*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Helvetica Neue,sans-serif;background:#f5f5f5;min-height:100vh;padding:0;color:#333}.main-nav{background:#000;color:#fff;padding:0 20px;box-shadow:0 2px 4px #0000001a}.nav-content{max-width:1600px;margin:0 auto;display:flex;align-items:center;justify-content:space-between;height:60px}.nav-title{font-size:1.25rem;font-weight:600;margin:0}.nav-links{display:flex;gap:20px}.nav-link{color:#fff;text-decoration:none;padding:8px 16px;border-radius:4px;transition:background-color .2s ease;font-weight:500}.nav-link:hover{background:#ffffff1a}.nav-link.active{background:#fff3}.page{display:none;min-height:calc(100vh - 60px);padding:20px}.page.active{display:block}iframe{flex:1;width:100%;border:none;background:#fff}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:#f5f5f5}::-webkit-scrollbar-thumb{background:#cbd5e0;border-radius:4px}::-webkit-scrollbar-thumb:hover{background:#a0aec0}@media (max-width: 768px){body{padding:0}.main-nav{padding:0 10px}.nav-content{height:50px}.nav-title{font-size:1rem}.nav-links{gap:10px}.nav-link{padding:6px 12px;font-size:.9rem}.page{padding:10px}}