style: convert project sizing to scalable rem units with responsive root font scaling

src/styles/globals.css

@@ -16,10 +16,23 @@
 }
 
 html {
+  font-size: 100%;
   scroll-behavior: smooth;
   color-scheme: light;
 }
 
+@media (max-width: 1024px) {
+  html {
+    font-size: 93.75%;
+  }
+}
+
+@media (max-width: 650px) {
+  html {
+    font-size: 87.5%;
+  }
+}
+
 html[data-theme="dark"] {
   color-scheme: dark;
 }
@@ -56,7 +69,7 @@ body {
   }
 }
 
-/* 1320px Inner Content Container with 60px Gutters */
+/* 1320px Inner Content Container with Page Gutters */
 .content-container {
   width: calc(100% - (2 * var(--layout-page-gutter)));
   max-width: var(--layout-container);
@@ -64,18 +77,18 @@ body {
   position: relative;
 }
 
-@media (max-width: 640px) {
+@media (max-width: 650px) {
   .section-header {
     margin-bottom: var(--space-6);
   }
 
   .section-title {
-    font-size: 28px;
-    line-height: 38px;
+    font-size: 1.75rem;
+    line-height: 2.375rem;
   }
 
   .section-underline {
-    width: 88px;
+    width: 5.5rem;
   }
 }
 
@@ -84,7 +97,7 @@ body {
   display: flex;
   flex-direction: column;
   align-items: flex-start;
-  margin-bottom: 40px;
+  margin-bottom: 2.5rem;
 }
 
 .section-eyebrow {
@@ -94,7 +107,7 @@ body {
   text-transform: uppercase;
   font-weight: 700;
   color: var(--text-secondary);
-  margin-bottom: 8px;
+  margin-bottom: 0.5rem;
 }
 
 .section-title-wrap {
@@ -108,11 +121,11 @@ body {
   line-height: var(--line-height-h2);
   font-weight: 700;
   color: var(--text-primary);
-  margin-bottom: 12px;
+  margin-bottom: 0.75rem;
 }
 
 .section-underline {
-  width: 120px;
+  width: 7.5rem;
   height: 3px;
   background-color: var(--accent-default);
   border-radius: var(--radius-pill);
@@ -129,9 +142,9 @@ body {
   display: inline-flex;
   align-items: center;
   justify-content: center;
-  gap: 8px;
+  gap: 0.5rem;
   height: var(--size-button-height);
-  padding: 0 24px;
+  padding: 0 1.5rem;
   border-radius: var(--radius-pill);
   font-size: var(--font-size-button);
   line-height: var(--line-height-button);