* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
            background: #f4f8fe;
            color: #0b1f31;
            padding: 2rem 1rem;
            line-height: 1.5;
        }

        .container {
            max-width: 1280px;
            margin: 0 auto;
            background: #ffffff;
            border-radius: 40px;
            box-shadow: 0 30px 70px rgba(0, 20, 40, 0.06);
            padding: 2.5rem 2.5rem;
        }

        .page-header {
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 2rem;
            border-bottom: 2px solid #ebf2fa;
            padding-bottom: 1.2rem;
        }

        .page-header h1 {
            font-size: 2rem;
            font-weight: 700;
            color: #062031;
        }

        .page-header .sub {
            color: #3a5e7a;
            font-size: 0.95rem;
        }

        .badge-coupler {
            background: #e7effa;
            padding: 0.4rem 1.2rem;
            border-radius: 60px;
            font-weight: 600;
            font-size: 0.85rem;
            color: #124074;
            border: 1px solid #d3e0f0;
            display: inline-flex;
            align-items: center;
            gap: 8px;
        }

        .selection-area {
            display: grid;
            grid-template-columns: 1fr 380px;
            gap: 2rem;
            margin-top: 0.5rem;
        }

        @media (max-width: 820px) {
            .selection-area {
                grid-template-columns: 1fr;
                gap: 1.5rem;
            }
        }

        .module-panel h2 {
            font-size: 1.1rem;
            font-weight: 600;
            color: #062031;
            margin-bottom: 0.8rem;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .module-group {
            margin-bottom: 1.5rem;
        }

        .module-group .group-title {
            font-size: 0.8rem;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 0.4px;
            color: #4f7393;
            background: #f0f5fc;
            padding: 0.2rem 0.8rem;
            border-radius: 20px;
            display: inline-block;
            margin-bottom: 0.5rem;
        }

        .module-row {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
            padding: 0.45rem 0.7rem;
            border-radius: 12px;
            background: #f9fcff;
            border: 1px solid #eaf0f8;
            margin-bottom: 0.4rem;
            transition: 0.15s;
            gap: 0.3rem 0.6rem;
        }

        .module-row:hover {
            border-color: #b8cff0;
            background: #f4faff;
        }

        .module-row .info {
            display: flex;
            flex-wrap: wrap;
            align-items: baseline;
            gap: 0.3rem 0.8rem;
            flex: 1;
            min-width: 140px;
        }

        .module-row .model {
            font-weight: 700;
            font-size: 0.9rem;
            color: #062031;
            min-width: 60px;
        }

        .module-row .desc {
            font-size: 0.85rem;
            color: #2f5272;
        }

        .module-row .ch {
            font-size: 0.7rem;
            background: #e2ebf6;
            padding: 0.05rem 0.7rem;
            border-radius: 30px;
            color: #1a4a72;
            font-weight: 600;
        }

        .qty-control {
            display: inline-flex;
            align-items: center;
            gap: 0.2rem;
            background: #eef4fa;
            border-radius: 40px;
            padding: 0.05rem 0.3rem;
            border: 1px solid #dbe5f0;
        }

        .qty-control button {
            background: none;
            border: none;
            font-weight: 700;
            font-size: 0.9rem;
            cursor: pointer;
            color: #1f6bc0;
            padding: 0 0.3rem;
            line-height: 1.6;
            min-width: 20px;
            border-radius: 30px;
        }

        .qty-control button:hover {
            background: #d0def0;
        }

        .qty-control .qty-num {
            font-weight: 600;
            font-size: 0.85rem;
            min-width: 20px;
            text-align: center;
            color: #062031;
        }

        .btn-add-row {
            background: #1f6bc0;
            color: white;
            border: none;
            border-radius: 40px;
            padding: 0.15rem 1.2rem;
            font-weight: 600;
            font-size: 0.75rem;
            cursor: pointer;
            transition: 0.15s;
            line-height: 1.9;
            white-space: nowrap;
        }

        .btn-add-row:hover {
            background: #0f4f96;
            transform: scale(1.02);
        }

        .btn-add-row:active {
            transform: scale(0.96);
        }

        .module-row.added {
            background: #e1f0e8;
            border-color: #a3c9b5;
        }

        .cart-panel {
            background: #f8fcff;
            border-radius: 28px;
            border: 1px solid #e6eff9;
            padding: 1.5rem 1.5rem 1.2rem;
            position: sticky;
            top: 1rem;
            align-self: start;
        }

        .cart-panel h2 {
            font-size: 1.1rem;
            font-weight: 700;
            color: #062031;
            display: flex;
            align-items: center;
            justify-content: space-between;
            border-bottom: 1px solid #e3ecf6;
            padding-bottom: 0.6rem;
            margin-bottom: 0.8rem;
        }

        .cart-empty {
            color: #6f8ba8;
            font-size: 0.9rem;
            padding: 0.8rem 0;
            text-align: center;
        }

        .cart-item {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 0.4rem 0;
            border-bottom: 1px solid #edf3fa;
        }

        .cart-item .left {
            display: flex;
            align-items: center;
            gap: 0.6rem;
            flex-wrap: wrap;
        }

        .cart-item .left .model {
            font-weight: 600;
            font-size: 0.9rem;
        }

        .cart-item .left .qty {
            background: #e2ebf6;
            border-radius: 30px;
            padding: 0 0.3rem;
            font-size: 0.75rem;
            font-weight: 600;
            color: #1a4a72;
            display: inline-flex;
            align-items: center;
            gap: 2px;
        }

        .cart-item .left .qty button {
            background: none;
            border: none;
            font-weight: 700;
            font-size: 0.9rem;
            cursor: pointer;
            color: #1f6bc0;
            padding: 0 0.2rem;
            line-height: 1.4;
        }

        .cart-item .left .qty button:hover {
            color: #0f4f96;
        }

        .btn-remove {
            background: none;
            border: none;
            color: #a0b8cf;
            cursor: pointer;
            font-size: 0.8rem;
            padding: 0 0.2rem;
        }

        .btn-remove:hover {
            color: #c0392b;
        }

        .cart-summary {
            margin-top: 1rem;
            padding-top: 0.8rem;
            border-top: 2px solid #e3ecf6;
        }

        .cart-summary .stat {
            display: flex;
            justify-content: space-between;
            font-size: 0.9rem;
            padding: 0.15rem 0;
        }

        .cart-summary .stat .label {
            color: #3a5e7a;
        }

        .cart-summary .stat .value {
            font-weight: 600;
            color: #062031;
        }

        .power-status {
            margin-top: 0.6rem;
            padding: 0.5rem 0.8rem;
            border-radius: 16px;
            font-size: 0.85rem;
            font-weight: 500;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .power-status.ok {
            background: #ddf0e6;
            color: #0b583a;
        }

        .power-status.warn {
            background: #fef1e0;
            color: #8f5600;
        }

        .cart-actions {
            display: flex;
            flex-wrap: wrap;
            gap: 0.6rem;
            margin-top: 1rem;
        }

        .btn-primary {
            background: #1f6bc0;
            color: white;
            border: none;
            border-radius: 60px;
            padding: 0.5rem 1.6rem;
            font-weight: 600;
            font-size: 0.9rem;
            cursor: pointer;
            transition: 0.15s;
            flex: 1;
            min-width: 100px;
        }

        .btn-primary:hover {
            background: #0f4f96;
        }

        .btn-secondary {
            background: #e7effa;
            color: #124074;
            border: 1px solid #d3e0f0;
            border-radius: 60px;
            padding: 0.5rem 1.6rem;
            font-weight: 600;
            font-size: 0.9rem;
            cursor: pointer;
            transition: 0.15s;
            flex: 1;
            min-width: 100px;
        }

        .btn-secondary:hover {
            background: #d5e3f5;
        }

        .result-box {
            background: #f0f5fc;
            border-radius: 16px;
            padding: 0.8rem 1rem;
            margin-top: 0.8rem;
            font-size: 0.8rem;
            font-family: 'SF Mono', 'Consolas', monospace;
            white-space: pre-wrap;
            word-break: break-all;
            border: 1px dashed #b8cff0;
            display: none;
            max-height: 200px;
            overflow-y: auto;
        }

        .result-box.show {
            display: block;
        }

        .toast {
            position: fixed;
            bottom: 2rem;
            left: 50%;
            transform: translateX(-50%);
            background: #1f2e3f;
            color: white;
            padding: 0.6rem 1.8rem;
            border-radius: 60px;
            font-size: 0.9rem;
            box-shadow: 0 8px 30px rgba(0,0,0,0.15);
            opacity: 0;
            transition: opacity 0.25s;
            pointer-events: none;
            z-index: 999;
        }

        .toast.show {
            opacity: 1;
        }

        @media (max-width: 480px) {
            .container { padding: 1.5rem 1rem; }
            .module-row { flex-wrap: wrap; gap: 0.3rem; }
            .module-row .info { gap: 0.2rem 0.6rem; }
            .cart-panel { padding: 1rem; }
            .cart-actions { flex-direction: column; }
        }