TODO

[x] INFORMATION & OPTIONS:
    [x] Make header and footer responsive.
    [x] Add attribution and GitHub link in the footer.
    [x] Add the instructions and the pay table buttons in the footer.
    [x] Add pay table with horizontal scroll on narrow screens.
    [x] Allow enable/disable sound and vibration.
    [x] Hide vibration button on desktop.
    [x] Automatically show instructions the first time.
    [x] Start playing automatically when closing the instructions the first time.
    [ ] Add speed controls (and link sound rate to speed).

[x] TECH DEBT:
    [x] Separate components in different files.
    [x] Update dependencies and setup.
    [x] Play sounds using the WebAudio API.
    [ ] Add support for autobind decorator and coalescence operators.
    [ ] Add a ServiceWorker.
    [ ] **Replace listener properties with addEventListener.**
    [ ] **Pass component params as options object.**
    [ ] **Handle code TODOs.**
    [ ] Automatically enable/disable zoom and fix performance issue with it.
    [ ] Show info about https://stackoverflow.com/questions/47459812/javascript-new-audio-throw-not-implemented-on-window-10-n-on-ie11-and-edge
    [ ] Add tests.
    [ ] Measure FPS and adjust quality/features automatically.


[x] UI:
    [x] Create a logo.
    [x] Add a new Modal and ModalButton components.
    [x] Fix shadows on Firefox looking larger.
    [x] Highlight winning combinations (with a different shadow color).
    [x] Focus/Hover styles for buttons, etc.
    [x] Update logo to have vertical "speed" stripes.
    [ ] **Adjust breakpoints when all controls are visible.**
    [ ] **Disable pay table tabs/buttons if larger viewport. Use media query listener rather than resize listener.**
    [ ] Animate logo and icons when updated/hovered.
    [ ] Show a message to non-supported browsers.


[x] GAME FUNCTIONALITY & FEATURES:
    [x] Prevent holding down space/enter so fast.
    [x] Remove the focus when using the footer buttons, links or the close buttons in the modals.
    [ ] Add support for images/sprites.
    [ ] Improve cheat mode.
    [ ] 3D effects/animations.