* { margin: 0; padding: 0; box-sizing: border-box; }
        body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; background: linear-gradient(135deg, #f5f7fa 0%, #e4e8ec 100%); min-height: 100vh; color: #2d3748; }
        .container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
        header { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: white; padding: 20px 0; box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1); position: sticky; top: 0; z-index: 100; }
        .header-content { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 15px; }
        .logo { font-size: 24px; font-weight: 700; text-decoration: none; color: white; display: flex; align-items: center; gap: 10px; }
        nav ul { display: flex; list-style: none; gap: 25px; }
        nav a { color: white; text-decoration: none; font-weight: 600; display: flex; align-items: center; gap: 5px; }
        .breadcrumb { background: white; padding: 15px 0; border-bottom: 1px solid #e2e8f0; }
        .breadcrumb-list { display: flex; align-items: center; gap: 10px; list-style: none; margin: 0; padding: 0; font-size: 14px; color: #718096; }
        .breadcrumb-list li { display: flex; align-items: center; }
        .breadcrumb-list a { color: #667eea; text-decoration: none; }
        .breadcrumb-list li::after { content: '/'; margin-left: 10px; color: #cbd5e0; }
        .breadcrumb-list li:last-child::after { display: none; }
        .main-content { padding: 40px 0; }
        .tool-section { background: white; border-radius: 20px; padding: 40px; box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08); margin-bottom: 40px; }
        .tool-header { text-align: center; margin-bottom: 40px; }
        .tool-header h1 { font-size: 32px; color: #2d3748; margin-bottom: 10px; }
        .tool-header h1 i { color: #667eea; margin-right: 10px; }
        .tool-header p { color: #718096; font-size: 16px; }
        .bmi-form { max-width: 500px; margin: 0 auto; }
        .form-group { margin-bottom: 20px; }
        .form-group label { display: block; margin-bottom: 8px; font-weight: 600; color: #2d3748; }
        .form-group input, .form-group select { width: 100%; padding: 14px 18px; font-size: 16px; border: 2px solid #e2e8f0; border-radius: 12px; transition: all 0.3s; }
        .form-group input:focus, .form-group select:focus { outline: none; border-color: #667eea; box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1); }
        .form-row { display: flex; gap: 15px; }
        .form-row .form-group { flex: 1; }
        .calc-btn { width: 100%; padding: 16px; background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: white; border: none; border-radius: 12px; font-size: 16px; font-weight: 600; cursor: pointer; transition: all 0.3s; }
        .calc-btn:hover { transform: translateY(-2px); box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4); }
        .result-box { margin-top: 30px; padding: 30px; border-radius: 15px; text-align: center; display: none; }
        .result-box.underweight { background: linear-gradient(135deg, #ebf8ff 0%, #bee3f8 100%); }
        .result-box.normal { background: linear-gradient(135deg, #f0fff4 0%, #c6f6d5 100%); }
        .result-box.overweight { background: linear-gradient(135deg, #fffaf0 0%, #feebc8 100%); }
        .result-box.obese { background: linear-gradient(135deg, #fff5f5 0%, #fed7d7 100%); }
        .bmi-value { font-size: 48px; font-weight: 700; margin-bottom: 10px; }
        .result-box.underweight .bmi-value { color: #2b6cb0; }
        .result-box.normal .bmi-value { color: #276749; }
        .result-box.overweight .bmi-value { color: #c05621; }
        .result-box.obese .bmi-value { color: #c53030; }
        .bmi-status { font-size: 20px; font-weight: 600; margin-bottom: 15px; }
        .bmi-range { font-size: 14px; color: #4a5568; }
        .bmi-scale { margin-top: 30px; padding: 20px; background: #f7fafc; border-radius: 10px; }
        .scale-bar { height: 20px; border-radius: 10px; background: linear-gradient(to right, #3182ce 0%, #3182ce 18.5%, #38a169 18.5%, #38a169 25%, #dd6b20 25%, #dd6b20 30%, #e53e3e 30%, #e53e3e 100%); position: relative; }
        .scale-labels { display: flex; justify-content: space-between; margin-top: 10px; font-size: 12px; color: #718096; }
        .scale-pointer { position: absolute; top: -8px; width: 4px; height: 36px; background: #2d3748; border-radius: 2px; display: none; }
        .info-section { background: white; border-radius: 15px; padding: 30px; box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05); }
        .info-section h2 { font-size: 20px; color: #2d3748; margin-bottom: 20px; display: flex; align-items: center; gap: 10px; }
        .info-section h2 i { color: #667eea; }
        .info-section p { color: #4a5568; margin-bottom: 15px; line-height: 1.8; }
        .bmi-table { width: 100%; border-collapse: collapse; margin-top: 20px; }
        .bmi-table th, .bmi-table td { padding: 12px 15px; text-align: left; border-bottom: 1px solid #e2e8f0; }
        .bmi-table th { background: #f7fafc; font-weight: 600; color: #2d3748; }
        .bmi-table td { color: #4a5568; }
        footer { background: #2d3748; color: #a0aec0; padding: 40px 0 20px; margin-top: 60px; }
        .footer-content { text-align: center; }
        .footer-links { display: flex; justify-content: center; gap: 20px; margin-bottom: 20px; flex-wrap: wrap; }
        .footer-links a { color: #a0aec0; text-decoration: none; }
        .copyright { font-size: 14px; color: #718096; }
        @media (max-width: 768px) {
            .header-content { flex-direction: column; text-align: center; }
            nav ul { flex-wrap: wrap; justify-content: center; }
            .tool-section { padding: 25px 15px; }
            .tool-header h1 { font-size: 24px; }
            .form-row { flex-direction: column; }
            .bmi-value { font-size: 36px; }
        }