Construction WBS

digraph wbs {
  rankdir=TB;
  graph [bgcolor=transparent];
  node [shape=box, style="rounded,filled", fontname=Inter, fontsize=10];

  Proj [label="1. Commercial Building", fillcolor="#fce7f3"];
  P1 [label="1.1 Preconstruction"]; P2 [label="1.2 Site"]; P3 [label="1.3 Structure"];
  P4 [label="1.4 Envelope"]; P5 [label="1.5 MEP"]; P6 [label="1.6 Interior"];
  P7 [label="1.7 Closeout"];

  P1a [label="Design + permits"];
  P2a [label="Survey + demo"]; P2b [label="Excavation"]; P2c [label="Utilities"];
  P3a [label="Foundation"]; P3b [label="Steel frame"]; P3c [label="Slabs"];
  P4a [label="Curtain wall"]; P4b [label="Roof"];
  P5a [label="HVAC"]; P5b [label="Plumbing"]; P5c [label="Electrical"];
  P6a [label="Drywall + paint"]; P6b [label="Floors"]; P6c [label="Fixtures"];
  P7a [label="Commissioning"]; P7b [label="Punch list"];

  Proj -> P1 -> P1a;
  Proj -> P2; P2 -> P2a; P2 -> P2b; P2 -> P2c;
  Proj -> P3; P3 -> P3a; P3 -> P3b; P3 -> P3c;
  Proj -> P4; P4 -> P4a; P4 -> P4b;
  Proj -> P5; P5 -> P5a; P5 -> P5b; P5 -> P5c;
  Proj -> P6; P6 -> P6a; P6 -> P6b; P6 -> P6c;
  Proj -> P7; P7 -> P7a; P7 -> P7b;
}