body {
    background: linear-gradient(135deg, #0056b3 0%, #002b5b 100%);
    overflow-y: auto;
    min-height: 100vh;
    color: #fff;
}

/* ส่วนที่ทำให้เรียง 3 ในจอคอม */
.es_col1 { 
    max-width: 33.333333%; 
    flex: 0 0 33.333333%; 
    padding: 10px; 
}

/* --- จุดที่เพิ่ม: ถ้าหน้าจอเล็กกว่า 992px (Tablet/Mobile) ให้เรียง 1 --- */
@media (max-width: 991px) {
    .es_col1 {
        max-width: 100%;
        flex: 0 0 100%;
    }
}

.es_frame1 { 
    width: 100%; height: 240px; position: relative; overflow: hidden; 
    border-radius: 15px; box-shadow: 0 8px 20px rgba(0,0,0,0.3);
    transition: transform 0.3s ease;
}
.es_frame1:hover { transform: translateY(-10px); }
.es_frame1 img { width: 100%; height: 100%; object-fit: cover; }
.es_label1 {
    position: absolute; bottom: 0; left: 0; right: 0;
    background: rgba(0, 0, 0, 0.7); color: #fff;
    padding: 15px; text-align: center; font-weight: bold;
}
.btn_search { background-color: #333; color: #fff; border: none; }
.btn_search:hover { background-color: #555; color: #fff; }
.manual-section {
    background-color: rgba(255, 255, 255, 0.95); border-radius: 20px;
    padding: 30px; margin-top: 40px; color: #333;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}
.manual-link {
    display: flex; align-items: center; padding: 12px 15px; margin-bottom: 10px;
    color: #333; text-decoration: none; border-radius: 12px;
    background: #f8f9fa; transition: all 0.2s;
}
.manual-link:hover { background-color: #e9ecef; transform: translateX(5px); }
.manual-link i { margin-right: 15px; color: #d9534f; font-size: 1.4rem; }