* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
        }
        
        body {
            background: #f8fafc;
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 16px;
        }
        
        .converter-container {
            max-width: 600px;
            width: 100%;
            background: white;
            border-radius: 16px;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
            padding: 28px 24px;
        }
        
        h1 {
            font-size: 1.8rem;
            font-weight: 600;
            color: #111;
            margin-bottom: 8px;
            letter-spacing: -0.01em;
        }
        
        .subtitle {
            color: #5f5f5f;
            font-size: 0.95rem;
            margin-bottom: 28px;
            padding-bottom: 16px;
            border-bottom: 1px solid #eaeef2;
        }
        
        .tabs {
            display: flex;
            gap: 4px;
            background: #f1f5f9;
            padding: 4px;
            border-radius: 40px;
            margin-bottom: 28px;
        }
        
        .tab {
            flex: 1;
            text-align: center;
            padding: 10px 0;
            border-radius: 30px;
            background: transparent;
            border: none;
            font-size: 1rem;
            font-weight: 500;
            color: #4b5565;
            cursor: pointer;
            transition: 0.15s;
        }
        
        .tab.active {
            background: white;
            color: #111;
            box-shadow: 0 2px 8px rgba(0,0,0,0.04);
            font-weight: 500;
        }
        
        .converter-panel {
            display: none;
        }
        
        .converter-panel.active {
            display: block;
        }
        
        .input-block {
            margin-bottom: 16px;
        }
        
        .input-label {
            display: flex;
            justify-content: space-between;
            color: #3f3f3f;
            font-size: 0.9rem;
            margin-bottom: 6px;
        }
        
        .input-unit-group {
            display: flex;
            align-items: center;
            border: 1px solid #d0d9e2;
            border-radius: 12px;
            background: white;
            overflow: hidden;
        }
        
        .input-unit-group input {
            flex: 1;
            padding: 14px 16px;
            border: none;
            font-size: 1.1rem;
            outline: none;
            background: transparent;
        }
        
        .input-unit-group input[readonly] {
            background: #f8fafd;
            color: #1a1a1a;
        }
        
        .unit-select {
            padding: 0 14px;
            background: #f4f7fb;
            height: 100%;
            display: flex;
            align-items: center;
            border-left: 1px solid #d0d9e2;
            cursor: pointer;
        }
        
        .unit-select select {
            border: none;
            background: transparent;
            font-size: 1rem;
            font-weight: 500;
            color: #2d3b4f;
            outline: none;
            cursor: pointer;
            padding: 8px 0;
        }
        
        .swap-button {
            display: flex;
            justify-content: center;
            margin: 12px 0;
        }
        
        .swap-btn {
            width: 44px;
            height: 44px;
            border-radius: 40px;
            background: #f1f5f9;
            border: 1px solid #dde3ea;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.4rem;
            cursor: pointer;
            color: #3f4a5a;
            transition: 0.15s;
        }
        
        .swap-btn:hover {
            background: #e5eefc;
            border-color: #b0c0d0;
        }
        
        .result-panel {
            background: #f1f6fc;
            border-radius: 14px;
            padding: 20px;
            margin-top: 24px;
        }
        
        .result-main {
            display: flex;
            justify-content: space-between;
            align-items: baseline;
            margin-bottom: 12px;
        }
        
        .result-main .label {
            color: #475569;
        }
        
        .result-main .value {
            font-size: 2rem;
            font-weight: 600;
            color: #0a1e2f;
        }
        
        .result-main .unit {
            font-size: 1rem;
            color: #65758b;
            margin-left: 6px;
        }
        
        .result-additional {
            font-size: 0.95rem;
            color: #3b4f64;
            border-top: 1px dashed #b9ccdd;
            padding-top: 12px;
            display: flex;
            justify-content: space-between;
        }
        
        .reference-table {
            margin-top: 24px;
            background: #fbfdff;
            border-radius: 12px;
            padding: 16px;
            border: 1px solid #e5ebf2;
            font-size: 0.9rem;
        }
        
        .reference-table h3 {
            font-weight: 600;
            font-size: 0.95rem;
            margin-bottom: 12px;
            color: #1f2a3c;
        }
        
        .ref-grid {
            display: flex;
            flex-wrap: wrap;
            gap: 16px 28px;
            color: #3d506a;
        }
        
        .ref-item {
            display: flex;
            gap: 4px;
        }
        
        .ref-item span:first-child {
            font-weight: 500;
            color: #0a1a2c;
        }
        
        .footer-note {
            text-align: center;
            margin-top: 20px;
            color: #7e8b9c;
            font-size: 0.8rem;
            border-top: 1px solid #e2e8f0;
            padding-top: 18px;
        }
        
        @media (max-width: 450px) {
            .converter-container { padding: 20px; }
            .result-main .value { font-size: 1.6rem; }
            .unit-select select { font-size: 0.9rem; }
        }