/*
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final author start
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Final Author @ Mohammad Aminul Islam
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final author end
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*/


/* calculator main body styling */
.calculator-main-bg {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 10px;
    margin-bottom: 10px;
    background-color: #eefafb;
}

/* calculator main styling */
.calculator-main {
    background-color: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    max-width: 400px;
    width: 100%;
}

/* heading styling */
h1 {
    text-align: center;
    font-size: 1.5em;
}

/* calculator grid styling */
.calculator {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
}

/* input and button styling */
.calculator input, .calculator button {
    padding: 15px;
    font-size: 1em;
    border: 1px solid #ddd;
    border-radius: 4px;
    text-align: center;
}

/* button specific styling */
.calculator button {
    background-color: #f0f0f0;
    cursor: pointer;
}

.calculator button:active {
    background-color: #ddd;
}

.calculator button:focus {
    outline: none;
}

/* output display styling */
.output {
    grid-column: span 4;
    background-color: #e9e9e9;
    text-align: right;
}

/* media queries for responsiveness */
@media (max-width: 600px) {
    .calculator-main {
        padding: 15px;
        max-width: 300px;
    }

    .calculator input, .calculator button {
        padding: 10px;
        font-size: 0.9em;
    }
}

@media (max-width: 400px) {
    .calculator {
        grid-template-columns: repeat(2, 1fr);
    }

    .calculator button, .calculator input {
        padding: 10px;
        font-size: 0.8em;
    }

    .output {
        grid-column: span 2;
    }

    .calculator button[style*="grid-column: span 4"] {
        grid-column: span 2;
    }
}