.calculator-box {
    background: white;
    box-shadow: 0px 0px 15px rgba(0, 0, 0, 0.2);
    max-width: 700px;
    margin: 70px auto;
    padding: 30px;
    border-radius: 10px;
    width: 100%;
}

    .calculator-box h2 {
        text-align: center;
        margin-bottom: 20px;
        color: #2a5c91;
        font-family: 'Segoe UI', sans-serif;
    }

label {
    display: block;
    margin-top: 15px;
    font-weight: bold;
    color: #2a5c91;
}

input, select {
    width: 100%;
    padding: 10px;
    border-radius: 6px;
    border: 1px solid #ccc;
    font-size: 16px;
    margin-top: 5px;
    transition: border 0.3s;
    background: #f8faff;
}

    input.invalid, select.invalid {
        border: 2px solid #ff8800;
    }
.error-text {
    color: #ff8800;
    font-size: 13px;
    height: 16px;
    display: block;
}

::selection {
    background: #007BFF; /* Selection background */
    color: white; /* Selection text color */
}

.calculate-btn {
    background: #2a5c91;
    color: white;
    border: none;
    padding: 14px;
    border-radius: 8px;
    cursor: pointer;
    width: 100%;
    margin-bottom: 25px;
    margin-top: 34px;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s;
    box-shadow: 0 2px 8px rgba(0, 82, 204, 0.2);
}

    .calculate-btn:hover {
        opacity: 0.9;
    }

.result-box {
    margin-top: 25px;
    padding: 20px;
    border-radius: 10px;
    font-size: 18px;
    font-weight: bold;
    text-align: center;
}

.low {
    background: #d4edda;
    color: #155724;
}

.moderate {
    background: #fff3cd;
    color: #856404;
}

.high {
    background: #f8d7da;
    color: #721c24;
}

@media (max-width: 600px) {
    .calculator-box {
        padding: 20px;
        width: 90%;
        margin-top: 100px;
    }

    .calculate-btn {
        font-size: 15px;
        padding: 10px;
    }

    input, select {
        font-size: 15px;
    }
}