:root {
  --bg: #f3f6fb;
  --fg: #1a1a1a;
  --muted: #566370;
  --accent: #2a6df4;
  --border: #dbe3ec;
  --panel: #fafcfe;
  --panel-soft: #f6f8fb;
  --code-bg: #eef2f7;
  --accent-soft: #eaf1fb;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, sans-serif;
  line-height: 1.6;
}

header {
  border-bottom: 1px solid var(--border);
  background: var(--panel);
}

header .inner {
  max-width: 900px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
}

header h1 {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 600;
}

header h1 a {
  color: inherit;
  text-decoration: none;
}

header h1 a:hover {
  color: var(--accent);
}

header nav .auth-nav {
  margin-left: 1rem;
  font-size: 0.9rem;
  color: var(--muted);
  white-space: nowrap;
}

header nav .auth-nav a {
  color: var(--muted);
  text-decoration: none;
}

header nav .auth-nav a:hover {
  color: var(--accent);
}

.auth-user {
  font-weight: 600;
}

.auth-logout {
  display: inline;
  margin-left: 0.6rem;
}

.auth-logout button {
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
  font: inherit;
  padding: 0;
  text-decoration: underline;
}

.auth-logout button:hover {
  color: var(--accent);
}

main {
  max-width: 900px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

main h2 {
  margin-top: 0;
  font-size: 2rem;
  letter-spacing: -0.01em;
}

main p {
  color: var(--muted);
  font-size: 1.05rem;
}

main a {
  color: var(--accent);
}

.muted {
  color: var(--muted);
}

code, .eq {
  font-family: "Cambria Math", Cambria, Georgia, serif;
}

main p code, .result code, pre code, .submit-help code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
  background: var(--code-bg);
  padding: 0.05rem 0.3rem;
  border-radius: 3px;
}

/* Hero / question callout */
.hero {
  margin: 0 0 2rem;
  padding: 1.75rem 2rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: 4px;
}

.hero .lede {
  margin: 0;
  color: var(--fg);
  font-size: 1.25rem;
}

.hero .lede em {
  font-style: normal;
  font-weight: 600;
  color: var(--accent);
}

.eq-line {
  text-align: center;
  margin: 1rem 0 0;
}

.eq {
  font-size: 1.2rem;
  color: var(--fg);
}

.browse-cta {
  margin: 1.75rem 0;
  font-size: 1.1rem;
}

.browse-cta a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
}

.browse-cta a:hover {
  text-decoration: underline;
}

.page-nav {
  margin: 0 0 1rem;
  font-size: 0.95rem;
}

.page-nav a {
  color: var(--accent);
  text-decoration: none;
}

.page-nav a:hover {
  text-decoration: underline;
}

/* Submit / verify form */
.submit {
  margin-top: 3rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--border);
}

.submit h2 {
  font-size: 1.4rem;
}

.submit-help {
  color: var(--muted);
  font-size: 0.95rem;
  margin-top: 0.25rem;
}

.field {
  display: block;
  margin: 1.25rem 0;
}

.field > span {
  display: block;
  margin-bottom: 0.4rem;
  font-weight: 600;
  font-size: 0.95rem;
}

.field > span .muted {
  font-weight: 400;
}

.field input[type="text"],
.field textarea {
  width: 100%;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.95rem;
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--panel);
  resize: vertical;
  line-height: 1.5;
}

.field input[type="text"]:focus,
.field textarea:focus {
  outline: 2px solid var(--accent);
  outline-offset: -1px;
  border-color: transparent;
}

.submit-row {
  margin-top: 0.75rem;
}

.submit-row button {
  padding: 0.55rem 1.4rem;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 4px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
}

.submit-row button:hover {
  filter: brightness(1.08);
}

/* Verification result */
.result {
  padding: 1.25rem 1.5rem;
  border-radius: 4px;
  border: 1px solid var(--border);
  background: var(--panel);
  margin: 1rem 0;
}

.result h2 {
  margin-top: 0;
  font-size: 1.5rem;
}

.result-accepted {
  border-left: 4px solid #2a9d48;
}

.result-accepted h2 {
  color: #1d7a36;
}

.result-rejected {
  border-left: 4px solid #c0392b;
}

.result-rejected h2 {
  color: #a5281b;
}

.result-meta {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 0.3rem 1rem;
  margin: 1rem 0;
}

.result-meta dt {
  font-weight: 600;
}

.result-meta dd {
  margin: 0;
  min-width: 0;
  color: var(--muted);
  word-break: break-all;
}

.result-method {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 0;
}

.result-errors {
  margin: 0.5rem 0 0 1.25rem;
  color: var(--fg);
}

pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.75rem 1rem;
  overflow-x: auto;
  font-size: 0.9rem;
  line-height: 1.45;
}

pre code {
  background: transparent;
  padding: 0;
}

footer {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
  text-align: center;
}

footer a {
  color: var(--muted);
}

/* Wikipedia-style external-link glyph */
a.external::after {
  content: "";
  display: inline-block;
  width: 0.75em;
  height: 0.75em;
  margin-left: 0.25em;
  background-color: currentColor;
  opacity: 0.6;
  -webkit-mask: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12'><path d='M6 1h5v5L8.86 3.85 4.7 8 4 7.3l4.15-4.15zM2 3h2v1H3v6h6V8h1v3H2z'/></svg>") no-repeat center / contain;
          mask: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12'><path d='M6 1h5v5L8.86 3.85 4.7 8 4 7.3l4.15-4.15zM2 3h2v1H3v6h6V8h1v3H2z'/></svg>") no-repeat center / contain;
}

@media (max-width: 600px) {
  main { padding: 2rem 1.25rem; }
  .hero { padding: 1.25rem 1rem; }
  .eq { font-size: 1rem; word-break: break-word; }
  .result-meta { grid-template-columns: 1fr; gap: 0.1rem; }
  .result-meta dt { margin-top: 0.5rem; }
}