:root {
            --dji-green: #00A651;
            --dji-dark: #1a1a1a;
            --gray-light: #f5f5f5;
            --gray-border: #e0e0e0;
        }
        
        body {
            background-color: #ffffff;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            color: #333;
            line-height: 1.6;
        }
        
        .header {
            background-color: #fff;
            border-bottom: 3px solid var(--dji-green);
            padding: 2rem 0;
            margin-bottom: 2rem;
        }
        
        .logo {
            font-size: 2.5rem;
            font-weight: bold;
            color: var(--dji-green);
        }
        
        .tagline {
            color: #666;
            font-size: 1.1rem;
            margin-top: 0.5rem;
        }
        
        .nav-tabs {
            border-bottom: 2px solid var(--gray-border);
            margin-bottom: 2rem;
        }
        
        .nav-tabs .nav-link {
            color: #666;
            border: none;
            padding: 1rem 2rem;
            font-weight: 600;
            font-size: 1.1rem;
            background: transparent;
        }
        
        .nav-tabs .nav-link.active {
            color: var(--dji-green);
            border-bottom: 3px solid var(--dji-green);
            background: transparent;
        }
        
        .card {
            border: 1px solid var(--gray-border);
            border-radius: 8px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.08);
            margin-bottom: 2rem;
            background: #fff;
        }
        
        .card-header {
            background-color: #fff;
            border-bottom: 2px solid var(--dji-green);
            padding: 1.5rem;
            font-weight: bold;
            font-size: 1.3rem;
            color: var(--dji-green);
            border-radius: 8px 8px 0 0 !important;
        }
        
        .card-body {
            padding: 2rem;
        }
        
        .drone-image-container {
            text-align: center;
            padding: 1rem;
            background: var(--gray-light);
            border-radius: 8px;
            margin-bottom: 1rem;
        }
        
        .drone-image {
            max-width: 100%;
            height: 180px;
            object-fit: contain;
        }
        
        .drone-placeholder {
            width: 100%;
            height: 180px;
            background: linear-gradient(135deg, #e8f5e9 0%, #c8e6c9 100%);
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 4rem;
            color: var(--dji-green);
        }
        
        .comparison-table {
            width: 100%;
            border-collapse: separate;
            border-spacing: 0;
            margin: 1rem 0;
        }
        
        .comparison-table thead {
            background-color: var(--dji-green);
            color: white;
        }
        
        .comparison-table th {
            padding: 1rem;
            font-weight: bold;
            text-align: left;
        }
        
        .comparison-table td {
            padding: 1rem;
            border-bottom: 1px solid var(--gray-border);
            vertical-align: middle;
        }
        
        .comparison-table tbody tr:hover {
            background-color: var(--gray-light);
        }
        
        .comparison-table tbody tr:nth-child(even) {
            background-color: #fafafa;
        }
        
        .badge-pro {
            background-color: #e8f5e9;
            color: var(--dji-green);
            padding: 0.4rem 0.8rem;
            border-radius: 20px;
            font-size: 0.85rem;
            margin: 0.2rem;
            display: inline-block;
            font-weight: 600;
        }
        
        .badge-contra {
            background-color: #ffebee;
            color: #c62828;
            padding: 0.4rem 0.8rem;
            border-radius: 20px;
            font-size: 0.85rem;
            margin: 0.2rem;
            display: inline-block;
            font-weight: 600;
        }
        
        .roi-card {
            background-color: var(--gray-light);
            border-left: 4px solid var(--dji-green);
            padding: 1.5rem;
            text-align: center;
            margin-bottom: 1rem;
            border-radius: 6px;
            min-height: 140px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
        }
        
        .roi-value-main {
            font-size: clamp(1.3rem, 4vw, 1.8rem);
            font-weight: bold;
            color: var(--dji-green);
            line-height: 1.2;
            word-break: break-word;
            max-width: 100%;
        }
        
        .roi-value-sub {
            font-size: clamp(1.1rem, 3.5vw, 1.5rem);
            font-weight: bold;
            color: #f57c00;
            line-height: 1.2;
            margin-top: 0.25rem;
        }
        
        .roi-label {
            color: #666;
            text-transform: uppercase;
            letter-spacing: 1px;
            font-size: clamp(0.65rem, 2vw, 0.75rem);
            margin-top: auto;
            padding-top: 0.5rem;
            text-align: center;
        }
        
        .spec-item {
            text-align: center;
            padding: 1rem;
        }
        
        .spec-icon {
            font-size: 2rem;
            color: var(--dji-green);
            margin-bottom: 0.5rem;
        }
        
        .spec-value {
            font-size: 1.3rem;
            font-weight: bold;
            color: #333;
            margin-bottom: 0.25rem;
        }
        
        .spec-label {
            color: #666;
            font-size: 0.85rem;
        }
        
        .case-card {
            border: 1px solid var(--gray-border);
            border-radius: 8px;
            padding: 1.5rem;
            margin-bottom: 1.5rem;
            background: #fff;
        }
        
        .case-header {
            color: var(--dji-green);
            font-weight: bold;
            font-size: 1.2rem;
            margin-bottom: 1rem;
        }
        
        .case-location {
            color: #666;
            font-size: 0.9rem;
            margin-bottom: 1rem;
        }
        
        .case-result {
            background: var(--gray-light);
            padding: 1rem;
            border-radius: 6px;
            margin-top: 1rem;
        }
        
        .form-label {
            color: #333;
            font-weight: 600;
            margin-bottom: 0.5rem;
        }
        
        .form-control, .form-select {
            border: 1px solid var(--gray-border);
            border-radius: 6px;
            padding: 0.75rem;
            font-size: 1rem;
        }
        
        .form-control:focus, .form-select:focus {
            border-color: var(--dji-green);
            box-shadow: 0 0 0 0.2rem rgba(0, 166, 81, 0.15);
        }
        
        .btn-calculate {
            background-color: var(--dji-green);
            color: white;
            border: none;
            padding: 1rem;
            font-size: 1.1rem;
            font-weight: bold;
            border-radius: 6px;
            width: 100%;
            margin-top: 1rem;
            transition: all 0.3s ease;
        }
        
        .btn-calculate:hover {
            background-color: #008f45;
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(0, 166, 81, 0.3);
        }
        
        .chart-container {
            position: relative;
            height: 300px;
            margin: 1rem 0;
        }
        
        .highlight-box {
            background-color: var(--gray-light);
            border-left: 4px solid var(--dji-green);
            padding: 1.5rem;
            border-radius: 6px;
            margin: 1.5rem 0;
        }
        
        .highlight-box h5 {
            color: var(--dji-green);
            margin-bottom: 1rem;
        }
        
        .advantage-card {
            background: var(--gray-light);
            padding: 1.5rem;
            border-radius: 8px;
            margin-bottom: 1rem;
            border-left: 4px solid var(--dji-green);
        }
        
        @media (max-width: 768px) {
            .logo { font-size: 1.8rem; }
            .nav-tabs .nav-link { padding: 0.75rem 1rem; font-size: 0.95rem; }
            .card-body { padding: 1.25rem; }
            .roi-card { min-height: 120px; padding: 1rem; }
        }
        
        @media print {
            .no-print { display: none !important; }
            body { background: white; }
            .card { box-shadow: none; border: 1px solid #ddd; }
        }