body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: #f9f9f9;
    color: #333;
    background-image: linear-gradient(
        rgba(0, 0, 0, 0.3),
        rgba(0, 0, 0, 0.3)
    ), url('./images/bg3.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    position: relative;
}

.container {
    display: flex;
    flex-wrap: wrap;
    max-width: 1200px;
    margin: 1cm 3cm 1cm 3cm;
    background: #fff;
    box-shadow: 0 0 50px rgba(0,0,0,0.1);
    opacity: 0.9;
    line-height: 0.7cm;
}

.left, .right {
    padding: 40px;
}

.left {
    flex: 1;
    min-width: 300px;
    background: #fff;
}

.left h1 {
    color: #003366;
    margin-bottom: 10px;
}

.left ul {
    list-style: none;
    padding: 0;
}

.left ul li {
    margin-bottom: 10px;
    position: relative;
    padding-left: 20px;
}

.left ul li::before {
    content: "+";
    position: absolute;
    left: 0;
    color: #cc0000;
    font-weight: bold;
}

.right {
    flex: 1;
    min-width: 300px;
    background: #fefefe;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.right img {
    max-width: 100%;
    height: auto;
    margin-bottom: 20px;
    box-shadow: 0px 0px 10px grey;
}

.form-box {
    background: #fff;
    padding: 20px;
    border: 1px solid #ddd;
    box-shadow: 0px 0px 8px grey;
}

.form-box h3 {
    color: #cc0000;
    margin-bottom: 15px;
}

.form-box input[type="text"],
.form-box input[type="email"],
.form-box input[type="tel"] {
    width: 94%;
    padding: 10px;
    margin-bottom: 10px;
    border: 1px solid #ccc;
    border-radius: 4px;
}

.form-box .gender {
    display: flex;
    margin-bottom: 10px;
}

.form-box .gender label {
    margin-right: 20px;
    font-size: 14px;
}

.form-box button {
    background-color: #cc0000;
    color: white;
    padding: 12px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    width: 100%;
    font-size: 16px;
    transition: background-color 0.3s;
}

.form-box button:hover {
    background-color: #990000;
}

.note {
    font-size: 12px;
    color: #666;
    margin-top: 10px;
}

strong{
    color: #003366;
    transition: color 0.3s ease-in-out;
}

strong:hover{
    color: red;
}

@media (max-width: 768px) {
    .container {
        flex-direction: column;
        margin: 0.3cm;
    }

    .left, .right {
        padding: 20px;
    }

    .form-box button {
        font-size: 14px;
    }

    footer {
        flex-direction: column;
        align-items: center;
        text-align: center;
        background-color: rgb(0, 0, 76);
        color: white;
        height: auto;
        width: 100vw;
        display: flex;
        justify-content: center;
        align-items: center;
        font-size: 0.45cm;
    }

    footer b {
        margin-top: 10px;
    }

    .left {
        order: 2; /* Xuống sau */
    }

    .right {
        order: 1; /* Lên trước */
    }
}

@media (min-width: 768px) {
    footer{
        background-color: rgb(0, 0, 76);
        color: white;
        height: auto;
        width: 100vw;
        display: flex;
        justify-content: center;
        align-items: center;
        font-size: 0.45cm;
    }

    footer p{
        margin-right: 3cm;
        margin-left: 0.5cm;
    }
}

#result {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: rgba(0, 128, 0, 0.9);
    color: white;
    padding: 15px 20px;
    font-size: 18px;
    font-weight: bold;
    text-align: center;
    display: none;
    z-index: 999;
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
  }