:root{--bg-page:#f9fafb;--bg-surface:#fff;--text-primary:#111827;--text-secondary:#4b5563;--text-tertiary:#9ca3af;--primary-color:#2563eb;--primary-hover:#1d4ed8;--primary-light:#eff6ff;--border-color:#e5e7eb;--shadow-sm:0 1px 2px 0 rgba(0,0,0,.05);--shadow-md:0 4px 6px -1px rgba(0,0,0,.1),0 2px 4px -1px rgba(0,0,0,.06);--shadow-lg:0 10px 15px -3px rgba(0,0,0,.1),0 4px 6px -2px rgba(0,0,0,.05);--radius-sm:6px;--radius-md:8px;--radius-lg:12px}*{box-sizing:border-box;margin:0;padding:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;background-color:var(--bg-page);color:var(--text-primary);line-height:1.6;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none;transition:color .2s ease}.container{max-width:1200px;margin:0 auto;padding:0 24px}nav{background:hsla(0,0%,100%,.9);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-bottom:1px solid var(--border-color);position:-webkit-sticky;position:sticky;top:0;z-index:100}