Add hub landing logo SVG and watermark background.

Globe with mercator grid, rocket arc, and palette aligned to crash console;
hub.css at 3% opacity background; styles split from inline HTML.

Co-authored-by: Cursor <cursoragent@cursor.com>

examples/app_hub/hub.css

@@ -0,0 +1,192 @@
+/* Project hub — matches crash console tokens (app.css) */
+
+.hub-page {
+  min-height: 100vh;
+  display: flex;
+  flex-direction: column;
+  position: relative;
+  isolation: isolate;
+}
+
+/* 97% transparent watermark */
+.hub-page::before {
+  content: "";
+  position: fixed;
+  inset: 0;
+  z-index: 0;
+  pointer-events: none;
+  background: url("assets/hub-logo.svg") center center / min(92vmin, 960px) no-repeat;
+  opacity: 0.03;
+}
+
+[data-theme="light"] .hub-page::before {
+  opacity: 0.035;
+}
+
+.hub-shell {
+  flex: 1;
+  min-height: calc(100vh - 40px);
+  position: relative;
+  z-index: 1;
+}
+
+.hub-main {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  min-height: calc(100vh - 40px);
+  padding: 32px 28px 48px;
+  box-sizing: border-box;
+}
+
+.hub-header {
+  text-align: center;
+  margin-bottom: 36px;
+}
+
+.hub-brand {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 12px;
+  margin-bottom: 8px;
+}
+
+.hub-logo-mark {
+  width: 56px;
+  height: 42px;
+  color: var(--accent);
+}
+
+.hub-title {
+  margin: 0 0 8px;
+  font-size: 1.75rem;
+  font-weight: 600;
+  letter-spacing: -0.02em;
+}
+
+.hub-subtitle {
+  margin: 0 0 16px;
+}
+
+.hub-theme {
+  justify-content: center;
+}
+
+.hub-cards {
+  display: grid;
+  grid-template-columns: repeat(3, minmax(200px, 1fr));
+  gap: 24px;
+  width: 100%;
+  max-width: 1080px;
+  margin: 0;
+}
+
+.hub-card {
+  display: flex;
+  flex-direction: row;
+  align-items: center;
+  gap: 14px;
+  padding: 22px 24px;
+  color: var(--text);
+  text-decoration: none;
+  cursor: pointer;
+}
+
+.hub-card:hover,
+.hub-card:focus-visible {
+  color: var(--text);
+  text-decoration: none;
+  outline: none;
+}
+
+.hub-cards .hub-card {
+  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
+}
+
+.hub-cards .hub-card:hover,
+.hub-cards .hub-card:focus-visible {
+  transform: translateY(-10px);
+  box-shadow: 0 20px 48px rgba(0, 0, 0, 0.44);
+  border-color: var(--accent);
+}
+
+[data-theme="light"] .hub-cards .hub-card:hover,
+[data-theme="light"] .hub-cards .hub-card:focus-visible {
+  box-shadow: 0 20px 44px rgba(26, 35, 50, 0.28);
+}
+
+.hub-card-icon {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  flex-shrink: 0;
+  width: 40px;
+  height: 40px;
+  color: var(--accent);
+}
+
+.hub-card-icon .nav-icon {
+  position: relative;
+}
+
+.hub-card-label {
+  font-size: 14px;
+  font-weight: 500;
+  line-height: 1.25;
+  text-align: left;
+}
+
+.nav-icon--git {
+  width: 18px;
+  height: 18px;
+}
+
+.nav-icon--git::before {
+  content: "";
+  position: absolute;
+  left: 2px;
+  top: 2px;
+  width: 7px;
+  height: 7px;
+  border: 2px solid currentColor;
+  border-radius: 50%;
+  box-sizing: border-box;
+}
+
+.nav-icon--git::after {
+  content: "";
+  position: absolute;
+  left: 8px;
+  top: 5px;
+  width: 10px;
+  height: 10px;
+  border: 2px solid currentColor;
+  border-left: none;
+  border-bottom: none;
+  border-radius: 0 6px 0 0;
+  box-sizing: border-box;
+}
+
+.hub-page .bottom-bar {
+  position: relative;
+  z-index: 1;
+}
+
+@media (max-width: 860px) {
+  .hub-cards {
+    grid-template-columns: 1fr;
+    max-width: 420px;
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .hub-cards .hub-card {
+    transition: border-color 0.15s ease, box-shadow 0.15s ease;
+  }
+  .hub-cards .hub-card:hover,
+  .hub-cards .hub-card:focus-visible {
+    transform: none;
+  }
+}