:root {
  --bg: #ffffff;
  --bg-secondary: #f5f5f7;
  --bg-tertiary: #e8e8ed;
  --text: #1d1d1f;
  --text-secondary: #6e6e73;
  --border: #d2d2d7;
  --accent: #0071e3;
  --accent-hover: #0077ed;
  --error: #ff3b30;
  --error-bg: #fff0f0;
  --warning: #ff9500;
  --warning-bg: #fff8f0;
  --info: #007aff;
  --info-bg: #f0f5ff;
  --success: #34c759;
  --success-bg: #f0fff4;
  --code-bg: #f5f5f7;
  --radius: 8px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
  --font-mono: "SF Mono", "Menlo", "Consolas", monospace;
  --font-sans:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1c1c1e;
    --bg-secondary: #2c2c2e;
    --bg-tertiary: #3a3a3c;
    --text: #f5f5f7;
    --text-secondary: #98989d;
    --border: #48484a;
    --error-bg: #3a1c1c;
    --warning-bg: #3a2e1c;
    --info-bg: #1c2a3a;
    --success-bg: #1c3a24;
    --code-bg: #2c2c2e;
  }
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
}

.container {
  max-width: 860px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

header {
  text-align: center;
  margin-bottom: 2rem;
}

header .logo {
  width: 80px;
  height: 80px;
  margin-bottom: 0.75rem;
  border-radius: 16px;
  box-shadow: var(--shadow);
}

header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

header p {
  color: var(--text-secondary);
  margin-top: 0.25rem;
  font-size: 0.95rem;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1rem;
}

.tab-btn {
  padding: 0.6rem 1.2rem;
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  transition:
    color 0.15s,
    border-color 0.15s;
}

.tab-btn:hover {
  color: var(--text);
}

.tab-btn.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.tab-panel {
  display: none;
}

.tab-panel.active {
  display: block;
}

/* Input areas */
textarea {
  width: 100%;
  min-height: 240px;
  padding: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  background: var(--bg-secondary);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  resize: vertical;
  line-height: 1.6;
}

textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(0, 113, 227, 0.15);
}

.input-row {
  display: flex;
  gap: 0.75rem;
  align-items: center;
}

.input-row input[type="text"] {
  flex: 1;
  padding: 0.6rem 0.75rem;
  font-size: 0.9rem;
  background: var(--bg-secondary);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.input-row input[type="text"]:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(0, 113, 227, 0.15);
}

input[type="file"] {
  font-size: 0.9rem;
}

.btn {
  padding: 0.6rem 1.4rem;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  white-space: nowrap;
  transition: background 0.15s;
}

.btn:hover {
  background: var(--accent-hover);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.actions {
  margin-top: 0.75rem;
}

/* Results */
#results {
  margin-top: 2rem;
}

.banner {
  padding: 0.75rem 1rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 1rem;
}

.banner.valid {
  background: var(--success-bg);
  color: var(--success);
  border: 1px solid var(--success);
}

.banner.invalid {
  background: var(--error-bg);
  color: var(--error);
  border: 1px solid var(--error);
}

.summary {
  color: var(--text-secondary);
  font-size: 0.85rem;
  margin-bottom: 1rem;
}

.section {
  margin-bottom: 1.25rem;
}

.section-header {
  font-weight: 600;
  font-size: 0.9rem;
  padding: 0.5rem 0;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  user-select: none;
}

.section-header::before {
  content: "\25B6";
  font-size: 0.6rem;
  transition: transform 0.15s;
}

.section-header.open::before {
  transform: rotate(90deg);
}

.section-header.errors {
  color: var(--error);
}

.section-header.warnings {
  color: var(--warning);
}

.section-header.infos {
  color: var(--info);
}

.section-body {
  display: none;
}

.section-body.open {
  display: block;
}

.diagnostic {
  padding: 0.6rem 0.75rem;
  margin: 0.35rem 0;
  border-radius: var(--radius);
  font-size: 0.85rem;
  border-left: 3px solid;
}

.diagnostic.error {
  background: var(--error-bg);
  border-left-color: var(--error);
}

.diagnostic.warning {
  background: var(--warning-bg);
  border-left-color: var(--warning);
}

.diagnostic.info {
  background: var(--info-bg);
  border-left-color: var(--info);
}

.diagnostic .diag-header {
  display: flex;
  gap: 0.5rem;
  align-items: baseline;
  flex-wrap: wrap;
}

.diagnostic .diag-id {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.8rem;
}

.diagnostic .diag-location {
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.diagnostic .diag-message {
  margin-top: 0.2rem;
}

.diagnostic .diag-path {
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  margin-top: 0.15rem;
}

.diagnostic .diag-fix {
  color: var(--accent);
  font-size: 0.8rem;
  margin-top: 0.2rem;
}

.cors-note {
  color: var(--text-secondary);
  font-size: 0.8rem;
  margin-top: 0.4rem;
}

footer {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.8rem;
}

footer a {
  color: var(--accent);
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

footer code {
  background: var(--code-bg);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

footer .disclaimer {
  margin-top: 0.5rem;
  font-size: 0.7rem;
  color: var(--text-secondary);
}