Here is a list of some beautiful CSS speech bubbles examples.
Pure CSS Chat Bubble Animations [WIP]
Dev: Alissa
A depressed CSS chat bubble
Dev: Jennifer Hedgcock
Pure CSS Chat Bubble shape
Dev: CodingDecoding
CSS Chat Bubble
Dev: Jamie Le Souef
Hello… I guess…
Dev: Alvaro Montoro
CSS Message Bubble
Dev: Daniel Kovacs
iMessage gradient effect
Dev: Lucas Bebber
Message Bubbles
Dev: Michael Rouse
Chat Bubbles
Dev: Alex Wright
Apple iMessage in CSS
Dev: Matt Smith
Pure CSS Thought Bubbles
Dev: Grant
Chatboard
Dev: florent
Chat panel
Dev: SBC
Chat Bubbles in CSS
Dev: Jason Founts
Direct Messaging
Dev: Momcilo Popov
iOS 13 Chat bubbles
Dev: Samuel Kraft
Pure CSS Speech Bubbles
Dev: Michael Chernin
Chat Bubbles
Dev: Dave Alger
Comic Book Speech Bubbles with SVG
Dev: Dudley Storey
Hello, World
Dev: kirsten allen
CSS speech bubbles
Dev: JP de la Torre
Comic Sans Criminal
Dev: Jesse Shawl
Flex chat bubbles | Responsive chat bubbles
Dev: Kristina
Chat Window Concept Bubbles
Dev: Ashwin Saxena
Speech bubbles
Dev: rajeshdn
Speech bubbles
Dev: Tanner
Speech bubbles
Dev: rajeshdn
CSS stacked chat bubbles (Messenger style)
Dev: J.M. CIery
Speech Bubbles
Dev: Daniel Mackay
Pure CSS speech and thought bubbles
Dev: Joe Hastings
Alternating speech bubbles
Dev: Kevin Østerkilde
Speech bubble
Dev: Ana Tudor
Comic Director Splash Animation
Dev: Adam Argyle
CSS Speech Bubble
Dev: Ga Satrya 🇮🇩
Speech Bubble Caret
Dev: GRAY GHOST