*{box-sizing:border-box;margin:0;padding:0}body{background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);justify-content:center;align-items:center;min-height:100vh;font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;display:flex}.login-container{background:#fff;border-radius:10px;width:100%;max-width:400px;padding:40px;box-shadow:0 10px 25px #0003}h1{text-align:center;color:#333;margin-bottom:30px;font-size:28px}.form-group{margin-bottom:20px}label{color:#555;margin-bottom:8px;font-weight:500;display:block}input[type=text],input[type=password]{border:1px solid #ddd;border-radius:5px;width:100%;padding:12px;font-size:14px;transition:border-color .3s}input[type=text]:focus,input[type=password]:focus{border-color:#667eea;outline:none;box-shadow:0 0 0 3px #667eea1a}button{color:#fff;cursor:pointer;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);border:none;border-radius:5px;width:100%;padding:12px;font-size:16px;font-weight:600;transition:transform .2s,box-shadow .2s}button:hover{transform:translateY(-2px);box-shadow:0 5px 15px #667eea66}button:active{transform:translateY(0)}.error{color:#c33;background:#fee;border-left:4px solid #c33;border-radius:5px;margin-bottom:20px;padding:12px}