: #e0f3f8; color: #000; }
.level-1 { background-color: #abd9e9; color: #000; }
.level-2 { background-color: #74add1; color: #000; }
.level-3 { background-color: #4575b4; color: #fff; }
.level-4 { background-color: #984ea3; color: #fff; }
.level-5 { background-color: #e41a1c; color: #fff; }
.level-6 { background-color: #ff7f00; color: #000; }
.level-7 { background-color: #ffbf00; color: #000; }
.level-8 { background-color: #a50f15; color: #fff; }

    .filter {
      text-align: center;
      margin-top: 10px;
    }



    section h2 {
      margin-bottom: 0.5em;
      font-size: 1.5em;
      border-bottom: 2px solid #ccc;
      padding-bottom: 0.2em;
    }

    /* Ajout pour mise en valeur de la progression */
	.progress-summary {
	  background-color: #ffffff;
	  border: 1px solid #ddd;
	  padding: 1em;
	  border-radius: 10px;
	  text-align: center;
	  margin-bottom: 10px;
	  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
	}

    .progress-summary p {
      margin: 8px 0;
      font-size: 1em;
    }

    progress {
      width: 100%;
      height: 20px;
      margin-top: 10px;
    }
	
	.progress-actions {
	  display: flex;
	  justify-content: center;
	  gap: 15px;
	  margin: 10px auto 20px auto;
	}

	.progress-actions button {
	  padding: 8px 14px;
	  font-size: 1em;
	  background-color: #4caf50;
	  color: white;
	  border: none;
	  border-radius: 20px;
	  cursor: pointer;
	  transition: transform 0.2s ease, background-color 0.3s ease;
	}

	.progress-actions button:hover {
	  background-color: #388e3c;
	  transform: scale(1.05);
	}
	
	
	.share-box {
	  margin-top: 20px;
	  padding: 15px;
	  background-color: #fefefe;
	  border: 1px solid #ccc;
	  border-radius: 10px;
	  text-align: center;
	  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
	}

	.share-box p {
	  font-size: 1em;
	  margin-bottom: 10px;
	}

	.share-box button {
	  margin: 5px;
	  padding: 8px 12px;
	  font-size: 0.9em;
	  border: none;
	  border-radius: 6px;
	  cursor: pointer;
	  background-color: #2196F3;
	  color: white;
	}

	.share-box button:hover {
	  background-color: #1976D2;
	}

/* Style général des sections sauf celle du bouton */
section:not(#tutorial-toggle-section) {
  max-width: 700px;
  margin: 2em auto;
  padding: 1em;
  line-height: 1.6;
}

/* SECTION : centrage du bouton dans la zone dédiée */
#tutorial-toggle-section {
  display: flex;
  justify-content: center;       /* Centre horizontalement */
  align-items: center;           /* Centre verticalement si nécessaire */
  margin: 2em auto;
  padding: 1em;
  width: 100%;
  max-width: 700px;              /* Comme les autres sections */
  box-sizing: border-box;
  text-align: center;            /* utile en fallback */
}

/* BOUTON : stylé et centré */
#show-tutorial-btn {
  display: inline-block;
  padding: 0.6em 1.2em;
  font-size: 1em;
  cursor: pointer;
  background-color: #2196F3;
  color: white;
  border: none;
  border-radius: 8px;
  box-shadow: 2px 2px 6px rgba(0,0,0,0.1);
  transition: background-color 0.3s ease, transform 0.2s ease;
}

#show-tutorial-btn:hover {
  background-color: #1976D2;
  transform: scale(1.05);
}

/* -- Cacher par défaut si nécessaire (à activer avec JS) -- */
/*
#show-tutorial-btn {
  display: none;
}
*/

/* RESPONSIVE DESIGN (facultatif mais recommandé) */
@media screen and (max-width: 480px) {
  #show-tutorial-btn {
    width: 90%;
    font-size: 1.1em;
  }
}