feat: Adds hydronic system pressure calculator.

Sources/Styleguide/FormElements.swift

@@ -59,6 +59,17 @@ public struct Input: HTML, Sendable {
   }
 }
 
+public extension Input {
+
+  init<Key>(
+    id: Key,
+    name: String? = nil,
+    placeholder: String
+  ) where Key: RawRepresentable, Key.RawValue == String {
+    self.init(id: id.rawValue, name: name, placeholder: placeholder)
+  }
+}
+
 /// A style form input label.
 public struct InputLabel<InputLabel: HTML>: HTML {
 

Sources/Styleguide/ResultBox.swift

@@ -0,0 +1,17 @@
+import Elementary
+
+public struct ResultBox<Body: HTML>: HTML {
+  let body: Body
+
+  public init(@HTMLBuilder body: () -> Body) {
+    self.body = body()
+  }
+
+  public var content: some HTML<HTMLTag.div> {
+    div(.class("w-full rounded-lg shadow-lg bg-blue-100 border border-blue-600 text-blue-600 p-6")) {
+      body
+    }
+  }
+}
+
+extension ResultBox: Sendable where Body: Sendable {}

Sources/Styleguide/RoundedBox.swift

@@ -0,0 +1,18 @@
+import Elementary
+
+// A rounded box, with no color styles. Colors should be added at call site.
+public struct Box<Body: HTML>: HTML {
+  let body: Body
+
+  public init(@HTMLBuilder body: () -> Body) {
+    self.body = body()
+  }
+
+  public var content: some HTML<HTMLTag.div> {
+    div(.class("w-full rounded-lg shadow-lgp-6")) {
+      body
+    }
+  }
+}
+
+extension Box: Sendable where Body: Sendable {}

Sources/Styleguide/SVG.swift

@@ -45,6 +45,7 @@ public struct SVGSize: Sendable {
 public enum SVGType: Sendable, CaseIterable {
   case calculator
   case checkCircle
+  case circleGauge
   case droplets
   case exclamation
   case funnel
@@ -63,6 +64,7 @@ public enum SVGType: Sendable, CaseIterable {
     switch self {
     case .calculator: return calculatorSvg(size: size)
     case .checkCircle: return checkCircleSvg(size: size)
+    case .circleGauge: return circleGaugeSvg(size: size)
     case .droplets: return dropletsSvg(size: size)
     case .exclamation: return exclamationSvg(size: size)
     case .funnel: return funnelSvg(size: size)
@@ -84,6 +86,16 @@ public enum SVGType: Sendable, CaseIterable {
 
 // swiftlint:disable line_length
 
+private func circleGaugeSvg(size: SVGSize) -> HTMLRaw {
+  HTMLRaw("""
+  <svg xmlns="http://www.w3.org/2000/svg" width="\(size.width)" height="\(size.height)" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="lucide lucide-circle-gauge">
+  <path d="M15.6 2.7a10 10 0 1 0 5.7 5.7"/>
+  <circle cx="12" cy="12" r="2"/>
+  <path d="M13.4 10.6 19 5"/>
+  </svg>
+  """)
+}
+
 private func scaleSvg(size: SVGSize) -> HTMLRaw {
   HTMLRaw("""
   <svg xmlns="http://www.w3.org/2000/svg" width="\(size.width)" height="\(size.height)" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="lucide lucide-scale">