The button carries a full matrix: seven variants, three sizes, five states, and four content configurations — every cell defined, none left to improvisation. The variants aren't decorative; each maps to a distinct action classification, so the interface communicates intent through form. A primary action looks primary; a destructive one is unmistakable; a soft, reversible negative reads differently from an irreversible one. That's the systematic principle doing real UX work: the visual language of the button tells the user what kind of decision they're about to make.

The most consequential decision here was architectural — solid variants composite a translucent overlay on hover rather than swapping to a hardcoded hover color. It means a button's background can change for any reason (a rebrand, a context, a state) and the hover keeps working untouched. That's modularity at the component level: the hover behavior doesn't depend on knowing the color.

Inputs, selectors, checkboxes, radios, and switches look different but behave identically: a quiet border at rest, a clear strengthening on hover, a purple focus ring that's reserved exclusively for focus across the entire system, and a distinct error treatment that mirrors the focus geometry. Learn one field and you understand all of them — the systematic payoff.

The disabled state shows the level of care that separates a real system from a styled mockup. The whole control doesn't dim — only the interactive content drops to a low opacity, while the label and helper text stay fully legible, because the user still needs to read why a field is unavailable. A blunt system greys out everything; a considered one dims only what stopped being interactive.

The table is where a design system either proves itself or falls apart, because it stacks the most states: row hover, selection, selection-while-hovering, expandable sub-rows, sortable headers, inline controls, and status badges. None of it required a single bespoke value. The entire visual hierarchy is expressed through the shared surface and overlay model — hover and selection are overlays, sub-rows recess onto the sunken surface. The table didn't need its own design language; it spoke the system's.

Most components map cleanly onto the global tokens. The segmented control didn't — its track-and-pill contrast needed values the shared overlays couldn't express. Rather than forcing it or littering the component with one-off hacks, it got its own small, named sub-token set. Knowing when not to reuse a token is as systematic as reusing one: the exception is contained, documented, and obvious, instead of leaking ambiguity into the rest of the system.

The structural components encode hierarchy through three surface levels: the app canvas sits sunken, panels sit on the base surface, and overlays like modals and dropdowns rise above on the raised surface. Depth isn't decoration — it's information about what sits on top of what. The 52px title bar is sized to anchor the top of a panel and hold its ghost icon buttons with even breathing room, and the radius scale reinforces the same nesting: tight radii on the things you click, generous radii on the containers that hold them, the largest on the outermost shell.

color-mix() can compute hover states from base colors elegantly — and it was rejected. Browser support isn't complete across targets, output varies slightly between implementations, and most critically, the computation happens in the browser's style engine where it isn't trivially inspectable. When a hover state looks wrong, the developer needs the computed value. The pseudo-element overlay approach is more verbose but completely debuggable: every value is a token reference, every token has a computed hex, nothing is hidden.

Component-scoped tokens create parallel scales — --button-padding-md, --input-padding-md, all the same value, all needing updates together. Global tokens eliminate that: the component derives its size from the global scale, and if the scale changes, every component changes. (Layer 2 component tokens are the exception — they're semantic aliases, not size definitions.)

The contrast scale was renamed from light/medium/dark to a perceptual-weight vocabulary. Directional names lie under inversion: --text-dark is white in dark mode and black in light mode — the name contradicts the outcome. A name describing perceptual weight is stable in both modes. It also stopped the contrast scale from sharing vocabulary with the elevation scale, eliminating the ambiguity between, say, surface-dark and text-dark.

Search is the fastest path to a known record. It lives at the far left of the toolbar, the natural starting point for the eye, and it searches across all visible and hidden columns — not just what's rendered on screen. A user looking for "Acme Corp" shouldn't have to know which column the name lives in.

Any column should be filterable, not just status. The filter type adapts to the data type of the column: categorical fields (vendor, category, account) offer multi-select lists; numeric fields (amount, tax) offer range and comparison operators (greater than, less than, between); date fields offer date-range pickers and relative presets (this month, last quarter); text fields offer contains / equals / starts-with matching. Multiple filters can be active at once and combine with AND logic, with the active set shown as removable chips so the user always knows what scope they're looking at.

On top of this general filtering, the most common filters get promoted to always-visible quick chips. In an accounting context, status (Paid, Pending, Overdue, Draft, Partial) is the single most-used filter, so it earns a permanent spot in the toolbar as one-tap chips — a convenience shortcut layered on top of the full filtering system, not a replacement for it. Color reinforces these chips: the same color used in the status tags inside the cells appears in the chip when active, creating visual continuity between the control and the data it surfaces.

Every column header is a sort trigger. The sort state is always visible — a directional indicator sits in the active header so the user can always see what the table is ordered by. Clicking a second time reverses direction. Clicking a new column clears the previous sort.

Pinned rows (see below) always stay at the top regardless of sort order. Sort applies to the unpinned data only.

Not every user needs every column. A bookkeeper reviewing transactions cares about vendor, amount, and status. An accountant reconciling a period cares about account, tax, and date. Column visibility lets each user shape the table to their workflow without losing access to any data.

The column picker is a popover — not a modal, not a separate settings page. It's accessed from a "Columns" button in the toolbar and dismissed by clicking elsewhere. The table reflows immediately as columns are toggled on and off.

Drag-to-reorder lets users place the columns they reference most frequently at the leftmost visible position, reducing eye travel. This matters especially on wide tables where the most important column might otherwise be two or three scrolls away. The interaction is drag-and-drop on column headers, with a drop indicator showing the target position.

Default column widths are a designer's best guess — but the right width depends entirely on the data a given user is working with. Someone reviewing detailed memos needs a wide description column; someone scanning amounts wants it narrow and out of the way. Column resizing hands that decision to the user.

The interaction is a drag handle on the right edge of each column header. Hovering the boundary changes the cursor to a horizontal resize indicator; dragging widens or narrows the column in real time while the rest of the table reflows around it. A double-click on the handle auto-fits the column to its widest visible value — the fastest way to reveal fully truncated content without manual dragging.

When a table is wide enough to require horizontal scrolling, context collapses fast. A user scrolling right loses sight of which row they're looking at. Pinning a column to the left — typically the record identifier, like Invoice ID or Vendor — keeps it anchored while the rest of the columns scroll freely beneath it.

Right-pinning is equally important for action columns: bulk checkboxes, inline edit triggers, or row-level action menus can be pinned to the right so they remain accessible regardless of scroll position.

Some rows are structurally important regardless of how the table is sorted or filtered. Totals rows, summary rows, or high-priority records that need to stay in view — these can be pinned to the top or bottom of the table. A pinned row receives a distinct visual treatment (a subtle background tint) to distinguish it from sortable data rows.

Grouping reorganizes the table by a categorical field — category, account, vendor, status — without changing the underlying data. Each group has a header row with the group name and optionally a subtotal. This is particularly useful for reviewing a period's transactions by category, or comparing spending across accounts.

Grouping is additive to sorting and filtering. A user can filter to "Paid", sort by amount, and group by category simultaneously.

Wide tables should scroll horizontally — they should never wrap columns or collapse to an accordion. Collapsing breaks the tabular structure that makes data comparable. Horizontal scroll preserves it. The scroll container clips at the table boundary, and a faint shadow edge appears on the right when there is more content to reveal.

Not every edit justifies opening a detail panel. Fields like memo, notes, tags, or category can be edited directly inside the table cell — click to activate, type, tab to commit. Inline editing reduces round-trips and keeps the user's mental context on the table, not a sidebar.

Editability is communicated subtly: a hover state reveals the cell's editable affordance (a faint border or pencil icon) without permanently adding visual noise to every row.

The format of a cell is a design decision, not a default. In Puzzle's table system, every data type has a correct display format:

• Numbers — right-aligned, tabular numerals, fixed decimal places. Right-alignment lets digits line up by place value, making comparison across rows instant.
• Amounts — color-coded. Positive values in green, negative in red. The sign and the color are redundant signals, which is intentional: color should never be the only carrier of meaning.
• Statuses — displayed as chips, never as plain text. A chip with a background color gives status instant scannability. Each status has a fixed color that is semantically meaningful and used nowhere else in that color (Overdue is always red, Paid is always green).
• Long text — truncated at the column boundary, with the full value available on hover. Covered in detail below.
• People / entities — represented with an avatar or initials circle alongside the name wherever identity recognition is faster than reading a name string.

Free-text fields are the enemy of a tidy table. A memo, a transaction description, or a note can run to a sentence or more — and if a single long value is allowed to dictate column width, it steals space from every other column and forces unnecessary horizontal scrolling. The solution is to truncate at the column boundary with a trailing ellipsis, so each cell shows as much as fits and no more.

Truncation only works if the hidden text stays recoverable. Hovering a truncated cell reveals the full value in a tooltip — the complete description appears in an overlay anchored to the cell, without disturbing the surrounding rows. This is the quick-peek path: the user reads the full text, moves the cursor away, and the table snaps back to its compact form. Nothing is lost; it's simply held back until asked for.

Crucially, the tooltip only appears when text is actually clipped. A cell whose content fits fully shows no tooltip, because there's nothing more to reveal — a tooltip on already-complete text is noise. This keeps the affordance honest: a tooltip always means "there's more here."

Row striping (alternating background tones on odd and even rows) is a usability aid for dense tables where the eye struggles to track horizontally across a row. It's togglable — some users find it visually noisy, others find it essential. It's off by default and user-controlled.

When a user selects multiple rows, a contextual action bar appears above the table. This bar contains only the actions that apply to the selection: approve, categorize, export, delete. The bar is prominent enough to be noticed but disappears entirely when nothing is selected — it only exists when it's needed.

The row count is always shown in the bar so the user knows the scope of the action they're about to take. Destructive actions (delete) are visually distinguished from reversible ones.

Reducing an invoice or bill balance by applying a payment against it. This is the act most users think of as "the work" — but it's only one of three ideas the system has to keep straight.

Connecting money movements across accounts and sources — for example, a processor payout flowing into a bank account — and representing money that's "in transit" via clearing accounts. Linking is about where the money is; matching is about what the money pays for. They look similar and are easy to confuse, which is precisely why double counting happens when both are recorded for the same real-world movement.

A payment represents cash movement that can exist with or without a linked bank transaction. A check received today but not yet deposited is a real payment. So is money applied to a customer before any invoice exists. Treating the payment as its own durable record — not a side effect of a bank transaction or an invoice — is what allows every other state to exist cleanly.

The exact-match case: a payment lands and clears a single open invoice in full. This is the happy path, and it should feel instant — one confirmation, balances recompute, the invoice flips to paid. Getting this case to feel effortless is what earns the user's trust to attempt the harder ones.

One payment frequently covers several invoices at once. The allocation UI supports multi-selecting invoices and shows the amount applied to each, with a running residual so the user always knows how much of the payment is still unallocated. Balances for every affected invoice recompute deterministically.

A payment that only covers part of an invoice leaves that invoice open with an explicit remaining balance. The allocation amount is editable, so the user can split a payment exactly as the real money was intended. The invoice's partial state is visible everywhere it appears.

When the payment amount doesn't equal the invoice amount, the system handles it explicitly rather than silently. An underpayment can leave the invoice open with a remaining balance, or — in future phases — close it against a designated adjustment bucket for discounts or write-offs. An overpayment creates a customer credit or an unallocated remainder that can be applied later. The mismatch is surfaced, never swept away.

The action that anchors the whole system. Unapply reverts the allocations and reverses their accounting impact, while keeping the payment record itself fully intact. The user isn't deleting anything — they're detaching a payment from the invoices it was matched to, so it returns to an unallocated state, ready to be matched correctly.

From any state, a user can change allocations or move a payment from one set of invoices to another — correcting a mistake without ever touching the underlying payment. This is the everyday recovery path: matched the wrong invoice, fix it in seconds, balances follow.

Two payment records sometimes represent the same real-world money movement — one created from a bank transaction, another from an invoice. The system has to make these findable and resolvable, so users can collapse the duplicate without losing the matching work already done. Left unaddressed, duplicates are a leading source of reconciliation exceptions.

When a payment doesn't exactly match the invoice amount, users can write out the difference directly from the matching interface, keeping the ledger clean without leaving the workflow.

A payment can be applied to a customer on the receivable side even when the exact invoice isn't known yet. The system holds the unallocated amount and lets the user resolve it later, without blocking the workflow or leaving the ledger in a broken state.

The two-panel UI shows bank transactions on one side and invoices or bills on the other. Panels can be resized to give more room to whichever side needs focus. Orientation toggles between horizontal and vertical to match the user's screen and working style. Panels can also be flipped so transactions or invoices lead, depending on how the user naturally approaches the task.

When a user starts from a bank transaction or invoice that belongs to a specific customer, the opposite panel automatically filters to that customer's records. This dramatically reduces the search space and prevents mismatches, without any manual filter setup.

As a user selects items on one side, the system will proactively protect and suggest matching selections on the other side, reducing conflicts and surfacing the most likely matches. This is the next layer of intelligence on top of the current contextual filtering.