The calendar width must be calculated as exactly 7 columns plus 10px paddings using SCSS variables, but here you hardcode max-width: 800px and don’t base it on the cell size, border, gap, and padding variables as required ("Don't use hardcoded px values if they are used several times" and "Use properly named variables to make all the calculations more clear").

The task states all hover changes (transform and background color) must be animated with duration 0.5s, but this transition only animates transform and not background-color, and uses 500ms without including background-color. Consider adding background-color to the transition and ensuring the duration matches 0.5s.

According to the description, styles must be written in src/styles/main.scss instead of src/style.css, and your HTML should link that file. Right now you link styles/index.scss, so you need to move the styles into main.scss and update this href accordingly.

The requirements say: "Write styles in src/styles/main.scss instead of src/style.css" and also "Use properly named variables to make all the calculations more clear". Here you’re using index.scss and not using variables for shared values (day size, border, gap, padding), so consider moving this file to main.scss and introducing SCSS variables for these repeated px values.

The calendar width must be limited to exactly 7 columns + 10px paddings, and the description asks not to hardcode px values used several times but to use variables for clearer calculations. max-width: 800px; is a magic number; instead, derive the width from the day size, border, gap, and padding using SCSS variables.

This violates the requirement "Don't use hardcoded px values if they are used several times" and "Use properly named variables to make all the calculations more clear". gap: 1px; is used here and combined in other calculations, so it should be represented via a SCSS variable rather than repeated raw values.

Padding is part of the "width = 7 columns + 10px paddings" requirement and is also a repeated px value. Instead of hardcoding 10px here, define a SCSS variable (e.g. $calendar-padding) and use it consistently when computing width and layout.

The hover behavior is required to animate all changes (movement and color) over 0.5s. Here transition: transform 500ms; only animates transform. Consider transitioning both transform and background-color (and using 0.5s as the duration) to fully satisfy the hover animation requirement.

The spec states "On hovering over a cell: cursor should become pointer", meaning the cursor change should be part of the hover state. Currently cursor: pointer; is set on the base .calendar__day, so the cursor is always a pointer even when not hovering. Move the cursor declaration to the :hover rule to match the requirement.

This margin-left calculation uses hardcoded 100px and 1px, which are also used as width, height, and gap elsewhere. The description forbids repeating such hardcoded px values and asks for named variables. Introduce SCSS variables (e.g. $day-size, $day-border, $day-gap) and use them here so the start-day offset stays consistent with the actual cell dimensions.

The task requires limiting calendar width to "exactly 7 columns + 10px paddings" and avoiding repeated hardcoded px values. Here $calendar__width: 800px; is a magic number not derived from $day__width, $days__gap, and $paddings, which violates that requirement; consider computing this width from those variables instead.

height: 100px; repeats the day size as a literal while you already have $day__width. The description says not to use hardcoded px values when reused; consider using a variable (e.g. $day__size) for both width and height so each day is a 100px square driven by SCSS variables.

This margin-left uses hardcoded 100px and 1px instead of $day__width and $days__gap. The requirements explicitly say to avoid hardcoded px values used several times and to use variables for all calculations (including the 7 columns + 10px paddings and start-day offsets). Refactor this expression to rely on your SCSS variables, not raw literals.

The task requires the calendar width to be "exactly 7 columns + 10px paddings" and asks not to reuse hardcoded px values. max-width: $calendar__count * ($day__width + $paddings); adds $paddings per column instead of a single padding value for the whole block, so changing $day__width or $days__gap will not correctly keep "7 columns + 10px paddings". Consider computing width from 7 * $day__width, 6 * $days__gap, and a single horizontal padding value as per the description.

With padding-left: $paddings; only, the calendar gets padding on one side, while the requirement talks about 10px paddings (plural). Together with the current max-width formula, this prevents the layout from truly reflecting "exactly 7 columns + 10px paddings". Consider applying padding symmetrically and updating the width calculation so that modifiers and size variables correctly control the layout as required by checklist item "Changing 'month-lengh' and 'start-day' modifier in the code element reflects in changing calendar layout".

Your max-width calculation max-width: $calendar__count * ($day__width + $paddings); does not match the requirement "limit its width to exactly 7 columns + 10px paddings" and the previous correction about deriving width from size variables. Padding is being added per column here instead of once for the container, and the 1px gap between cells is not included in the formula. Consider deriving a dedicated $calendar__width from the variables as 7 * $day__width + 6 * $days__gap + 2 * $paddings and using that, so changing day__width, days__gap, or paddings keeps the layout consistent.
This is related to the generalized requirement: "Derive $calendar__width from size variables instead of using a hardcoded 800px, so the calendar width matches ‘exactly 7 columns + 10px paddings’ and updates correctly when day size or gap variables change."

You introduced $day__height: 100px; as a separate literal, but the previous correction explicitly required replacing height: 100px; with a variable-based expression tied to the day size (e.g. using $day__width or a dedicated $day__size variable). Right now, changing $day__width will not automatically keep the cells square. To meet the requirement "Don’t use hardcoded px values if they are used several times" and the previous review note, consider either removing $day__height and using height: $day__width; or defining a single $day__size variable used for both width and height.
This still violates the generalized correction: "Replace height: 100px; on .calendar__day with a variable-based expression (e.g., using $day__width or a $day__size variable) so each day is a true square controlled by SCSS variables."