fix: migrate inline styles to CSS modules per review feedback

web/src/pages/RegisterPage.module.css

@@ -0,0 +1,120 @@
+.container {
+  min-height: 100vh;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background-color: #f5f5f5;
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
+}
+
+.card {
+  background-color: #fff;
+  padding: 2rem;
+  border-radius: 8px;
+  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+  width: 100%;
+  max-width: 440px;
+}
+
+.title {
+  margin: 0 0 0.25rem;
+  font-size: 1.5rem;
+  font-weight: 600;
+}
+
+.subtitle {
+  margin: 0 0 1.5rem;
+  color: #666;
+  font-size: 0.9rem;
+}
+
+.form {
+  display: flex;
+  flex-direction: column;
+  gap: 1rem;
+}
+
+.row {
+  display: flex;
+  gap: 0.75rem;
+}
+
+.field {
+  display: flex;
+  flex-direction: column;
+  gap: 0.35rem;
+}
+
+.halfField {
+  display: flex;
+  flex-direction: column;
+  gap: 0.35rem;
+  flex: 1;
+}
+
+.label {
+  font-size: 0.85rem;
+  font-weight: 500;
+  color: #333;
+}
+
+.required {
+  color: #b91c1c;
+}
+
+.input {
+  padding: 0.6rem 0.75rem;
+  border: 1px solid #ccc;
+  border-radius: 6px;
+  font-size: 0.95rem;
+  outline: none;
+  transition: border-color 0.15s;
+}
+
+.input:focus {
+  border-color: #1a73e8;
+}
+
+.button {
+  padding: 0.65rem;
+  background-color: #1a73e8;
+  color: #fff;
+  border: none;
+  border-radius: 6px;
+  font-size: 1rem;
+  font-weight: 500;
+  cursor: pointer;
+  margin-top: 0.5rem;
+}
+
+.button:disabled {
+  opacity: 0.6;
+  cursor: not-allowed;
+}
+
+.error {
+  background-color: #fef2f2;
+  color: #b91c1c;
+  border: 1px solid #fecaca;
+  border-radius: 6px;
+  padding: 0.5rem 0.75rem;
+  font-size: 0.85rem;
+  margin-bottom: 0.5rem;
+}
+
+.footer {
+  margin-top: 1.25rem;
+  text-align: center;
+  font-size: 0.85rem;
+  color: #666;
+}
+
+.link {
+  color: #1a73e8;
+  text-decoration: none;
+  font-weight: 500;
+}
+
+.link:hover {
+  text-decoration: underline;
+}