{"schema":"record/v1","id":"art_01M5NNSW5TJYP4CZJKY0WV7QZE","type":"article","revision":1,"etag":"\"r1.s0\"","title":"How do I convert a pixel-based column grid into a fluid grid, and what checks catch errors?","summary":"Marcotte (A List Apart, 2009-03-03) gives one formula, target / context = result, applied to a 988 px grid of seven 124 px columns and 20 px gutters: 700/988 = 70.85%, 144/988 = 14.575%, and after the container changes the divisor changes too (700/844 = 82.938%). It also caps width with max-width in ems and warns that browsers round sub-pixel widths. Carbon and GOV.UK document the same idea in current systems: Carbon column widths between breakpoints are a percentage of the grid area, GOV.UK widths are percentages from quarters to full. The article is 2009 practice and predates CSS Grid and media-query-driven systems.","status":"active","body":{"text":"Marcotte (A List Apart, 2009-03-03) gives one formula, target / context = result, applied to a 988 px grid of seven 124 px columns and 20 px gutters: 700/988 = 70.85%, 144/988 = 14.575%, and after the container changes the divisor changes too (700/844 = 82.938%). It also caps width with max-width in ems and warns that browsers round sub-pixel widths. Carbon and GOV.UK document the same idea in current systems: Carbon column widths between breakpoints are a percentage of the grid area, GOV.UK widths are percentages from quarters to full. The article is 2009 practice and predates CSS Grid and media-query-driven systems.\n\nCurator qualifications: Curator recomputed 700/988 = 70.8502%, 144/988 = 14.5749%, 700/844 = 82.9384%, matching Marcotte's 70.85%, 14.575% and 82.938%.\n\nEvidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.","citations":[{"url":"https://alistapart.com/article/fluidgrids/","note":"candidate evidence excerpts"},{"url":"https://github.com/alphagov/govuk-frontend/tree/6c365ebaa998bc2a4ea20fe89c583907e38245dd/packages/govuk-frontend/src/govuk","note":"candidate evidence excerpts"}]},"categories":["T17"],"tags":[],"language":"en","visibility":"public","moderation":{"state":"visible","reason":null},"evidence":{"inspection":"source_inspected","execution":"not_run","review":"unreviewed","review_revision":null,"claims":[{"url":"https://alistapart.com/article/fluidgrids/","claim":"Marcotte (A List Apart, 2009-03-03) gives one formula, target / context = result, applied to a 988 px grid of seven 124 px columns and 20 px gutters: 700/988 = 70.85%, 144/988 = 14.575%, and after the container changes the divisor changes too (700/844 = 82.938%). It also caps width with max-width in ems and warns that browsers round sub-pixel widths. Carbon and GOV.UK document the same idea in current systems: Carbon column widths between breakpoints are a percentage of the grid area, GOV.UK widths are percentages from quarters to full. 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It also caps width with max-width in ems and warns that browsers round sub-pixel widths. Carbon and GOV.UK document the same idea in current systems: Carbon column widths between breakpoints are a percentage of the grid area, GOV.UK widths are percentages from quarters to full. The article is 2009 practice and predates CSS Grid and media-query-driven systems.\n\nCurator qualifications: Curator recomputed 700/988 = 70.8502%, 144/988 = 14.5749%, 700/844 = 82.9384%, matching Marcotte's 70.85%, 14.575% and 82.938%.\n\nEvidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.","citations":[{"url":"https://alistapart.com/article/fluidgrids/","note":"candidate evidence excerpts"},{"url":"https://github.com/alphagov/govuk-frontend/tree/6c365ebaa998bc2a4ea20fe89c583907e38245dd/packages/govuk-frontend/src/govuk","note":"candidate evidence excerpts"}]},"tags":[],"type":"article","links":[],"title":"How do I convert a pixel-based column grid into a fluid grid, and what checks catch errors?","rights":[{"notes":"Applies to this original summary only, not to the cited sources.","hosting":"permitted","component":"documentation","license_id":null,"modification":"unknown","evidence_urls":[],"model_training":"unknown","redistribution":"permitted"}],"summary":"Marcotte (A List Apart, 2009-03-03) gives one formula, target / context = result, applied to a 988 px grid of seven 124 px columns and 20 px gutters: 700/988 = 70.85%, 144/988 = 14.575%, and after the container changes the divisor changes too (700/844 = 82.938%). It also caps width with max-width in ems and warns that browsers round sub-pixel widths. Carbon and GOV.UK document the same idea in current systems: Carbon column widths between breakpoints are a percentage of the grid area, GOV.UK widths are percentages from quarters to full. The article is 2009 practice and predates CSS Grid and media-query-driven systems.","evidence":{"claims":[{"url":"https://alistapart.com/article/fluidgrids/","claim":"Marcotte (A List Apart, 2009-03-03) gives one formula, target / context = result, applied to a 988 px grid of seven 124 px columns and 20 px gutters: 700/988 = 70.85%, 144/988 = 14.575%, and after the container changes the divisor changes too (700/844 = 82.938%). It also caps width with max-width in ems and warns that browsers round sub-pixel widths. Carbon and GOV.UK document the same idea in current systems: Carbon column widths between breakpoints are a percentage of the grid area, GOV.UK widths are percentages from quarters to full. 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