.reaction-product-tool {
    max-width: 850px;
    margin: 30px auto;
    padding: 28px;
    background: #ffffff;
    border: 1px solid #e2e2e2;
    border-radius: 12px;
    box-sizing: border-box;
}

.reaction-product-header {
    margin-bottom: 24px;
}

.reaction-product-header h2 {
    margin: 0 0 10px;
    font-size: 28px;
    line-height: 1.25;
}

.reaction-product-header p {
    margin: 0;
    font-size: 16px;
    line-height: 1.6;
}


/* Controls */

.reaction-product-controls {
    display: flex;
    justify-content: flex-end;
    margin-bottom: 20px;
}

.reaction-product-new-question,
.reaction-product-check-answer {
    padding: 10px 18px;
    border: 0;
    border-radius: 6px;
    cursor: pointer;
    font-size: 15px;
    font-weight: 600;
}

.reaction-product-new-question {
    background: #eeeeee;
    color: #222222;
}

.reaction-product-new-question:hover {
    background: #dddddd;
}

.reaction-product-check-answer {
    background: #222222;
    color: #ffffff;
}

.reaction-product-check-answer:hover {
    opacity: 0.88;
}

.reaction-product-check-answer:disabled {
    opacity: 0.5;
    cursor: default;
}


/* Question card */

.reaction-product-question {
    padding: 25px;
    border: 1px solid #dddddd;
    border-radius: 10px;
    background: #fafafa;
}

.reaction-product-question-number {
    margin-bottom: 22px;
    font-size: 14px;
    font-weight: 600;
    color: #666666;
}


/* Word equation */

.reaction-product-equation {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 12px;
    margin: 30px 0;
    font-size: 22px;
    font-weight: 600;
    line-height: 1.5;
    text-align: center;
}

.reaction-product-plus {
    font-weight: 400;
}

.reaction-product-arrow {
    padding: 0 8px;
    font-size: 28px;
    font-weight: 400;
}

.reaction-product-unknown {
    min-width: 45px;
    padding: 4px 12px;
    border-bottom: 2px solid #555555;
    text-align: center;
}


/* Conditions */

.reaction-product-conditions-wrapper {
    margin: 20px 0 28px;
    padding: 14px 16px;
    background: #ffffff;
    border-left: 4px solid #777777;
    line-height: 1.5;
}


/* Answer */

.reaction-product-answer-area {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 20px;
}

.reaction-product-answer-area label {
    font-weight: 600;
}

.reaction-product-answer {
    flex: 1;
    min-width: 220px;
    padding: 11px 12px;
    border: 1px solid #bbbbbb;
    border-radius: 6px;
    background: #ffffff;
    font-size: 16px;
    box-sizing: border-box;
}

.reaction-product-answer:focus {
    outline: 2px solid #999999;
    outline-offset: 1px;
}

.reaction-product-answer:disabled {
    background: #eeeeee;
}


/* Feedback */

.reaction-product-feedback {
    margin-top: 20px;
    padding: 0;
    line-height: 1.5;
}

.reaction-product-feedback-correct,
.reaction-product-feedback-incorrect,
.reaction-product-feedback-warning {
    padding: 14px 16px;
    border-radius: 6px;
}

.reaction-product-feedback-correct {
    background: #e8f5e9;
    border: 1px solid #a5d6a7;
}

.reaction-product-feedback-incorrect {
    background: #ffebee;
    border: 1px solid #ef9a9a;
}

.reaction-product-feedback-warning {
    background: #fff8e1;
    border: 1px solid #ffe082;
}


/* Explanation */

.reaction-product-explanation {
    margin-top: 12px;
    padding: 14px 16px;
    background: #ffffff;
    border: 1px solid #dddddd;
    border-radius: 6px;
    line-height: 1.6;
}


/* Mobile */

@media (max-width: 600px) {

    .reaction-product-tool {
        margin: 15px auto;
        padding: 18px;
    }

    .reaction-product-question {
        padding: 18px;
    }

    .reaction-product-equation {
        font-size: 18px;
        gap: 8px;
    }

    .reaction-product-arrow {
        font-size: 23px;
        padding: 0 3px;
    }

    .reaction-product-answer-area {
        display: block;
    }

    .reaction-product-answer-area label {
        display: block;
        margin-bottom: 8px;
    }

    .reaction-product-answer {
        width: 100%;
        margin-bottom: 12px;
    }

    .reaction-product-check-answer {
        width: 100%;
    }

    .reaction-product-controls {
        justify-content: stretch;
    }

    .reaction-product-new-question {
        width: 100%;
    }
}