frames/.agents/skills/changelog-video/references/build-spec.md

Build Spec — square 1080 changelog master

Single-doc index.html: scenes are absolutely-positioned .slide clips on track 1; the master timeline tl (MUST be named tl — seam-stamp emits tl.*) is paused, padded to total duration, registered as window.__timelines["main"]. See examples/master-skeleton.html for the verbatim scaffold.

Brand tokens

@font-face {
  font-family: "Inter";
  font-weight: 400;
  src: url(assets/fonts/Inter-400.woff2) format("woff2");
}
@font-face {
  font-family: "Inter";
  font-weight: 500;
  src: url(assets/fonts/Inter-500.woff2) format("woff2");
}
@font-face {
  font-family: "Inter";
  font-weight: 700;
  src: url(assets/fonts/Inter-700.woff2) format("woff2");
}
@font-face {
  font-family: "Inter";
  font-weight: 800;
  src: url(assets/fonts/Inter-800.woff2) format("woff2");
}
@font-face {
  font-family: "JetBrains Mono";
  font-weight: 400;
  src: url(assets/fonts/JetBrainsMono-400.woff2) format("woff2");
}
/* ink #f5f6f4 · ink2 rgba(245,246,244,.72) · dim rgba(245,246,244,.66) —
   NOT .45: the contrast gate fails small text under 4.5:1 over the glass.
   green #5ef17c (RATIONED: one moment per scene) · bg #0a0c0b ·
   chip-bg rgba(10,12,11,.78) · glass-line rgba(190,255,205,.32) */

Copy fonts from <SKILL_DIR>/assets/fonts/ into the project's assets/fonts/ (local @font-face with format('woff2') embeds at render). Glass card: chip-bg fill, 1px glass-line border, radius 22, box-shadow: 0 24px 60px rgba(0,0,0,.5). NO backdrop-filter. Chips: mono 18-22px, radius 12, 1px rgba(255,255,255,.14) border on rgba(255,255,255,.05). Display type: Inter 800. Body: Inter. Everything code/UI-label: JetBrains Mono. Safe margins x/y ∈ [76, 1004].

Animated background (the house pattern)

Encode the bundled source to the film's exact duration — the render compiler shortens a video's slot to the media length, so the encode must be ≥ total:

ffmpeg -y -stream_loop 15 -i <SKILL_DIR>/assets/bg-pattern.mp4 -t <TOTAL> \
  -vf "scale=1080:1080,fps=30,eq=saturation=0.72,[email protected]:t=fill" \
  -an -c:v libx264 -crf 20 -pix_fmt yuv420p assets/bg-pattern-<TOTAL>s.mp4

Keep the darkening crush — the raw pattern is far too loud. Mount as <video id="bg-video" class="clip" muted> on track 0 + a static rgba(8,10,9,.25) scrim div. <video> needs the id (silent/black otherwise) and must stay flat 2D (no 3D ancestors).

Scene anatomy

• Chrome (untimed, z 6): kicker chip top-left FRAMES WEEKLY · <RANGE>, progress dots top-right (one per theme; tl.set backgroundColor at each cut — active #f5f6f4, done .45; never tl.call for state).
• Title (≤2s): mono kicker date, Inter 800 h1 ~104px, green rule sweep.
• Theme scene: sec-chip 0N · THEME NAME (top 128) + Inter 800 headline ~54px (top 186) + the mock (from the visualization registry) filling y ∈ [288, 944].
• Outro (≤3.5s): kicker FULL DIGEST, "See what shipped." ~96px, green rule, mono URL chip, tag line. Fade all + chrome ~0.5s before end.
• Caption rail per script-voice.md (top: 990, font-size: 32px, height: 52). Mandatory — populate the master-skeleton's LINES array from captions.json before render; see SKILL.md step 5.

Seams + internal life (doctrine mechanics)

• ledger.json: every ordinary seam cut-the-curve LEFT (x, dir −1), exit and entry selectors = the slide wrappers. Outro entry travel: 8.
• seam-stamp.mjs --ledger ledger.json --write index.html owns ALL wrapper entries/exits — author none yourself. Title (film open) authors its own entry only.
• Slides: CSS opacity: 0 base; data-start = exactly the cut time.
• Each scene's shell (chip, headline, mock chrome, initial state) is COMPOSED at local t=0 — the wrapper flies it in. Internal reveals start ≥0.4s after the cut and end ≥0.45s before the next cut (stamped exits begin at cut −0.34s).
• Every internal beat lands on a VO word from transcript.json. Name each scene's sustained-motion route in the plan (sequenced UI life for mocks, staged reveals for checklists). One green moment per scene.
• Init states via gsap.set(...) at build time; animation via sequential tl.to(...) only (no plain-object keyframes, no repeat:-1, no tweening left/top — set base position in CSS, tween x/y). Counters: object tween with an onUpdate in the tween config (cache DOM refs; never tl.eventCallback).

Lint/check gotchas (all hit before, all pre-solved)

• Mock containers with intentional stacking: data-layout-allow-overlap on the slide root; elements a playhead/line crosses: data-layout-allow-occlusion.
• Dim text: rgba(245,246,244,.66) minimum (contrast gate).
• Audio: every <audio> carries an id. BGM: the house track ships at <SKILL_DIR>/assets/bgm.mp3 (159s instrumental) — copy it to the project as bgm.mp3 and mount on its own track: <audio id="bgm" src="bgm.mp3" data-start="0" data-duration="<TOTAL>" data-track-index="2" data-volume="0.14" data-media-start="0"> (0.14 sits under the VO; use a user-supplied track only when given one).
• Preview server caches the bundle — RESTART after edits, then verify on the raw comp page (/api/projects/<id>/preview/comp/index.html) via window.__player.seek(t).