Certaines images très petites vont demander un transform:scale très élevé.
Par conséquent, il faudra jouer avec les margin left et top pour recentrer. Si vous avez des idées d'overlay qui peuvent être amusant, dites-le en commentaire. Mettez directement le lien de l'image si vous l'avez (sinon je chercherai par moi-même).

Je n'ai pas mis les codes car c'est différent pour chaque image et dans le cas où vous avez déjà des images mis en game_header.
Sous chaque image, retrouvez le lien. (j'ai fait des exemples en dessous pour vous donner une idée de comment faire)

https://static.vecteezy.com/system/resources/thumbnails/018/972/644/small_2x/abstract-colorful-gradient-light-leak-overlay-png.png	https://static.vecteezy.com/system/resources/previews/015/723/405/non_2x/window-shadow-overlay-effect-free-png.png
https://static.vecteezy.com/system/resources/previews/015/723/303/non_2x/window-shadow-overlay-effect-free-png.png	https://static.vecteezy.com/system/resources/previews/015/723/175/non_2x/window-shadow-overlay-effect-free-png.png" alt="fenetre ronde et feuilles
https://i.pinimg.com/originals/54/d0/16/54d016db5827e726f57280fef46c4928.gif	https://png.pngtree.com/png-vector/20240530/ourmid/pngtree-mesmerizing-blend-of-blurred-lights-overlaid-bokeh-and-blue-glow-with-png-image_12354824.png
https://static.vecteezy.com/system/resources/thumbnails/016/586/628/small/twinkle-golden-star-pattern-for-photo-effect-and-overlay-abstract-blurry-star-light-texture-for-background-png.png	https://i.pinimg.com/originals/da/bc/34/dabc34d1b933e4fd856776056cae7c55.gif
https://i.pinimg.com/originals/f5/39/45/f539451fcdcdc707e1bef4f7d0131b2f.gif	https://i.pinimg.com/originals/ca/2c/b6/ca2cb65c5e194793ea50ee3fc21328ed.gif
https://i.pinimg.com/originals/69/e2/7c/69e27c177766a3cb153b37682b22186c.gif	https://i.pinimg.com/originals/3d/29/ad/3d29ad10f52599fcee7c17d3fbba4fec.gif
https://i.pinimg.com/originals/88/05/7d/88057d002bba3a6c578f8ee353a608db.gif	https://i.pinimg.com/originals/a9/54/7b/a9547bb2bc381709d071b75f97920a56.gif
https://i.pinimg.com/originals/2e/ee/a8/2eeea803b04768c45c4f5a78f2cbbd8b.gif	https://i.pinimg.com/originals/b3/b4/8a/b3b48a35785465ed53f20d332f191a5c.gif
https://i.pinimg.com/originals/49/d6/c9/49d6c9c45642db999c19257aa074adc5.gif	https://i.pinimg.com/originals/04/bc/7f/04bc7f069cc50f7b7d1c50fc9d70136a.gif
https://i.pinimg.com/originals/dd/bc/91/ddbc91d26f6d549f2ee3caa918ba6060.gif	https://i.ibb.co/fq77nR7/bordurebleu.png
https://images-wixmp-ed30a86b8c4ca887773594c2.wixmp.com/f/4a6fdcaa-e52c-4e29-8e52-1a689a6fe632/dfnepva-94313ab6-9c1c-47f0-bb7f-1df69a8a5623.png?token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ1cm46YXBwOjdlMGQxODg5ODIyNjQzNzNhNWYwZDQxNWVhMGQyNmUwIiwiaXNzIjoidXJuOmFwcDo3ZTBkMTg4OTgyMjY0MzczYTVmMGQ0MTVlYTBkMjZlMCIsIm9iaiI6W1t7InBhdGgiOiJcL2ZcLzRhNmZkY2FhLWU1MmMtNGUyOS04ZTUyLTFhNjg5YTZmZTYzMlwvZGZuZXB2YS05NDMxM2FiNi05YzFjLTQ3ZjAtYmI3Zi0xZGY2OWE4YTU2MjMucG5nIn1dXSwiYXVkIjpbInVybjpzZXJ2aWNlOmZpbGUuZG93bmxvYWQiXX0.pGoAComaFi2CnM_fNNhsqfbGBdrLwTVTuG9Z4HBzY5I	https://images-wixmp-ed30a86b8c4ca887773594c2.wixmp.com/f/4a6fdcaa-e52c-4e29-8e52-1a689a6fe632/dfnepv8-3b9a9d3c-b827-4860-a58e-b260f47d782c.png?token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ1cm46YXBwOjdlMGQxODg5ODIyNjQzNzNhNWYwZDQxNWVhMGQyNmUwIiwiaXNzIjoidXJuOmFwcDo3ZTBkMTg4OTgyMjY0MzczYTVmMGQ0MTVlYTBkMjZlMCIsIm9iaiI6W1t7InBhdGgiOiJcL2ZcLzRhNmZkY2FhLWU1MmMtNGUyOS04ZTUyLTFhNjg5YTZmZTYzMlwvZGZuZXB2OC0zYjlhOWQzYy1iODI3LTQ4NjAtYTU4ZS1iMjYwZjQ3ZDc4MmMucG5nIn1dXSwiYXVkIjpbInVybjpzZXJ2aWNlOmZpbGUuZG93bmxvYWQiXX0.H8I4sXhZkLNnYjJZoxiDeONxny7kV6aZTY-gqV8O1Aw
https://static.vecteezy.com/system/resources/thumbnails/047/601/211/small_2x/yellow-light-transition-overlay-cut-out-stock-png.png	https://static.vecteezy.com/system/resources/previews/042/725/802/non_2x/shadow-tree-branches-sunlight-shade-on-transparent-backgrounds-3d-rendering-free-png.png

Quelques Exemples avec couleurs et/ou overlay

Bordure vert

<div id="game_header" style="top: 0;"> <div style="position: absolute; height: 1400px; box-shadow: 0 0 1px 300px #82BF44; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie"></div> <div style="position: absolute; height: 1200px; box-shadow: 0 0 1px 300px #82BF44; width: 1px; margin-top: 210px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" src="src" mce_src="src" alt="couleurunie"></div> </div>

 

Bordure rouge foncé

<div id="game_header" style="top: 0;"> <div style="position: absolute; height: 1400px; box-shadow: 0 0 1px 300px #610C04; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie"></div> <div style="position: absolute; height: 1200px; box-shadow: 0 0 1px 300px #610C04; width: 1px; margin-top: 210px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" src="src" mce_src="src" alt="couleurunie"></div> </div></div> </div>

 

Bordure ciel ciel

<div id="game_header" style="top: 0;"> <div style="position: absolute; height: 1400px; box-shadow: 0 0 1px 300px #ADD8E6; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie"></div> <div style="position: absolute; height: 1200px; box-shadow: 0 0 1px 300px #ADD8E6; width: 1px; margin-top: 210px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" src="src" mce_src="src" alt="couleurunie"></div> </div>

 

Bordure violet

<div id="game_header" style="top: 0;"> <div style="position: absolute; height: 1400px; box-shadow: 0 0 1px 300px #936687; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie"></div> <div style="position: absolute; height: 1200px; box-shadow: 0 0 1px 300px #936687; width: 1px; margin-top: 210px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" src="src" mce_src="src" alt="couleurunie"></div> </div>

 

Bordure jaune

<div id="game_header" style="top: 0;"> <div style="position: absolute; height: 1400px; box-shadow: 0 0 1px 300px #ffdb58; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie"></div> <div style="position: absolute; height: 1200px; box-shadow: 0 0 1px 300px #ffdb58; width: 1px; margin-top: 210px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" src="src" mce_src="src" alt="couleurunie"></div> </div>

 

Bordure jaune + bokeh

<div id="game_header" style="top: 0;"><div style="height: 1400px; box-shadow: 0 0 1px 300px #ffdb58; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="height: 1200px; box-shadow: 0 0 1px 300px #ffdb58; width: 1px; margin-top: -1070px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="width: 100%; pointer-events: none; margin-top: -1350px;"><img style="transform: scale(4.3) rotate(-90deg); margin-left: -80px; filter: contrast(200%);" mce_style="transform: scale(4.3) rotate(-90deg); margin-left: -80px; filter: contrast(200%);" src="https://png.pngtree.com/png-vector/20240530/ourmid/pngtree-mesmerizing-blend-of-blurred-lights-overlaid-bokeh-and-blue-glow-with-png-image_12354824.png" mce_src="https://png.pngtree.com/png-vector/20240530/ourmid/pngtree-mesmerizing-blend-of-blurred-lights-overlaid-bokeh-and-blue-glow-with-png-image_12354824.png" alt="eclat lumiere" /></div> </div>

 

Bordure rose bonbon

<div id="game_header" style="top: 0;"> <div style="position: absolute; height: 1400px; box-shadow: 0 0 1px 300px #F9429E; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie"></div> <div style="position: absolute; height: 1200px; box-shadow: 0 0 1px 300px #F9429E; width: 1px; margin-top: 210px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -380px;" src="src" mce_src="src" alt="couleurunie"></div> </div>

 

Bordure rose bonbon + lumière jaune rose

<div id="game_header" style="top: 0;"> <div style="height: 1400px; box-shadow: 0 0 1px 300px #F9429E; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="height: 1200px; box-shadow: 0 0 1px 300px #F9429E; width: 1px; margin-top: -1070px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="height: 1200px; width: 100%; pointer-events: none; margin-top: -1080px;"><img style="transform: scale(3.3); margin-left: 150px;" mce_style="transform: scale(3.3); margin-left: 150px;" src="https://static.vecteezy.com/system/resources/thumbnails/018/972/644/small_2x/abstract-colorful-gradient-light-leak-overlay-png.png" mce_src="https://static.vecteezy.com/system/resources/thumbnails/018/972/644/small_2x/abstract-colorful-gradient-light-leak-overlay-png.png" alt="lumi rose" /></div> </div>

 

Bordure gris + ombre arbre + pluie (animé)

<div id="game_header" style="top: 0;"> <div style="height: 1400px; box-shadow: 0 0 1px 300px #717c72; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="height: 1200px; box-shadow: 0 0 1px 300px #717c72; width: 1px; margin-top: -1070px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="height: 1200px; width: 100%; margin-top: -1550px; pointer-events: none; opacity: 50%;"><img style="transform: scale(1.3); margin-left: -400px;" mce_style="transform: scale(1.3); margin-left: -400px;" src="https://static.vecteezy.com/system/resources/previews/042/725/802/non_2x/shadow-tree-branches-sunlight-shade-on-transparent-backgrounds-3d-rendering-free-png.png" mce_src="https://static.vecteezy.com/system/resources/previews/042/725/802/non_2x/shadow-tree-branches-sunlight-shade-on-transparent-backgrounds-3d-rendering-free-png.png" alt="arbre ombre" /></div> <div style="height: 1200px; width: 100%; margin-top: -1050px; pointer-events: none; opacity: 50%;"><img style="transform: scale(1.5); margin-left: -310px;" mce_style="transform: scale(1.5); margin-left: -310px;" src="https://i.pinimg.com/originals/04/bc/7f/04bc7f069cc50f7b7d1c50fc9d70136a.gif" mce_src="https://i.pinimg.com/originals/04/bc/7f/04bc7f069cc50f7b7d1c50fc9d70136a.gif" alt="pluie" /></div> </div>

 

Feuilles (animé)

<div id="game_header" style="top: 0;"> <div style="width: 100%; pointer-events: none; margin-top: 276px;"><img style="transform: scale(2);" mce_style="transform: scale(2);" src="https://i.pinimg.com/originals/f5/39/45/f539451fcdcdc707e1bef4f7d0131b2f.gif" mce_src="https://i.pinimg.com/originals/f5/39/45/f539451fcdcdc707e1bef4f7d0131b2f.gif" alt="feuilles tombantes" /></div> </div>

 

Fenetre ronde

<div id="game_header" style="top: 0;"> <div style="width: 100%; pointer-events: none; margin-top: 270px; opacity: 60%;"><img style="margin-left: -500px; transform: scale(1.5);" mce_style="margin-left: -500px; transform: scale(1.5);" src="https://static.vecteezy.com/system/resources/previews/015/723/175/non_2x/window-shadow-overlay-effect-free-png.png" mce_src="https://static.vecteezy.com/system/resources/previews/015/723/175/non_2x/window-shadow-overlay-effect-free-png.png" alt="fenetre ronde et feuilles" /></div> </div>

 

Rayons du soleil

<div id="game_header" style="top: 0;"> <div style="width: 100%; pointer-events: none; margin-top: 150px; opacity: 60%;"><img style="transform: scale(1.6); margin-left: -35px;" mce_style="transform: scale(1.6); margin-left: -35px;" src="https://static.vecteezy.com/system/resources/thumbnails/047/601/211/small_2x/yellow-light-transition-overlay-cut-out-stock-png.png" mce_src="https://static.vecteezy.com/system/resources/thumbnails/047/601/211/small_2x/yellow-light-transition-overlay-cut-out-stock-png.png" alt="soleil flamboyant" /></div> </div>

 

Lumière bleu haut

<div id="game_header" style="top: 0;"> <div style="width: 100%; pointer-events: none; margin-top: 230px; opacity: 80%;"><img style="margin-left: -400px; transform: scale(1.5);" mce_style="margin-left: -400px; transform: scale(1.5);" src="https://images-wixmp-ed30a86b8c4ca887773594c2.wixmp.com/f/4a6fdcaa-e52c-4e29-8e52-1a689a6fe632/dfnepva-94313ab6-9c1c-47f0-bb7f-1df69a8a5623.png?token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ1cm46YXBwOjdlMGQxODg5ODIyNjQzNzNhNWYwZDQxNWVhMGQyNmUwIiwiaXNzIjoidXJuOmFwcDo3ZTBkMTg4OTgyMjY0MzczYTVmMGQ0MTVlYTBkMjZlMCIsIm9iaiI6W1t7InBhdGgiOiJcL2ZcLzRhNmZkY2FhLWU1MmMtNGUyOS04ZTUyLTFhNjg5YTZmZTYzMlwvZGZuZXB2YS05NDMxM2FiNi05YzFjLTQ3ZjAtYmI3Zi0xZGY2OWE4YTU2MjMucG5nIn1dXSwiYXVkIjpbInVybjpzZXJ2aWNlOmZpbGUuZG93bmxvYWQiXX0.pGoAComaFi2CnM_fNNhsqfbGBdrLwTVTuG9Z4HBzY5I" mce_src="https://images-wixmp-ed30a86b8c4ca887773594c2.wixmp.com/f/4a6fdcaa-e52c-4e29-8e52-1a689a6fe632/dfnepva-94313ab6-9c1c-47f0-bb7f-1df69a8a5623.png?token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ1cm46YXBwOjdlMGQxODg5ODIyNjQzNzNhNWYwZDQxNWVhMGQyNmUwIiwiaXNzIjoidXJuOmFwcDo3ZTBkMTg4OTgyMjY0MzczYTVmMGQ0MTVlYTBkMjZlMCIsIm9iaiI6W1t7InBhdGgiOiJcL2ZcLzRhNmZkY2FhLWU1MmMtNGUyOS04ZTUyLTFhNjg5YTZmZTYzMlwvZGZuZXB2YS05NDMxM2FiNi05YzFjLTQ3ZjAtYmI3Zi0xZGY2OWE4YTU2MjMucG5nIn1dXSwiYXVkIjpbInVybjpzZXJ2aWNlOmZpbGUuZG93bmxvYWQiXX0.pGoAComaFi2CnM_fNNhsqfbGBdrLwTVTuG9Z4HBzY5I" alt="lumiere bleu" /></div> </div>

 

Papillons (animé)

<div id="game_header" style="top: 0;"> <div style="width: 100%; pointer-events: none; margin-top: 80px;"><img style="margin-left: -580px; transform: scale(1.3);" mce_style="margin-left: -580px; transform: scale(1.3);" src="https://i.pinimg.com/originals/88/05/7d/88057d002bba3a6c578f8ee353a608db.gif" mce_src="https://i.pinimg.com/originals/88/05/7d/88057d002bba3a6c578f8ee353a608db.gif" alt="papillons" /><img style="margin-left: 1040px; transform: scale(1.3) scaleX(-1);" mce_style="margin-left: 1040px; transform: scale(1.3) scaleX(-1);" src="https://i.pinimg.com/originals/88/05/7d/88057d002bba3a6c578f8ee353a608db.gif" mce_src="https://i.pinimg.com/originals/88/05/7d/88057d002bba3a6c578f8ee353a608db.gif" alt="papillons" /></div> </div>

 

Neige / étoiles brillantes (animé)

<div id="game_header" style="top: 0;"> <div style="width: 100%; pointer-events: none; margin-top: 280px;"><img style="transform: scale(1.6); margin-left: -60px;" mce_style="transform: scale(1.6); margin-left: -60px;" src="https://i.pinimg.com/originals/69/e2/7c/69e27c177766a3cb153b37682b22186c.gif" mce_src="https://i.pinimg.com/originals/69/e2/7c/69e27c177766a3cb153b37682b22186c.gif" alt="eclat brille discret" /></div> </div>

 

Rose + ombres + pixel (animé)

<div id="game_header" style="top: 0;"> <div style="height: 1400px; box-shadow: 0 0 1px 300px #FFC1B4; width: 1px; margin-left: -533px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="height: 1200px; box-shadow: 0 0 1px 300px #FFC1B4; width: 1px; margin-top: -1070px; margin-left: 1010px;"><img style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" mce_style="transform: scale(0.1); pointer-events: none; z-index: 9; margin-left: -180px;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="width: 100%; pointer-events: none; margin-top: -1150px; opacity: 50%;"><img style="margin-left: -400px; transform: scale(1.8);" mce_style="margin-left: -400px; transform: scale(1.8);" src="https://static.vecteezy.com/system/resources/previews/015/723/303/non_2x/window-shadow-overlay-effect-free-png.png" mce_src="https://static.vecteezy.com/system/resources/previews/015/723/303/non_2x/window-shadow-overlay-effect-free-png.png" alt="fenetre et feuilles" /></div> <div style="height: 1700px; background-color: #ffd9d9; opacity: 30%; width: 1600px; margin-top: -1332px; margin-left: -550px; pointer-events: none;"><img style="transform: scale(0.1); pointer-events: none;" mce_style="transform: scale(0.1); pointer-events: none;" src="src" mce_src="src" alt="couleurunie" /></div> <div style="width: 100%; pointer-events: none; margin-top: -1555px; opacity: 50%;"><img style="transform: scale(1.6); margin-left: 650px;" mce_style="transform: scale(1.6); margin-left: 650px;" src="https://i.pinimg.com/originals/f1/c4/87/f1c48787da53b0ec1d81d5f1833d95b1.gif" mce_src="https://i.pinimg.com/originals/f1/c4/87/f1c48787da53b0ec1d81d5f1833d95b1.gif" alt="pixel perles rose" /></div> </div>