.tool-label {
        display: block;
        font-size: 13px;
        font-weight: 600;
        color: var(--text-light);
        text-transform: uppercase;
        letter-spacing: 0.5px;
        margin-bottom: 8px;
    }
    .tool-input {
        padding: 12px 16px;
        border: 1px solid var(--border-light);
        border-radius: 8px;
        font-size: 14px;
        background: var(--bg-light);
        color: var(--text-dark);
        transition: border-color 0.2s;
    }
    .tool-input:focus {
        outline: none;
        border-color: var(--primary-light);
        box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
    }
    .tool-select {
        padding: 12px 16px;
        border: 1px solid var(--border-light);
        border-radius: 8px;
        font-size: 14px;
        background: var(--bg-white);
        color: var(--text-dark);
        cursor: pointer;
        width: 100%;
    }
    .tool-select:focus { outline: none; border-color: var(--primary-light); }
    .category-tabs {
        display: flex;
        gap: 8px;
        margin-bottom: 24px;
        flex-wrap: wrap;
    }
    .category-tab {
        padding: 10px 16px;
        border: 1px solid var(--border-light);
        background: var(--bg-white);
        border-radius: 8px;
        font-size: 13px;
        cursor: pointer;
        transition: all 0.2s;
        color: var(--text-medium);
        display: flex;
        align-items: center;
        gap: 6px;
    }
    .category-tab:hover { border-color: var(--primary-light); color: var(--primary); }
    .category-tab.active {
        background: var(--primary);
        color: white;
        border-color: var(--primary);
    }
    .category-tab i { font-size: 14px; }
    .swap-btn {
        width: 44px;
        height: 44px;
        border: 1px solid var(--border-light);
        background: var(--bg-white);
        border-radius: 50%;
        cursor: pointer;
        color: var(--primary);
        display: flex;
        align-items: center;
        justify-content: center;
        transition: all 0.2s;
        margin-bottom: 4px;
    }
    .swap-btn:hover { background: var(--primary); color: white; border-color: var(--primary); }
    .result-box {
        background: linear-gradient(135deg, #dbeafe, #ede9fe);
        border-radius: 12px;
        padding: 24px;
        text-align: center;
    }
    .result-amount {
        font-size: 32px;
        font-weight: 700;
        color: var(--primary);
        margin-bottom: 8px;
        word-break: break-all;
    }
    .result-text {
        font-size: 15px;
        color: var(--text-medium);
    }
    .formula-box {
        margin-top: 16px;
        padding: 12px 16px;
        background: var(--bg-light);
        border-radius: 8px;
        font-size: 13px;
        color: var(--text-medium);
        font-family: 'SF Mono', monospace;
        text-align: center;
    }
    .quick-ref {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
    }
    .quick-ref-item {
        padding: 10px 12px;
        background: var(--bg-light);
        border-radius: 6px;
        font-size: 13px;
        display: flex;
        justify-content: space-between;
    }
    .quick-ref-item span:first-child { color: var(--text-medium); }
    .quick-ref-item span:last-child { color: var(--primary); font-family: monospace; }
    @media (max-width: 768px) {
        .converter-grid { grid-template-columns: 1fr !important; }
        .swap-btn { margin: 8px auto; transform: rotate(90deg); }
        .result-amount { font-size: 24px; }
        .quick-ref { grid-template-columns: 1fr; }
        .category-tabs { justify-content: center; }
    }