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1rem;border-radius:4px;background-color:rgba(220,53,69,.1);border-left:4px solid var(--error-color);color:var(--error-color)}.error-message p{margin:0}.footer{margin-top:2rem;text-align:center;padding:1rem;border-top:1px solid var(--border-color);font-size:.9rem;color:var(--secondary-color)}:focus-visible{outline:2px solid var(--primary-color);outline-offset:2px}@media(max-width:480px){button{width:100%}.input-actions,.output-actions{flex-direction:column;width:100%}.action-button,.file-upload-button{width:100%;text-align:center}}@media print{.base64-decoder{padding:0;box-shadow:none}.header{border-bottom:1px solid #000}.controls,.input-actions,.output-actions,.theme-toggle{display:none}textarea{border:1px solid #000}}