.app{max-width:1200px;margin:0 auto;padding:20px;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif}.header{text-align:center}.header h1{color:#333;margin-bottom:10px}.header p{color:#666;font-size:16px}.tabs{display:flex;gap:10px;margin-bottom:30px;border-bottom:2px solid #e0e0e0}.tab{padding:12px 24px;background:none;border:none;border-bottom:3px solid transparent;cursor:pointer;font-size:16px;color:#666;transition:all .3s}.tab:hover{color:#333}.tab.active{color:#1890ff;border-bottom-color:#1890ff}.content{min-height:400px}