.percentage-calculator {
    max-width: 800px;
    min-height: 300px;
    margin: 20px auto 40px;
    padding: 20px;
    background: white;
    border-radius: 16px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.percentage-calculator h2 {
    text-align: center;
    color: #1f2937;
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 26px;
}

.calculator-grid {
    display: grid;
    grid-template-columns: 2fr 3fr;
    gap: 30px;
}

.input-section,
.result-section {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.input-group label {
    font-weight: 500;
    color: #4b5563;
}

.percentage-calculator input[type="text"] {
    padding: 9px 12px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 15px;
    background-color: #ffffff;
    color: #1f2937;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.percentage-calculator input[type="text"]:hover,
.percentage-calculator input[type="text"]:active {
    border-color: #a9a9a9;
    background-color: #ffffff;
    border-radius: 8px;
}

.percentage-calculator input[type="text"]:focus {
    outline: none;
    border-color: #52b5e6;
    box-shadow: 0 0 0 1px rgba(0, 114, 170, 0.15);
    background-color: #ffffff;
    border-radius: 8px;
}

.result-card {
    border-radius: 12px;
    padding: 20px;
    border: 1px solid #ddd;
    height: 100%;
}

.result-card h3 {
    margin-top: 0;
    color: #1f2937;
    border-bottom: 1px solid #e5e7eb;
    padding-bottom: 10px;
    font-size: 20px;
}

.result-display {
    font-size: 18px;
    margin: 20px 0;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    text-align: left;
    color: #ac2020;
    gap: 8px;
}

.result-output {
    color: green;
    font-weight: 500;
}

.calculation-steps {
    background: #f0f4ff;
    padding: 12px 15px;
    border-radius: 8px;
    font-size: 14px;
    color: #374151;
    visibility: hidden;
}

.calculation-steps p {
    margin: 8px 0;
}

.result-buttons {
    display: flex;
    gap: 10px;
    margin-top: 20px;
    justify-content: center;
}

.calc-action-btn {
    padding: 8px 12px;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    font-size: 16px;
    transition: background-color 0.2s, transform 0.1s;
    background: #f3f4f6;
}

.calc-action-btn:active {
    transform: scale(0.98);
}

#copy-btn,
#reset-btn {
    background-color: #0072aa;
    color: white;
    border-color: #0072aa;
}

#copy-btn:hover,
#reset-btn:hover,
.calc-action-btn:focus {
    background-color: #0072aa;
    border-color: #0072aa;
    box-shadow: none;
    outline: none;
}

.select-group {
    display: block;
}

#calc-type-label {
    display: block;
    margin-bottom: 6px;
    color: #4b5563;
    font-weight: 500;
    font-size: 16px;
}

.percentage-calculator .select-group select {
    width: 100%;
    padding: 8px 12px;
    /* right padding for arrow space */
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 400;
    appearance: none;
    /* Hide native arrow */
    -webkit-appearance: none;
    -moz-appearance: none;
    background: #ffffff url("data:image/svg+xml,%3Csvg width='16' height='16' viewBox='0 0 20 20' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M6 8L10 12L14 8' stroke='%236B7280' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") no-repeat right 5px center;
    background-size: 24px 24px;
    cursor: pointer;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.percentage-calculator .select-group select:hover,
.percentage-calculator .select-group select:active {
    border-color: #a9a9a9;
    background-color: #ffffff;
    border-radius: 8px;
}

.percentage-calculator .select-group select:focus {
    outline: none;
    border-color: #52b5e6;
    box-shadow: 0 0 0 1px rgba(0, 114, 170, 0.15);
    background-color: #ffffff;
    border-radius: 8px;
}

.faq-list {
    margin-top: 1rem;
}

.faq-list dt {
    font-weight: 500;
    font-size: 1.1em;
}

.faq-list dd {
    margin-left: 0;
    margin-top: 0.5rem;
    margin-bottom: 1rem;
    padding-left: 1rem;
    padding-bottom: 10px;
    border-bottom: 1px dashed #ddd;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .percentage-calculator {
        box-shadow: none;
        border-radius: 0;
        border-top: 1px solid #e5e7eb;
        border-bottom: 1px solid #e5e7eb;
        margin: 0 auto 40px;
        padding: 20px 0;
    }

    .calculator-grid {
        grid-template-columns: 1fr;
        gap: 10px;
    }

    .select-group select {
        width: 100%;
        font-size: 16px;
    }

    .input-group input {
        padding: 12px;
        font-size: 16px;
    }

    .result-card {
        height: 100%;
        border: none;
        border-radius: 0;
        padding: 20px 0;
    }

    .result-section {
        min-width: 0;
    }

    .calculation-steps {
        overflow-x: auto;
        padding: 12px 15px;
        font-size: 15px;
    }

    .calculation-steps p {
        white-space: nowrap;
        margin: 8px 0;
    }
}