html, body {
    height: 100%;
    margin: 0;
    padding: 0;
    font-family: Arial, sans-serif;
    color: #333;
    background: linear-gradient(135deg, #f5f0e6 0%, #e7ddca 10%, #dacdb2 20%, #cdbf9a 30%, #c1b383 40%, #b59b6d 50%, #aa8658 60%, #9f7243 70%, #955e2f 80%, #8a4a1c 90%, #0f172a 100% );
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-size: cover;
    padding: 20px;
    box-sizing: border-box;
}

h1 {
    text-align: center;
    margin-bottom: 20px;
}

/* Barra de progreso */

.progress-container {
    width: 80%;
    height: 20px;
    background-color: #ddd;
    border-radius: 10px;
    margin: 0 auto 30px auto;
    overflow: hidden;
}

#progressBar {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, #78C841, #B4E50D);
    border-radius: 10px 0 0 10px;
    transition: width 0.5s ease;
}

/* Grid centrado y responsive */

.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
    max-width: 1100px;
    margin: 0 auto;
    justify-content: center;
}

/* Cuadros de cursos */

.course-box {
    background: #fff;
    border-radius: 10px;
    padding: 15px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.15);
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    font-weight: bold;
    color: #000000;
}

    .course-box:hover {
        transform: translateY(-6px);
        box-shadow: 0 6px 12px rgba(0,0,0,0.2);
    }

    .course-box img {
        width: 100px;
        height: 100px;
        object-fit: cover;
        border-radius: 10px;
        margin-bottom: 12px;
    }

/* Modal curso */

.modal {
    display: none;
    position: fixed;
    z-index: 999;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.6);
    overflow-y: auto;
}

.modal-content {
    background: #fff;
    margin: 40px auto;
    padding: 25px 30px;
    border-radius: 12px;
    max-width: 700px;
    position: relative;
}

.close-btn {
    position: absolute;
    top: 15px;
    right: 20px;
    font-size: 25px;
    font-weight: bold;
    color: #555;
    cursor: pointer;
}

    .close-btn:hover {
        color: #000;
    }

.modal-content h2 {
    margin-top: 0;
    color: #000000;
}

.modal-content section {
    margin-bottom: 20px;
}

.examples img {
    max-width: 100%;
    border-radius: 8px;
    margin-top: 10px;
    box-shadow: 0 3px 7px rgba(0,0,0,0.1);
}

.exercises textarea {
    width: 100%;
    min-height: 80px;
    border-radius: 6px;
    border: 1px solid #ccc;
    padding: 8px;
    resize: vertical;
}

.quiz-question {
    margin-bottom: 15px;
}

    .quiz-question p {
        margin: 0 0 8px 0;
    }

    .quiz-question label {
        display: block;
        margin-bottom: 4px;
        cursor: pointer;
    }

.quiz-result {
    font-weight: bold;
    margin-top: 10px;
    color: green;
}

.btn-submit {
    background: #4b0082;
    color: rgb(255, 255, 255);
    padding: 8px 15px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
}

    .btn-submit:hover {
        background: #6a28cc;
    }

/* Modal felicitaciones */

#congratsModal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.7);
    overflow: hidden;
}

    #congratsModal .modal-content {
        max-width: 400px;
        margin: 20% auto;
        text-align: center;
        padding: 30px 20px;
    }

    #congratsModal button {
        margin-top: 20px;
        padding: 10px 20px;
        background: #4b0082;
        border: none;
        border-radius: 6px;
        color: rgb(255, 255, 255);
        cursor: pointer;
    }

        #congratsModal button:hover {
            background: #6a28cc;
        }
        .btn-drive {
  background-color: #3D74B6;
  color: white;
  border: none;
  padding: 12px 24px;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 600;
  font-size: 16px;
  transition: background-color 0.3s ease;
  margin-top: 10px;
}

.btn-drive:hover {
  background-color: #2b4f86;
}