UK homewares retailer Dunelm delivered a upbeat outlook on Thursday after increasing sales by 10.7% in the third quarter, though growth did tail off slightly from the first half.The company also warned that meeting its full-year targets will depend on how trading will fare over the "volatile" summer period.Sales totalled £216.2m in the 13 weeks ended 28 March, up £20.9m on the same point last year. On a like-for-like (LFL) basis, which includes home delivery but excludes new stores, sales were up 4.9% at £190.3m.However, this was down from the 6.2% LFL growth seen in the first six months of the financial year due to stronger comparatives in the third quarter."We have recorded solid sales growth over the last quarter, and we believe that we have continued to take market share on a like-for-like basis," said chief executive Will Adderley.He expressed optimism about Dunelm's current Easter trading period and upcoming summer sale, as well as the launch of its new web platform before the end of the financial year. These factors are all expected to "drive further sales growth through our final quarter"."However, the full-year outcome against our ambitious internal targets will ultimately depend on the traditionally volatile summer months' trading," Adderley said.Dunelm opened two new stores during the period, taking the total superstore openings this financial year to eight, including one relocation. These generated sales of £26m over the third quarter alone.A further four stores are expected to open before the year-end, taking the portfolio to 148 as the retailer continues on its way to its medium-term target of 200.The stock was up 0.2% at 854.5p in early deals.