:root {
    --primary: #3498db;
    --success: #028f0e;
    --warning: #e74c3c;
    --bg-main: #f4f6f7;
    --card-bg: #ffffff;
    --text-dark: #2c3e50;
    --border-color: #bdc3c7;
}

.exercise-container {
    background-color: var(--card-bg);
    border-radius: 12px;
    padding: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    max-width: 650px;
    width: 100%;
    text-align: center;
    border: 1px solid #e2e8f0;
}

p.subtitle {
    color: #7f8c8d;
    font-size: 1.1rem;
    margin: 0 0 20px 0;
}

/* --- Target Number Display --- */
.number-box {
    background-color: #e8f4f8;
    display: inline-block;
    padding: 8px;
    border-radius: 8px;
    border: 2px solid var(--primary);
    margin-bottom: 20px;
}

    .number-box span {
        font-size: 1rem;
        color: #566573;
        display: block;
        text-transform: uppercase;
        letter-spacing: 1px;
    }

    .number-box strong {
        font-size: 3rem;
        color: var(--text-dark);
        letter-spacing: 2px;
    }

/* --- Hint System --- */
.hints-container {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 20px;
}

.hint-btn {
    background-color: transparent;
    color: var(--primary);
    font-size: 0.95rem;
    padding: 8px 16px;
    border-radius: 4px;
    cursor: pointer;
    border: 1px solid var(--primary);
    transition: all 0.2s;
    font-weight: bold;
}

    .hint-btn:hover {
        background-color: var(--primary);
        color: white;
    }

.hint-text {
    display: none;
    background-color: #f8f9f9;
    color: #5d6d7e;
    padding: 15px;
    border-radius: 6px;
    font-size: 1rem;
    margin-bottom: 20px;
    border-left: 4px solid var(--primary);
    text-align: left;
    line-height: 1.5;
}



.input-group {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    background-color: #fdfefe;
    padding: 3px 10px 6px 10px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}
.action-btn {
    background-color: var(--primary);
    color: white;
    border: none;
    padding: 15px 40px;
    font-size: 1.2rem;
    border-radius: 6px;
    cursor: pointer;
    font-family: inherit;
    font-weight: bold;
    transition: background-color 0.2s;
}

    .action-btn:hover {
        background-color: #2980b9;
    }

#feedback {

    font-size: 1.2rem;
    font-weight: bold;
    min-height: 30px;

    border-radius: 4px;
}

.info {
    color: darkblue;
}

.correct {
    color: var(--success);

}

.wrong {
    color: var(--warning);
}