/*  LAYOUT CHÍNH  */
.page-wrapper {
    display: flex;
    justify-content: flex-start;
    align-items: flex-start;
    max-width: 1130px;
    margin: 20px 0 20px 10px;
    padding-left: 10px;
    padding-right: 20px;
    gap: 30px;
}

/*  QUẢNG CÁO BÊN TRÁI  */
.left-ads {
    width: 200px;
    flex-shrink: 0;
    background: white;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.1);
    height: fit-content;
    position: sticky;
    top: 20px;
}

.left-ads h3 {
    color: #1e88e5;
    margin-bottom: 10px;
}

.left-ads img {
    width: 100%;
    border-radius: 10px;
    margin: 15px 0;
}

.ads-btn {
    display: block;
    text-align: center;
    background: #1e88e5;
    color: white;
    padding: 10px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: bold;
    transition: 0.3s;
}

.ads-btn:hover {
    background: #1565c0;
}

/*  NỘI DUNG CHÍNH */
.introduce {
    flex: 1;
    background-color: #f9f9f9;
    padding: 25px;
    font-family: Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* Tiêu đề */
.introduce h2 {
    color: #2a7ae2;
    margin-top: 20px;
}

/* Khoảng cách nội dung */
.introduce p,
.introduce ul {
    margin-bottom: 15px;
}

.introduce ul {
    padding-left: 20px;
}

.introduce li {
    margin-bottom: 8px;
}

/*  HÌNH CHỨNG NHẬN  */
.certificate-image {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    margin: 20px 0;
}

.certificate-image img {
    width: 100%;
    max-width: 400px;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

/* RESPONSIVE MOBILE  */
@media (max-width: 992px) {
    .page-wrapper {
        flex-direction: column;
    }

    .left-ads {
        width: 100%;
        position: relative;
    }
}