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(max-width:768px){.calculators-hero{padding:3rem 0}.calculators-title{font-size:2.5rem}.calculators-subtitle{font-size:1.125rem}.calculators-stats{flex-direction:column;gap:1.5rem}.category-header{flex-direction:column;text-align:center}.popular-grid,.steps-grid,.tools-grid-modern{grid-template-columns:1fr}.help-actions{flex-direction:column;align-items:center}.help-actions .btn{width:100%;max-width:300px}.guides-grid{grid-template-columns:1fr;gap:1.5rem}.guide-card{padding:1.5rem}.faq-question{padding:1rem;font-size:1rem}.faq-answer.open{padding:1rem}.page-header h1{font-size:2rem}.page-description{font-size:1rem}.site-main{padding:0}.lang-menu{right:-1rem;left:auto}}.section-cta{margin-top:2rem;text-align:center}:root{--concrete-gray-25:#fafbfc;--concrete-gray-50:#f5f6f7;--concrete-gray-100:#e8eaed;--concrete-gray-200:#d1d5db;--concrete-gray-300:#b4bac4;--concrete-gray-400:#8a939f;--concrete-gray-500:#6b7280;--concrete-gray-600:#4b5563;--concrete-gray-700:#374151;--concrete-gray-800:#1f2937;--concrete-gray-900:#111827;--concrete-industrial-50:#f8fafc;--concrete-industrial-100:#f1f5f9;--concrete-industrial-200:#e2e8f0;--concrete-industrial-300:#cbd5e1;--concrete-industrial-400:#94a3b8;--concrete-industrial-500:#64748b;--concrete-industrial-600:#475569;--concrete-industrial-700:#334155;--concrete-industrial-800:#1e293b;--concrete-industrial-900:#0f172a;--construction-blue-50:#eff6ff;--construction-blue-100:#dbeafe;--construction-blue-200:#bfdbfe;--construction-blue-300:#93c5fd;--construction-blue-400:#60a5fa;--construction-blue-500:#3b82f6;--construction-blue-600:#2563eb;--construction-blue-700:#1d4ed8;--construction-blue-800:#1e40af;--construction-blue-900:#1e3a8a;--steel-blue-50:#f0f9ff;--steel-blue-100:#e0f2fe;--steel-blue-200:#bae6fd;--steel-blue-300:#7dd3fc;--steel-blue-400:#38bdf8;--steel-blue-500:#0ea5e9;--steel-blue-600:#0284c7;--steel-blue-700:#0369a1;--steel-blue-800:#075985;--steel-blue-900:#0c4a6e;--safety-orange-50:#fff7ed;--safety-orange-100:#ffedd5;--safety-orange-200:#fed7aa;--safety-orange-300:#fdba74;--safety-orange-400:#fb923c;--safety-orange-500:#f97316;--safety-orange-600:#ea580c;--safety-orange-700:#c2410c;--safety-orange-800:#9a3412;--safety-orange-900:#7c2d12;--construction-green-50:#f0fdf4;--construction-green-100:#dcfce7;--construction-green-200:#bbf7d0;--construction-green-300:#86efac;--construction-green-400:#4ade80;--construction-green-500:#22c55e;--construction-green-600:#16a34a;--construction-green-700:#15803d;--construction-green-800:#166534;--construction-green-900:#14532d;--warm-neutral-50:#fefefe;--warm-neutral-100:#f8f8f8;--warm-neutral-200:#f0f0f0;--warm-neutral-300:#e0e0e0;--warm-neutral-400:silver;--warm-neutral-500:#a0a0a0;--warm-neutral-600:grey;--warm-neutral-700:#606060;--warm-neutral-800:#404040;--warm-neutral-900:#202020;--brand:var(--steel-blue-600);--brand-light:var(--steel-blue-500);--brand-soft:var(--steel-blue-400);--brand-lighter:var(--steel-blue-100);--brand-dark:var(--steel-blue-700);--brand-gradient:var(--steel-blue-600);--brand-gradient-hover:var(--steel-blue-700);--background:var(--warm-neutral-50);--surface:#fff;--surface-light:var(--warm-neutral-100);--surface-elevated:#fff;--surface-muted:var(--warm-neutral-200);--text-primary:var(--concrete-gray-900);--text-secondary:var(--concrete-gray-700);--text-muted:var(--concrete-gray-600);--text-subtle:var(--concrete-gray-500);--text-inverse:#fff;--text-accent:var(--construction-blue-600);--border:var(--concrete-gray-200);--border-light:var(--warm-neutral-200);--border-soft:var(--concrete-gray-100);--border-focus:var(--construction-blue-400);--shadow-soft:0 1px 3px 0 rgba(37,99,235,.08);--shadow-gentle:0 2px 8px 0 rgba(37,99,235,.12);--shadow-elevated:0 4px 12px 0 rgba(37,99,235,.15);--shadow-large:0 8px 24px 0 rgba(37,99,235,.12);--success:var(--construction-green-600);--success-light:var(--construction-green-100);--warning:var(--safety-orange-600);--warning-light:var(--safety-orange-100);--error:#dc2626;--error-light:#fef2f2;--calc-bg:var(--surface);--calc-border:var(--concrete-industrial-200);--calc-input-bg:var(--concrete-gray-25);--calc-result-bg:var(--steel-blue-50);--calc-accent:var(--steel-blue-600);--calc-highlight:var(--construction-blue-600);--calc-surface:var(--concrete-gray-25);--calc-border-focus:var(--steel-blue-400);--radius:0.375rem;--radius-md:0.5rem;--radius-lg:0.75rem;--radius-xl:1rem;--radius-2xl:1.5rem;--spacing-xs:0.25rem;--spacing-sm:0.5rem;--spacing-md:0.75rem;--spacing-lg:1rem;--spacing-xl:1.5rem;--spacing-2xl:2rem;--spacing-3xl:3rem;--font-sans:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe 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0}.calculator-header{text-align:center;margin-bottom:3rem}.calculator-header h1{color:var(--steel-blue-700);font-size:2.5rem;font-weight:700;margin-bottom:1rem}.calculator-header p{color:var(--text-secondary);font-size:1.125rem;max-width:600px;margin:0 auto}.calculator-form{padding:2rem;max-width:500px;margin:0 auto 2rem}.input-with-unit{display:flex;gap:.75rem;align-items:center}.input-with-unit input{flex:2 1;min-width:0;padding:.75rem 1rem;border:2px solid var(--calc-border);border-radius:var(--radius-md);font-size:1rem;background:var(--calc-input-bg);color:var(--text-primary);transition:all .2s ease;font-weight:500}.input-with-unit input:focus{outline:none;border-color:var(--calc-border-focus);box-shadow:0 0 0 3px rgba(2,132,199,.1);background:var(--surface)}.input-with-unit select{flex:1 1;min-width:80px;max-width:100px;padding:.75rem .5rem;font-size:.875rem;cursor:pointer;font-weight:500}.calculator-form input,.calculator-form select,.calculator-form textarea,.input-with-unit 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100%)}.text-gradient{background:linear-gradient(135deg,var(--construction-blue-600),var(--construction-blue-800));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.btn-primary{background:var(--steel-blue-600);border:none;color:#fff;box-shadow:var(--shadow-md)}.btn-primary:hover{background:var(--steel-blue-700);box-shadow:var(--shadow-lg)}.guide-card,.tool-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-xl);transition:all .3s ease}.guide-card:hover,.tool-card:hover{box-shadow:var(--shadow-lg);transform:translateY(-4px);border-color:var(--construction-blue-300)}.calculator-page{background:var(--background)}.calculator-form{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-xl);box-shadow:var(--shadow-lg)}.calculate-btn{background:var(--steel-blue-600)}.results{background:var(--steel-blue-50);border:1px solid var(--steel-blue-200);border-radius:var(--radius-xl);box-shadow:var(--shadow-md)}.result-value{color:var(--steel-blue-700);font-weight:600}.calculators-page{background:var(--background);min-height:100vh}.page-header{text-align:center;margin-bottom:3rem}.page-header h1{color:var(--text-primary);font-size:2.5rem;font-weight:700;margin-bottom:1rem;background:linear-gradient(135deg,var(--construction-blue-600),var(--construction-blue-800));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.page-description{color:var(--text-secondary);font-size:1.125rem;max-width:600px;margin:0 auto}.tools-grid{max-width:1280px;margin:0 auto;padding:0 1rem}.category-section{margin-bottom:3rem}.category-title{color:var(--text-primary);font-size:1.875rem;font-weight:700;margin-bottom:1.5rem;padding-bottom:.5rem;border-bottom:2px solid var(--construction-blue-200)}.category-tools{display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));grid-gap:1.5rem;gap:1.5rem}.tool-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-xl);padding:1.5rem;transition:all .3s ease;text-decoration:none;color:inherit;display:block}.tool-card:hover{box-shadow:var(--shadow-lg);transform:translateY(-4px);border-color:var(--construction-blue-300)}.tool-icon{width:3rem;height:3rem;background:var(--construction-blue-100);border-radius:var(--radius-lg);display:flex;align-items:center;justify-content:center;margin-bottom:1rem}.tool-icon i{font-size:1.5rem;color:var(--construction-blue-600)}.tool-title{color:var(--text-primary);font-size:1.25rem;font-weight:600;margin-bottom:.5rem}.tool-description{color:var(--text-secondary);font-size:.875rem;line-height:1.5;margin:0}@media (max-width:768px){.category-tools{grid-template-columns:1fr}.page-header h1{font-size:2rem}.category-title{font-size:1.5rem}}.features-section{padding:5rem 0;background:linear-gradient(135deg,var(--concrete-gray-50) 0,var(--concrete-gray-100) 100%)}.features-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));grid-gap:2rem;gap:2rem;margin-top:3rem}.feature-item{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-xl);padding:2rem;text-align:center;transition:all .3s ease}.feature-item:hover{transform:translateY(-2px);box-shadow:var(--shadow-lg)}.feature-item .feature-icon{width:4rem;height:4rem;background:var(--construction-blue-100);border-radius:var(--radius-xl);display:flex;align-items:center;justify-content:center;margin:0 auto 1.5rem}.feature-item .feature-icon svg{width:2rem;height:2rem;color:var(--construction-blue-600)}.feature-item h3{color:var(--text-primary);font-size:1.25rem;font-weight:600;margin-bottom:1rem}.feature-item p{color:var(--text-secondary);font-size:.95rem;line-height:1.6;margin:0}.why-section{padding:5rem 0;background:var(--surface)}.why-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));grid-gap:2rem;gap:2rem;margin-top:3rem}.why-item{text-align:center;padding:2rem}.why-item.feature-icon{width:4rem;height:4rem;background:var(--construction-blue-100);border-radius:var(--radius-xl);display:flex;align-items:center;justify-content:center;margin:0 auto 1.5rem}.why-item.feature-icon svg{width:2rem;height:2rem;color:var(--construction-blue-600)}.why-item h3{color:var(--text-primary);font-size:1.25rem;font-weight:600;margin-bottom:1rem}.why-item p{color:var(--text-secondary);font-size:.95rem;line-height:1.6;margin:0}.seo-footer{padding:4rem 0 2rem;background:var(--concrete-gray-800);color:var(--concrete-gray-100)}.seo-content{max-width:1200px;margin:0 auto;padding:0 2rem}.seo-content h2{color:var(--concrete-gray-50);font-size:2rem;font-weight:700;margin-bottom:1rem;text-align:center}.seo-content>p{color:var(--concrete-gray-300);font-size:1.1rem;line-height:1.6;text-align:center;margin-bottom:3rem;max-width:800px;margin-left:auto;margin-right:auto}.seo-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));grid-gap:2rem;gap:2rem;margin-bottom:3rem}.seo-section h3{color:var(--concrete-gray-100);font-size:1.25rem;font-weight:600;margin-bottom:1rem}.seo-section ul{list-style:none;padding:0}.seo-section li{color:var(--concrete-gray-400);font-size:.95rem;margin-bottom:.5rem;padding-left:1rem;position:relative}.seo-section li:before{content:"•";color:var(--construction-blue-400);position:absolute;left:0}.app-category ul li,.benefit-item p,.seo-content .practice-item p,.seo-lead,.seo-section p{color:var(--text-inverse)!important}.seo-cta{display:flex;gap:1rem;justify-content:center;flex-wrap:wrap;margin-top:2rem}.seo-cta .btn-secondary{background:transparent;border:2px solid var(--construction-blue-400);color:var(--construction-blue-400)}.seo-cta .btn-secondary:hover{background:var(--construction-blue-400);color:var(--concrete-gray-900)}@media (max-width:768px){.features-grid,.why-grid{grid-template-columns:1fr;gap:1.5rem}.features-section,.why-section{padding:3rem 0}.feature-item,.why-item{padding:1.5rem}.seo-grid{grid-template-columns:1fr;gap:1.5rem}.seo-content h2{font-size:1.5rem}.seo-content>p{font-size:1rem}.seo-cta{flex-direction:column;align-items:center}}@media (max-width:480px){.features-grid,.why-grid{grid-template-columns:1fr}.feature-item .feature-icon,.why-item.feature-icon{width:3rem;height:3rem}.feature-item .feature-icon svg,.why-item.feature-icon svg{width:1.5rem;height:1.5rem}}