Site doesn't work on git push, but does on netlify deploy

Netlify Site Name: alexstephen.me

Build problem: I can run netlify deploy --prod on my local machine to have the site deploy. When I do a git push, the build fails with the following issue:

3:59:38 PM: Build ready to start
3:59:40 PM: build-image version: d2c6dbeac570350a387d832f64bc980dc964ad65 (focal)
3:59:40 PM: build-image tag: v4.8.0
3:59:40 PM: buildbot version: 785511f5c344fb31afdecdfe3e45beb4c5bb14ae
3:59:40 PM: Fetching cached dependencies
3:59:41 PM: Finished downloading cache in 1.336030724s
3:59:41 PM: Starting to extract cache
3:59:49 PM: Finished extracting cache in 7.127263551s
3:59:49 PM: Finished fetching cache in 8.501716512s
3:59:49 PM: Starting to prepare the repo for build
3:59:49 PM: Preparing Git Reference refs/heads/master
3:59:49 PM: Parsing package.json dependencies
3:59:50 PM: Different build command detected, going to use the one specified in the Netlify configuration file: 'hugo --gc --minify' versus 'hugo build' in the Netlify UI
3:59:50 PM: Starting build script
3:59:50 PM: Installing dependencies
3:59:50 PM: Python version set to 2.7
3:59:50 PM: Started restoring cached node version
3:59:52 PM: Finished restoring cached node version
3:59:52 PM: v12.18.0 is already installed.
3:59:52 PM: Now using node v12.18.0 (npm v6.14.4)
3:59:52 PM: Started restoring cached build plugins
3:59:52 PM: Finished restoring cached build plugins
3:59:53 PM: Attempting ruby version 2.7.1, read from environment
3:59:53 PM: Started restoring cached ruby version
3:59:53 PM: Finished restoring cached ruby version
3:59:55 PM: Using ruby version 2.7.1
3:59:55 PM: Using PHP version 8.0
3:59:55 PM: WARNING: The environment variable 'NODE_ENV' is set to 'production'. Any 'devDependencies' in package.json will not be installed
3:59:55 PM: Started restoring cached yarn cache
3:59:56 PM: Finished restoring cached yarn cache
3:59:56 PM: No yarn workspaces detected
3:59:56 PM: Started restoring cached node modules
3:59:56 PM: Finished restoring cached node modules
3:59:56 PM: Installing NPM modules using Yarn version 1.22.4
3:59:57 PM: yarn install v1.22.4
3:59:57 PM: [1/4] Resolving packages...
3:59:57 PM: [2/4] Fetching packages...
3:59:58 PM: info fsevents@2.3.2: The platform "linux" is incompatible with this module.
3:59:58 PM: info "fsevents@2.3.2" is an optional dependency and failed compatibility check. Excluding it from installation.
3:59:58 PM: [3/4] Linking dependencies...
3:59:58 PM: warning " > bootstrap@4.6.1" has unmet peer dependency "jquery@1.9.1 - 3".
3:59:58 PM: warning " > bootstrap@4.6.1" has unmet peer dependency "popper.js@^1.16.1".
3:59:59 PM: [4/4] Building fresh packages...
3:59:59 PM: Done in 2.66s.
3:59:59 PM: NPM modules installed using Yarn
4:00:00 PM: Installing Hugo 0.100.2
4:00:01 PM: hugo v0.100.2-d25cb2943fd94ecf781412aeff9682d5dc62e284+extended linux/amd64 BuildDate=2022-06-08T10:25:57Z VendorInfo=gohugoio
4:00:01 PM: Started restoring cached go cache
4:00:02 PM: Finished restoring cached go cache
4:00:02 PM: Installing Go version 1.14.4
4:00:02 PM: unset GOOS;
4:00:02 PM: unset GOARCH;
4:00:02 PM: export GOROOT='/opt/buildhome/.gimme_cache/versions/go1.14.4.linux.amd64';
4:00:02 PM: export PATH="/opt/buildhome/.gimme_cache/versions/go1.14.4.linux.amd64/bin:${PATH}";
4:00:02 PM: go version >&2;
4:00:02 PM: export GIMME_ENV='/opt/buildhome/.gimme_cache/env/go1.14.4.linux.amd64.env';
4:00:02 PM: go version go1.14.4 linux/amd64
4:00:02 PM: Installing missing commands
4:00:02 PM: Verify run directory
4:00:03 PM: ​
4:00:03 PM: ────────────────────────────────────────────────────────────────
4:00:03 PM:   Netlify Build                                                 
4:00:03 PM: ────────────────────────────────────────────────────────────────
4:00:03 PM: ​
4:00:03 PM: ❯ Version
4:00:03 PM:   @netlify/build 27.1.5
4:00:03 PM: ​
4:00:03 PM: ❯ Flags
4:00:03 PM:   baseRelDir: true
4:00:03 PM:   buildId: 62aa645a481fd30009ba6df2
4:00:03 PM:   deployId: 62aa645a481fd30009ba6df4
4:00:03 PM: ​
4:00:03 PM: ❯ Current directory
4:00:03 PM:   /opt/build/repo
4:00:03 PM: ​
4:00:03 PM: ❯ Config file
4:00:03 PM:   /opt/build/repo/netlify.toml
4:00:03 PM: ​
4:00:03 PM: ❯ Context
4:00:03 PM:   production
4:00:03 PM: ​
4:00:03 PM: ────────────────────────────────────────────────────────────────
4:00:03 PM:   1. build.command from netlify.toml                            
4:00:03 PM: ────────────────────────────────────────────────────────────────
4:00:03 PM: ​
4:00:03 PM: $ hugo --gc --minify
4:00:03 PM: Start building sites …
4:00:03 PM: hugo v0.100.2-d25cb2943fd94ecf781412aeff9682d5dc62e284+extended linux/amd64 BuildDate=2022-06-08T10:25:57Z VendorInfo=gohugoio
4:00:03 PM: WARN 2022/06/15 23:00:03 found no layout file for "HTML" for kind "taxonomy": You should create a template file which matches Hugo Layouts Lookup Rules for this combination.
4:00:03 PM: WARN 2022/06/15 23:00:03 found no layout file for "HTML" for kind "taxonomy": You should create a template file which matches Hugo Layouts Lookup Rules for this combination.
4:00:04 PM: Error: Error building site: POSTCSS: failed to transform "css/main.css" (text/css): Error: ENOENT: no such file or directory, stat '/opt/build/repo/stdin'
4:00:04 PM:     at Object.statSync (fs.js:1009:3)
4:00:04 PM:     at trackModified (/opt/build/repo/node_modules/tailwindcss/lib/lib/setupContextUtils.js:527:46)
4:00:04 PM:     at Object.getContext (/opt/build/repo/node_modules/tailwindcss/lib/lib/setupContextUtils.js:911:5)
4:00:04 PM:     at /opt/build/repo/node_modules/tailwindcss/lib/lib/setupTrackingContext.js:40:53
4:00:04 PM:     at /opt/build/repo/node_modules/tailwindcss/lib/processTailwindFeatures.js:38:11
4:00:04 PM:     at plugins (/opt/build/repo/node_modules/tailwindcss/lib/index.js:30:63)
4:00:04 PM:     at LazyResult.runOnRoot (/opt/build/repo/node_modules/postcss/lib/lazy-result.js:339:16)
4:00:04 PM:     at LazyResult.runAsync (/opt/build/repo/node_modules/postcss/lib/lazy-result.js:393:26)
4:00:04 PM:     at LazyResult.async (/opt/build/repo/node_modules/postcss/lib/lazy-result.js:221:30)
4:00:04 PM:     at LazyResult.then (/opt/build/repo/node_modules/postcss/lib/lazy-result.js:206:17) {
4:00:04 PM:   errno: -2,
4:00:04 PM:   syscall: 'stat',
4:00:04 PM:   code: 'ENOENT',
4:00:04 PM:   path: '/opt/build/repo/stdin'
4:00:04 PM: }
4:00:04 PM: Total in 1138 ms
4:00:04 PM: ​
4:00:04 PM: ────────────────────────────────────────────────────────────────
4:00:04 PM:   "build.command" failed                                        
4:00:04 PM: ────────────────────────────────────────────────────────────────
4:00:04 PM: ​
4:00:04 PM:   Error message
4:00:04 PM:   Command failed with exit code 255: hugo --gc --minify (https://ntl.fyi/exit-code-255)
4:00:04 PM: ​
4:00:04 PM:   Error location
4:00:04 PM:   In build.command from netlify.toml:
4:00:04 PM:   hugo --gc --minify
4:00:04 PM: ​
4:00:04 PM:   Resolved config
4:00:04 PM:   build:
4:00:04 PM:     command: hugo --gc --minify
4:00:04 PM:     commandOrigin: config
4:00:04 PM:     environment:
4:00:04 PM:       - HUGO_VERSION
4:00:04 PM:       - HUGO_ENV
4:00:04 PM:       - NODE_ENV
4:00:04 PM:       - HUGO_ENABLEGITINFO
4:00:04 PM:     publish: /opt/build/repo/public
4:00:04 PM:     publishOrigin: config
4:00:04 PM:   redirects:
4:00:05 PM:     - from: /npmjs/*
      status: 200
      to: /npmjs/
  redirectsOrigin: config
Caching artifacts
4:00:05 PM: Started saving node modules
4:00:05 PM: Finished saving node modules
4:00:05 PM: Started saving build plugins
4:00:05 PM: Finished saving build plugins
4:00:05 PM: Started saving yarn cache
4:00:05 PM: Finished saving yarn cache
4:00:05 PM: Started saving pip cache
4:00:05 PM: Finished saving pip cache
4:00:06 PM: Creating deploy upload records
4:00:05 PM: Started saving emacs cask dependencies
4:00:05 PM: Finished saving emacs cask dependencies
4:00:05 PM: Started saving maven dependencies
4:00:05 PM: Finished saving maven dependencies
4:00:05 PM: Started saving boot dependencies
4:00:05 PM: Finished saving boot dependencies
4:00:07 PM: Failed during stage 'building site': Build script returned non-zero exit code: 2 (https://ntl.fyi/exit-code-2)
4:00:05 PM: Started saving rust rustup cache
4:00:05 PM: Finished saving rust rustup cache
4:00:05 PM: Started saving go dependencies
4:00:06 PM: Finished saving go dependencies
4:00:06 PM: Build failed due to a user error: Build script returned non-zero exit code: 2
4:00:07 PM: Failing build: Failed to build site
4:00:07 PM: Finished processing build request in 26.945282649s

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