Safe navigation operator is a syntactic construct mostly found and used in programming languages that offer the object oriented programming paradigm. Safe navigation is needed when navigating properties/methods/children of an object with a need to ascertain that there are no broken pointers.
There is a common misconception in the web industry that frontend development is easy and has little or no use for algorithms and complex software concepts. This might be the most inaccurate perception for anyone to have. Building user interfaces is infact, exhaustive and can be more complex than backend sometimes.
The golden ratio is a math formula that exists in nature and have been adopted in designs since its discovery. There are patterns in natural objects including the sculpture of human looks that can be backed by this formula.