* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Roboto, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #f4f4f4;
}

.calc-title {
    margin-bottom: 30px;
}

.calculator-container {
    position: relative;
}

.calculator {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    padding: 30px;
    width: 320px;
    text-align: center;
}

.form-group {
    margin-bottom: 15px;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

.number-input {
    width: 100%;
    padding: 10px;
    margin: 4px 0;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-sizing: border-box;
}

.number-input::placeholder {
    font-family: Roboto, sans-serif;
    font-size: 14px;
}

.btn {
    font-size: 14px;
    background-color: #3498db;
    color: white;
    padding: 12px 20px;
    margin-top: 10px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    width: 100%;
}

button:hover {
    background-color: #2980b9;
}

button:active {
    background-color: #2471a3;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
    transform: translateY(1px);
}

.results-container {
    position: absolute;
    margin-top: 20px;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    padding: 10px;
    max-width: 260px;
    width: 100%;
    text-align: center;
}

.results {
    font-weight: 400;
    padding: 10px 20px;
}

.results p:first-child {
    margin-bottom: 12px;
}

.hidden {
    display: none;
}

@media (max-width: 480px) {
    .calculator {
        width: 90%;
    }
}