*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;background:#f5f7fa}.app-wrapper{min-height:100vh;display:flex;flex-direction:column}.main-content{flex:1;padding-bottom:64px}.bottom-nav{position:fixed;bottom:0;left:0;right:0;display:flex;justify-content:space-around;align-items:center;height:60px;background:#fff;border-top:1px solid #eee;z-index:100}.nav-item{display:flex;flex-direction:column;align-items:center;gap:2px;cursor:pointer;padding:4px 12px}.nav-icon{font-size:20px;opacity:.6;transition:opacity .2s}.nav-label{font-size:11px;color:#999;transition:color .2s}.nav-item.active .nav-icon{opacity:1}.nav-item.active .nav-label{color:#667eea;font-weight:500}