*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}:root{--color-bg: #ffffff;--color-bg-alt: #f8f9fa;--color-bg-card: #ffffff;--color-text: #1a1d23;--color-text-secondary: #6b7280;--color-text-muted: #9ca3af;--color-border: #e5e7eb;--color-border-light: #f3f4f6;--color-primary: #2563eb;--color-primary-hover: #1d4ed8;--color-primary-light: #eff6ff;--color-safe: #16a34a;--color-safe-bg: #f0fdf4;--color-safe-border: #bbf7d0;--color-caution: #ca8a04;--color-caution-bg: #fefce8;--color-caution-border: #fef08a;--color-danger: #dc2626;--color-danger-bg: #fef2f2;--color-danger-border: #fecaca;--color-accent-gradient: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);--font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;--font-mono: "SF Mono", "Cascadia Code", "Fira Code", monospace;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 16px;--shadow-sm: 0 1px 2px rgba(0, 0, 0, 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.15s}.alternative-item:hover{border-color:var(--color-primary);background:var(--color-primary-light)}.alternative-size{font-weight:600;font-variant-numeric:tabular-nums}.alternative-diff{font-size:.82rem;color:var(--color-text-secondary)}@keyframes fadeUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.fade-up{animation:fadeUp .4s ease-out forwards}.delay-1{animation-delay:.05s}.delay-2{animation-delay:.1s}.delay-3{animation-delay:.15s}.delay-4{animation-delay:.2s}@media(max-width:560px){.inputs-grid{grid-template-columns:1fr}.tabs{flex-wrap:wrap}.tab{flex:1 1 calc(50% - 2px);min-width:calc(50% - 2px)}.related-grid{grid-template-columns:1fr}.header-nav{gap:12px}.header-nav a{font-size:.82rem}h1{font-size:1.6rem}}@media(min-width:561px){.tools-grid{grid-template-columns:1fr 1fr}}.speedo-table{width:100%;border-collapse:collapse;margin-top:16px;font-size:.9rem}.speedo-table th,.speedo-table td{padding:8px 12px;border-bottom:1px solid var(--color-border-light);text-align:center;font-variant-numeric:tabular-nums}.speedo-table th{font-weight:600;color:var(--color-text-secondary);font-size:.82rem}.tooltip-trigger{display:inline-flex;align-items:center;justify-content:center;width:16px;height:16px;border-radius:50%;background:var(--color-border);color:var(--color-text-secondary);font-size:.65rem;font-weight:700;cursor:pointer;border:none;line-height:1}.tooltip-trigger:hover{background:var(--color-primary);color:#fff}.tooltip-bubble{position:absolute;bottom:calc(100% + 8px);left:50%;transform:translate(-50%);background:var(--color-text);color:#fff;padding:8px 12px;border-radius:var(--radius-sm);font-size:.8rem;font-weight:400;white-space:nowrap;max-width:260px;white-space:normal;z-index:10;line-height:1.4}.section-divider{width:100%;height:1px;background:var(--color-border-light);margin:48px 0 0}.specs-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:20px 0}.spec-card{background:var(--color-bg-alt);border-radius:var(--radius-md);padding:16px}.spec-card-label{font-size:.78rem;font-weight:600;color:var(--color-text-secondary);text-transform:uppercase;letter-spacing:.03em;margin-bottom:4px}.spec-card-value{font-size:1.2rem;font-weight:700;font-variant-numeric:tabular-nums}.size-hero{display:flex;align-items:center;gap:24px;margin-bottom:32px}.size-hero-visual{flex-shrink:0}.size-hero-info{flex:1}.pro-calculator{margin-top:48px;padding-top:32px;border-top:2px solid var(--color-border)}.pro-header{margin-bottom:24px}.pro-title{font-size:1.5rem;font-weight:800;color:var(--color-text);margin-bottom:4px;background:var(--color-accent-gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.pro-subtitle{font-size:.9rem;color:var(--color-text-secondary)}.pro-tabs{display:flex;gap:4px;overflow-x:auto;-webkit-overflow-scrolling:touch;padding-bottom:4px;margin-bottom:20px}.pro-tab{padding:8px 16px;border:1px solid var(--color-border);background:var(--color-bg);border-radius:var(--radius-sm);font-size:.85rem;font-weight:500;color:var(--color-text-secondary);cursor:pointer;white-space:nowrap;transition:all .15s}.pro-tab:hover{background:var(--color-bg-alt)}.pro-tab.active{background:var(--color-primary);color:#fff;border-color:var(--color-primary)}.pro-scenario-desc{padding:12px 16px;background:var(--color-primary-light);border-radius:var(--radius-sm);font-size:.88rem;color:var(--color-text);margin-bottom:20px;border-left:3px solid var(--color-primary)}.pro-section{margin-bottom:24px;padding:20px;background:var(--color-bg-card);border:1px solid var(--color-border-light);border-radius:var(--radius-md)}.pro-section-title{font-size:1rem;font-weight:700;color:var(--color-text);margin-bottom:12px}.pro-impact-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.pro-impact-card{padding:12px;background:var(--color-bg-alt);border-radius:var(--radius-sm)}.pro-impact-label{font-size:.82rem;font-weight:600;color:var(--color-text-secondary);margin-bottom:6px}.pro-impact-bar{height:6px;background:#e5e7eb;border-radius:3px;overflow:hidden;margin-bottom:4px}.pro-impact-fill{height:100%;border-radius:3px;transition:width .3s}.pro-impact-note{font-size:.78rem;color:var(--color-text-muted)}.btn-sm{padding:4px 10px;font-size:.8rem}@media(max-width:640px){.pro-impact-grid{grid-template-columns:1fr}.pro-tabs{gap:2px}.pro-tab{padding:6px 10px;font-size:.8rem}.pro-section{padding:14px}.size-hero{flex-direction:column}}