.tool-section {
    padding: 2.5rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

label {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-secondary);
    margin-bottom: 0.6rem;
    font-weight: 600;
    display: block;
}

.category-selector-container {
    max-width: 400px;
    margin: 0 auto;
    width: 100%;
}

.select-wrapper {
    position: relative;
    width: 100%;
}

.select-wrapper::after {
    content: "▼";
    font-size: 0.8rem;
    color: var(--text-primary);
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    pointer-events: none;
}

.custom-select {
    width: 100%;
    padding: 1rem;
    padding-right: 2.5rem;
    border-radius: 12px;
    border: 1px solid var(--glass-border);
    background: var(--input-bg);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    appearance: none;
    -webkit-appearance: none;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.2);
}

.custom-select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(136, 189, 242, 0.2);
}

.custom-select option {
    background-color: var(--bg-slate);
    color: var(--text-primary);
}

.converter-layout {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    background: rgba(0, 0, 0, 0.03);
    padding: 2rem;
    border-radius: 20px;
    border: 1px solid rgba(0, 0, 0, 0.08);
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.2);
}

@media (max-width: 768px) {
    .converter-layout {
        flex-direction: column;
        gap: 2rem;
    }
}

.converter-box {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    width: 100%;
}

.unit-input {
    width: 100%;
    padding: 1rem;
    border-radius: 12px;
    border: 1px solid var(--glass-border);
    background: var(--input-bg);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1.5rem;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.2);
}

.unit-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(136, 189, 242, 0.2);
}

.unit-input::-webkit-outer-spin-button,
.unit-input::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
.unit-input[type="number"] {
    appearance: textfield;
    -moz-appearance: textfield;
}

.exchange-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--primary-transparent);
    color: var(--text-primary);
    flex-shrink: 0;
    margin-top: 1.5rem;
}

@media (max-width: 768px) {
    .exchange-icon {
        margin-top: 0;
        transform: rotate(90deg);
    }
}

.formula-display {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.95rem;
    padding: 1rem;
    background: rgba(136, 189, 242, 0.1);
    border-radius: 8px;
    border: 1px solid var(--glass-border);
}