"""Six scientific illustrations for the home frontier cards, as inline SVG data URIs. The old backgrounds were CSS gradient recipes — blue field, cyan lines, a glow — which is why every card read as decoration. Each card now carries an actual diagram of its subject, drawn in the site's palette and nothing else: 1 metasurface unit-cell array: split-rings, crosses, patches — one cell picked out in gold 2 photonic-crystal hole lattice with a line-defect waveguide and a gold cavity site 3 bowtie nanoantenna: two gold tips, the hotspot in the gap, thin field lines around it 4 integrated photonic circuit: a Mach–Zehnder with couplers, a gold ring resonator, photons 5 anticrossing: dashed bare photon and exciton lines, solid polariton branches, Rabi gap 6 auxetic re-entrant honeycomb — an architected mechanical lattice Vector, ~2 KB apiece, embedded in meta27.css: no new HTTP requests, no stock imagery, no AI texture. A dark vignette sits over each drawing where the caption lives, so the type stays as readable as before. """ import re from urllib.parse import quote NAVY = '#0d2a3d' CYAN = '#39c4de' CYAN_S = '#7fdcee' GOLD = '#d8b46a' GOLD_S = '#e7cf9e' def svg(body, w=600, h=400): doc = ('' '%s' % (w, h, w, h, NAVY, body)) return 'url("data:image/svg+xml,%s")' % quote(doc, safe="~()*!.'/:,%=<>-") # ---------------------------------------------------------------- 1 · metasurface array def metasurface(): """A periodic surface, not an alphabet: three unit-cell families (split-ring, cross, patch) repeated as a regular super-cell, secondary strokes at one opacity, one gold SRR framed.""" cells = [] kinds = ['ring', 'cross', 'patch'] for r in range(4): for c in range(6): x, y = 55 + c * 100, 52 + r * 100 kind = kinds[c % 3] hot = (r == 1 and c == 3) col = GOLD if hot else CYAN_S op = '0.92' if hot else '0.35' if kind == 'ring': cells.append('' % (x, y, col, op, (r * 90 - 104) % 360, x, y)) elif kind == 'cross': cells.append('' % (x - 17, y, x, y - 17, col, op)) else: cells.append('' % (x - 14, y - 14, col, op)) if hot: cells.append('' % (x - 35, y - 35, GOLD)) return svg(''.join(cells)) # ---------------------------------------------------------------- 2 · photonic crystal def photonic_crystal(): holes = [] for r in range(7): y = 40 + r * 54 off = 27 if r % 2 else 0 for c in range(12): x = 30 + c * 52 + off if r == 3: # line defect: the waveguide row continue if r == 2 and c == 6: # cavity: one missing hole, glowing holes.append('' % (x, y, GOLD)) holes.append('' % (x, y, GOLD_S)) continue holes.append('' % (x, y, CYAN_S)) # guided mode in the defect row — a hint, not a decoration: faint cyan, the cavity keeps # the card's one gold accent holes.append('' % CYAN_S) return svg(''.join(holes)) # ---------------------------------------------------------------- 3 · plasmonic bowtie def plasmonics(): parts = [] # field lines: nested ellipses through the gap for i, (rx, ry, o) in enumerate([(70, 40, .38), (115, 72, .28), (165, 108, .18), (215, 146, .10)]): parts.append('' % (rx, ry, CYAN, o)) # bowtie: two gold triangles tip to tip, small gap parts.append('' % GOLD) parts.append('' % GOLD) # hotspot in the gap parts.append('' % CYAN_S) parts.append('' % CYAN_S) parts.append('') return svg(''.join(parts)) # ---------------------------------------------------------------- 4 · quantum photonic circuit def quantum(): p = [] wg = 'fill="none" stroke="%s" stroke-opacity="0.75" stroke-width="4"' % CYAN_S # two waveguides forming an MZI: couplers at x 140-200 and 400-460 p.append('' % wg) p.append('' % wg) # phase shifter pad on upper arm — circuit element, cyan like the guides p.append('' % CYAN_S) # ring resonator tangent to the lower bus with a visible coupling gap: the card's gold element p.append('' % GOLD) # single photons on the inputs/outputs, white so the ring keeps the only gold for x, y in [(48, 150), (92, 150), (540, 178), (566, 250)]: p.append('' % (x, y)) # faint second circuit layer for depth p.append('' % CYAN) p.append('' % CYAN) return svg(''.join(p)) # ---------------------------------------------------------------- 5 · anticrossing def light_matter(): p = [] # bare modes, dashed: photon (diagonal) and exciton (horizontal) p.append('' % CYAN_S) p.append('' % CYAN_S) # polariton branches, solid gold, avoiding the crossing p.append('' % GOLD) p.append('' % GOLD_S) # Rabi splitting marker at the anticrossing p.append('') p.append('') return svg(''.join(p)) # ---------------------------------------------------------------- 6 · auxetic lattice def multiphysics(): cell = ('M0 0 L46 18 L92 0 M0 0 L0 62 M92 0 L92 62 M0 62 L46 44 L92 62') p = [] for r in range(5): for c in range(6): x, y = 18 + c * 96, 12 + r * 84 hot = (r == 2 and c == 3) col, op, w = (GOLD, '0.9', '5') if hot else (CYAN_S, '0.3', '4') p.append('' % (cell, x, y, col, op, w)) return svg(''.join(p)) VIGNETTE = 'linear-gradient(180deg, rgba(6,18,28,.18) 0%, rgba(6,18,28,0) 32%, rgba(6,18,28,.08) 58%, rgba(6,18,28,.72) 100%)' BGS = { 1: metasurface(), 2: photonic_crystal(), 3: plasmonics(), 4: quantum(), 5: light_matter(), 6: multiphysics(), } css = open('meta27.css', encoding='utf-8').read() for n, bg in BGS.items(): pat = re.compile(r'\.bg-%d\{[^}]*\}' % n) rule = '.bg-%d{background:%s, %s center/cover no-repeat, %s}' % (n, VIGNETTE, bg, NAVY) css, k = pat.subn(lambda m: rule, css, count=1) assert k, n print('bg-%d : %d octets de SVG' % (n, len(bg))) open('meta27.css', 'w', encoding='utf-8').write(css) print('meta27.css : %d octets' % len(css))