Casual day notwithstanding, the loudly proclaimed relaxed changes in acceptability are more fashion fantasy than business fact. The only bank accounts that are fattened by a new fad are those of the designer and manufacturer who created it. Ladies avoid heavy doses of pastels - Women can add authority by wearing less pink, baby blue, and other pastels that are equated with nurseries. There is also little or no authority to be found in dangle earrings, sexy shoes, and ankle bracelets. Also, do not wear stockings with overly fussy patterns.
Lace is definitely out, as are seams.
As a fall back, bring an extra pair of panty hose in your handbag just in case you get a run. Get your hands on an annual report - If the company is publicly traded, call the Investor Relations Department and obtain an annual report. Look at the pictures inside, this is how senior management wants the shareholders to perceive that they dress everyday. Copy the styles in the pictures and you can't go wrong. When it comes to shoes, handbags, and belts, don't sacrifice quality for quantity.