#scrollTopBtn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 999;
    background-color: #1E88E5;
    color: white;
    border: none;
    padding: 12px 16px;
    border-radius: 50%;
    font-size: 20px;
    cursor: pointer;
    display: none;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
    transition: background-color 0.3s, transform 0.3s;
}

#scrollTopBtn:hover {
    background-color: #00E676;
    transform: scale(1.1);
}

body {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    font-family: Arial, sans-serif;
    margin-top: 0px;
    margin-left: 250px;
    margin-right: 250px;
    padding: 0;
    background-color: #212121;
    color: #FAFAFA;
}

header {
    background-color: #1E88E5;
    color: #FAFAFA;
    padding: 15px;
    text-align: center;
    box-sizing: border-box;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    display: flex;
    max-width: calc(100% - 500px); /* largeur du body (250px à gauche + droite) */
    margin: 0 auto;
    border-radius: 0 0 12px 12px; /* joli arrondi en bas */
      /* 🎨 Style glassmorphism */
    background-color: rgba(30, 136, 229, 0.6); /* Bleu + transparence */
    backdrop-filter: blur(10px); /* Flou derrière */
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    color: #FAFAFA;

}



.header-logo {
    height: 60px;
    width: auto;
}
  
.header-title {
    font-size: 24px;
    font-weight: bold;
    flex: 1;
    text-align: center;
    margin: 0;
}

nav ul {
    display: flex;
    gap: 20px;
    list-style-type: none;
    margin: 0;
    padding: 0;
}

nav ul li {
    display: inline;
    margin: 0 15px;
}

nav ul li a {
    color: #FAFAFA;
    margin-left: 20px;
    text-decoration: none;
    font-weight: bold;
    transition: color 0.3s;
}
nav ul li a:hover {
    color: #00E676;
    text-decoration: underline;
}

header.scrolled {
    background-color: rgba(30, 136, 229, 0.85);
    padding: 8px 30px;
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.4);
    transition: all 0.3s ease;
}

header .header-title {
    transition: font-size 0.3s ease;
}
  
header.scrolled .header-title {
    font-size: 20px;
}

main {
    flex: 1; /* prend tout l’espace disponible */
    padding: 120px 20px 20px; /* Ajoute du padding en haut pour compenser le header fixe */
}

section {
    background-color: #1A1A1A;
    padding: 20px;
    border-radius: 12px;
    margin: 20px 0;
}

#methodes-resolution {
    background-color: #1e1e2f; /* fond doux */
    padding: 2rem;
    border-radius: 1rem;
    color: #f0f0f0;
    line-height: 1.6;
    font-size: 1.1rem;
}
  
#methodes-resolution h2 {
    color: #4fc3f7;
    font-size: 2rem;
    margin-bottom: 1.5rem;
    text-align: center;
}
  
#methodes-resolution article {
    background-color: #29293d;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border-radius: 1rem;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    transition: transform 0.2s;
}
  
#methodes-resolution article:hover {
    transform: scale(1.02);
}
  
#methodes-resolution h3 {
    color: #f48fb1;
    margin-bottom: 0.5rem;
    font-size: 1.5rem;
}
  
#methodes-resolution h4 {
    color: #ce93d8;
    margin-top: 1rem;
    font-size: 1.2rem;
}
  
#methodes-resolution a {
    color: #81d4fa;
    text-decoration: underline; 
}
  
#methodes-resolution a:hover {
    color: #ffffff;
    text-decoration: none;
}
  
#methodes-resolution ul {
    padding-left: 1.5rem;
    margin-top: 0.5rem;
    margin-bottom: 1rem;
}
  
 #methodes-resolution li {
    margin-bottom: 0.5rem;
}

.training-tools {
    margin-top: 40px;
    background-color: #1a1a1a;
    border-radius: 12px;
    padding: 20px;
}
  
.training-tools article {
    background-color: #2a2a2a;
    padding: 20px;
    margin: 20px 0;
    border-left: 6px solid #00E676;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 230, 118, 0.2);
}
  
.scramble-box, .timer-box {
    margin-top: 15px;
    padding: 15px;
    background-color: #212121;
    border-radius: 8px;
    text-align: center;
    color: #FAFAFA;
}
  
#scramble-text {
    font-size: 1.1rem;
    margin-bottom: 10px;
    color: #BBDEFB;
}
  
button {
    padding: 10px 20px;
    background-color: #1E88E5;
    color: #FAFAFA;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: bold;
}
  
button:hover {
    background-color: #1565C0;
}
  
.timer-box {
    cursor: pointer;
    user-select: none;
    font-size: 2rem;
    font-weight: bold;
    color: #00E676;
}

footer {
    background-color: #1A1A1A;
    color: #FAFAFA;
    text-align: center;
    padding: 20px 0;
    font-size: 0.9em;
    border-top: 1px solid #333;
    box-shadow: 0 -2px 6px rgba(0, 0, 0, 0.4);
}