body{background:#fff;color:#000;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol"}:root{--header-bg: #ffffff;--header-text: #1f2937;--header-link: #4b5563;--header-link-hover: #3b82f6;--header-active: #3b82f6;--border-color: #e5e7eb;--container-max-width: 1200px;--header-padding: 1rem}.site-header{background-color:var(--header-bg);border-bottom:1px solid var(--border-color);position:sticky;top:0;z-index:100;padding:var(--header-padding) 0}.container{max-width:var(--container-max-width);margin:0 auto;padding:0 1.5rem;display:flex;flex-direction:column;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:1rem}.site-brand{flex-shrink:0}.site-title{font-size:2rem;font-weight:700;text-decoration:none;color:var(--header-text);transition:color 0.2s ease}.site-title:hover{color:var(--header-link-hover)}.site-nav{display:flex}.nav-list{display:flex;list-style:none;margin:0;padding:0;gap:2rem}.nav-link{text-decoration:none;color:var(--header-link);font-weight:500;transition:color 0.2s ease;padding:0.5rem 0;position:relative}.nav-link:hover,.nav-link.active{color:var(--header-active)}.nav-link.active::after{content:'';position:absolute;bottom:0;left:0;width:100%;height:2px;background-color:var(--header-active);border-radius:2px}