body {
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(to right, #1a1a1a, #333);
    color: white;
    margin: 0;
    padding: 0;
    text-align: center;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

h1 {
    margin-top: 100px;
    font-size: 2.8em;
    font-weight: bold;
    color: #ffffff;
}

#start-container {
    margin-top: 80px;
}

#start-btn {
    background: linear-gradient(45deg, #007bff, #0056b3);
    color: white;
    border: none;
    padding: 15px 40px;
    font-size: 1.4em;
    cursor: pointer;
    border-radius: 30px;
    transition: 0.3s ease-in-out;
    box-shadow: 0 4px 10px rgba(0, 123, 255, 0.3);
    font-weight: bold;
}

.about-slider {
    max-width: 700px;
    margin: 50px auto;
    padding: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.2);
    flex-grow: 1;
    overflow: hidden;
    transition: height 0.5s ease-in-out;
}

.slide {
    display: none;
    opacity: 0;
    animation: fadeInUp 1s forwards ease-in-out;
    padding: 20px;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

#final-buttons {
    display: none;
    margin-top: 50px;
    text-align: center;
}

.final-btn {
    background: linear-gradient(45deg, #ff7e5f, #ff3d00);
    color: white;
    border: none;
    padding: 12px 30px;
    font-size: 1.2em;
    cursor: pointer;
    border-radius: 25px;
    transition: 0.3s ease-in-out;
    box-shadow: 0 4px 10px rgba(255, 126, 95, 0.3);
    font-weight: bold;
    margin: 10px;
}

/* ✅ Correction du footer pour qu'il descende bien */
footer {
    width: 100%;
    background: black;
    color: white;
    text-align: center;
    position: relative;
    padding: 20px 0;
    margin-top: 50px;
    transition: margin-top 0.5s ease-in-out;
}