.roas-calc-wrapper {
    max-width: 320px;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
}

.roas-calc-wrapper label {
    display: block;
    margin: 12px 0 4px;
    font-weight: 600;
}

.roas-input {
    width: 100%;
    padding: 8px;
    font-size: 15px;
    border: 1px solid #ccc;
    border-radius: 4px;
    box-sizing: border-box;
    transition: border-color .2s;
}

.roas-input.roas-error {
    border-color: #d63638;
    box-shadow: 0 0 0 1px #d63638;
}

.roas-btn {
    margin-top: 14px;
    padding: 8px 18px;
    font-size: 15px;
    cursor: pointer;
}

.roas-result {
    margin-top: 15px;
    font-weight: 700;
    font-size: 17px;
    color: #0066cc;
    min-height: 1.4em; /* prevent layout shift */
}

.roas-result.roas-error {
    color: #d63638;
}