.k24-calculator {
    margin: 24px 0;
    padding: 20px;
    border: 1px solid #ddd;
    border-radius: 8px;
    background: #fff;
}

.k24-calculator__title {
    margin: 0 0 18px;
    font-size: 1.25em;
}

.k24-calculator__form {
    display: grid;
    gap: 16px;
}

.k24-calculator__field label,
.k24-calculator__field legend {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
}

.k24-calculator__field fieldset {
    margin: 0;
    padding: 0;
    border: 0;
}

.k24-calculator__field input[type="text"],
.k24-calculator__field input[type="number"],
.k24-calculator__field select {
    box-sizing: border-box;
    width: 100%;
    min-height: 44px;
    padding: 9px 11px;
    border: 1px solid #bbb;
    border-radius: 5px;
    font: inherit;
    background: #fff;
}

.k24-calculator__input-wrap {
    display: flex;
    align-items: center;
    gap: 8px;
}

.k24-calculator__unit {
    flex: 0 0 auto;
    color: #555;
}

.k24-calculator__radios {
    display: flex;
    flex-wrap: wrap;
    gap: 10px 16px;
}

.k24-calculator__radios label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin: 0;
    font-weight: 400;
}

.k24-calculator__button {
    width: fit-content;
    min-height: 44px;
    padding: 10px 18px;
    border: 0;
    border-radius: 5px;
    cursor: pointer;
    font: inherit;
    font-weight: 700;
    color: #fff;
    background: #222;
}

.k24-calculator__button:hover,
.k24-calculator__button:focus-visible {
    background: #000;
}

.k24-calculator__message {
    color: #b32d2e;
}

.k24-calculator__message:empty {
    display: none;
}

.k24-calculator__result {
    padding: 14px 16px;
    border-radius: 6px;
    background: #f3f4f5;
}

.k24-calculator__result-label {
    display: block;
    margin-bottom: 3px;
    color: #555;
    font-size: .9em;
}

.k24-calculator__result-value {
    font-size: 1.35em;
}

@media (max-width: 480px) {
    .k24-calculator {
        padding: 16px;
    }

    .k24-calculator__input-wrap {
        align-items: stretch;
        flex-direction: column;
    }
}