diff --git a/fhir-date-period-range-matching.svg b/fhir-date-period-range-matching.svg
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+<svg xmlns="http://www.w3.org/2000/svg" width="1100" height="810" viewBox="0 0 1100 810" font-family="Segoe UI, Arial, sans-serif">
+<rect width="1100" height="810" fill="#ffffff"/>
+<text x="550.0" y="30" font-size="22" font-weight="700" fill="#1a1a2e" text-anchor="middle">FHIR date: Matching gegen Period/Range (Containment vs. Overlap)</text>
+<text x="550.0" y="52" font-size="14" fill="#555" text-anchor="middle">Suchwert: date=&lt;praefix&gt;2023-06-15  |  Graue Balken = Beispiel-Period der Ressource</text>
+<text x="30" y="100" font-size="20" font-weight="700" fill="#111">gt</text>
+<text x="30" y="120" font-size="12.5" fill="#555">Overlap genuegt: Period muss nur ueber die Grenze hinausragen.</text>
+<rect x="671.0" y="128" width="369.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="220" y1="136" x2="1040" y2="136" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,136 1033,132 1033,140" fill="#333"/>
+<line x1="671.0" y1="116" x2="671.0" y2="156" stroke="#c62828" stroke-width="2.5" />
+<text x="671.0" y="110" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="260" y="157" width="321.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="420.5" y="198" font-size="11" fill="#444" text-anchor="middle">Period A: komplett davor</text>
+<line x1="411.5" y1="135" x2="429.5" y2="153" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="411.5" y1="153" x2="429.5" y2="135" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="581.0" y="157" width="160.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="661.0" y="198" font-size="11" fill="#444" text-anchor="middle">Period B: ueberlappt Grenze</text>
+<path d="M 652.0 144 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="741.0" y="157" width="259.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="870.5" y="198" font-size="11" fill="#444" text-anchor="middle">Period C: komplett danach</text>
+<path d="M 861.5 144 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<text x="30" y="270" font-size="20" font-weight="700" fill="#111">sa</text>
+<text x="30" y="290" font-size="12.5" fill="#555">Vollstaendige Trennung noetig: Period muss komplett hinter der Grenze liegen.</text>
+<rect x="671.0" y="298" width="369.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="220" y1="306" x2="1040" y2="306" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,306 1033,302 1033,310" fill="#333"/>
+<line x1="671.0" y1="286" x2="671.0" y2="326" stroke="#c62828" stroke-width="2.5" stroke-dasharray="4,4"/>
+<text x="671.0" y="280" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="260" y="327" width="321.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="420.5" y="368" font-size="11" fill="#444" text-anchor="middle">Period A: komplett davor</text>
+<line x1="411.5" y1="305" x2="429.5" y2="323" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="411.5" y1="323" x2="429.5" y2="305" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="581.0" y="327" width="160.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="661.0" y="368" font-size="11" fill="#444" text-anchor="middle">Period B: ueberlappt Grenze</text>
+<line x1="652.0" y1="305" x2="670.0" y2="323" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="652.0" y1="323" x2="670.0" y2="305" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="741.0" y="327" width="259.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="870.5" y="368" font-size="11" fill="#444" text-anchor="middle">Period C: komplett danach</text>
+<path d="M 861.5 314 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<line x1="30" y1="405" x2="1040" y2="405" stroke="#ddd" stroke-width="1"/>
+<text x="30" y="440" font-size="20" font-weight="700" fill="#111">lt</text>
+<text x="30" y="460" font-size="12.5" fill="#555">Overlap genuegt: Period muss nur vor die Grenze hineinragen.</text>
+<rect x="220" y="468" width="451.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="220" y1="476" x2="1040" y2="476" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,476 1033,472 1033,480" fill="#333"/>
+<line x1="671.0" y1="456" x2="671.0" y2="496" stroke="#c62828" stroke-width="2.5" />
+<text x="671.0" y="450" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="260" y="497" width="321.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="420.5" y="538" font-size="11" fill="#444" text-anchor="middle">Period A: komplett davor</text>
+<path d="M 411.5 484 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="581.0" y="497" width="160.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="661.0" y="538" font-size="11" fill="#444" text-anchor="middle">Period B: ueberlappt Grenze</text>
+<path d="M 652.0 484 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="741.0" y="497" width="259.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="870.5" y="538" font-size="11" fill="#444" text-anchor="middle">Period C: komplett danach</text>
+<line x1="861.5" y1="475" x2="879.5" y2="493" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="861.5" y1="493" x2="879.5" y2="475" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<text x="30" y="610" font-size="20" font-weight="700" fill="#111">eb</text>
+<text x="30" y="630" font-size="12.5" fill="#555">Vollstaendige Trennung noetig: Period muss komplett vor der Grenze liegen.</text>
+<rect x="220" y="638" width="451.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="220" y1="646" x2="1040" y2="646" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,646 1033,642 1033,650" fill="#333"/>
+<line x1="671.0" y1="626" x2="671.0" y2="666" stroke="#c62828" stroke-width="2.5" stroke-dasharray="4,4"/>
+<text x="671.0" y="620" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="260" y="667" width="321.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="420.5" y="708" font-size="11" fill="#444" text-anchor="middle">Period A: komplett davor</text>
+<path d="M 411.5 654 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="581.0" y="667" width="160.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="661.0" y="708" font-size="11" fill="#444" text-anchor="middle">Period B: ueberlappt Grenze</text>
+<line x1="652.0" y1="645" x2="670.0" y2="663" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="652.0" y1="663" x2="670.0" y2="645" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="741.0" y="667" width="259.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<text x="870.5" y="708" font-size="11" fill="#444" text-anchor="middle">Period C: komplett danach</text>
+<line x1="861.5" y1="645" x2="879.5" y2="663" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="861.5" y1="663" x2="879.5" y2="645" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+</svg>
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