//@version=3
study (title = "Opening Range", overlay = true)
timeframe = input (title = "Timeframe", type = resolution, defval = "240")
high_level = security (ticker, timeframe, high, barmerge.gaps_off, barmerge.lookahead_on)
low_level = security (ticker, timeframe, low, barmerge.gaps_off, barmerge.lookahead_on)

first_level = security (ticker, timeframe, time, barmerge.gaps_off, barmerge.lookahead_on)
last_level = security (ticker, timeframe, valuewhen (barstate.islast, time, 0), barmerge.gaps_off, barmerge.lookahead_on)
last_day = first_level >= last_level

plot (last_day ? high_level : na, title = "High", color = red, transp = 0)
plot (last_day ? low_level : na, title = "Low", color = green, transp = 0)