:root[data-theme='light'] {
  --bg-primary: #f9fafb;
  --bg-secondary: rgba(255, 255, 255, 0.85);
  --bg-gradient: linear-gradient(160deg, #edf2ff 0%, #f8fafc 42%, #e0f2fe 100%);
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --border-light: rgba(255, 255, 255, 0.4);
  --accent-primary: #0284c7;
  --accent-success: #16a34a;
  --accent-warning: #d97706;
  --accent-danger: #dc2626;
  --accent-purple: #7c3aed;
  --shadow-sm: 0 4px 6px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 20px 25px rgba(0, 0, 0, 0.04);
}

:root[data-theme='dark'] {
  --bg-primary: #0f172a;
  --bg-secondary: rgba(20, 25, 45, 0.95);
  --bg-gradient: linear-gradient(160deg, #1a2942 0%, #1f2937 42%, #1a3f5c 100%);
  --text-primary: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --border-light: rgba(255, 255, 255, 0.1);
  --accent-primary: #38bdf8;
  --accent-success: #22c55e;
  --accent-warning: #f59e0b;
  --accent-danger: #ef4444;
  --accent-purple: #a78bfa;
  --shadow-sm: 0 4px 6px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 20px 25px rgba(0, 0, 0, 0.3);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--bg-gradient);
  color: var(--text-primary);
  min-height: 100vh;
  padding: 20px;
  transition: background-color 0.3s ease;
}

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800;900&display=swap');

.container {
  max-width: 900px;
  margin: 0 auto;
}

.header {
  text-align: center;
  margin-bottom: 50px;
  margin-top: 20px;
}

.subtitle {
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent-primary);
  margin-bottom: 12px;
  font-weight: 700;
  font-kerning: auto;
}

h1 {
  font-size: 3.5rem;
  font-weight: 900;
  margin-bottom: 16px;
  color: var(--text-primary);
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.description {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.65;
  font-weight: 400;
}

.form-section {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 20px;
  padding: 40px;
  backdrop-filter: blur(8px);
  margin-bottom: 40px;
  box-shadow: var(--shadow-md);
}

.form-group {
  display: flex;
  flex-direction: column;
  margin-bottom: 24px;
}

.form-group label {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-secondary);
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.form-group input {
  padding: 12px 16px;
  font-size: 15px;
  border: 1px solid;
  border-color: var(--text-muted);
  border-radius: 12px;
  background: transparent;
  color: var(--text-primary);
  font-family: inherit;
}

.form-group input::placeholder {
  color: var(--text-muted);
}

.form-group input:focus {
  outline: none;
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.15);
}

.form-group textarea,
.form-group select {
  padding: 12px 16px;
  font-size: 15px;
  border: 1px solid var(--text-muted);
  border-radius: 12px;
  background: transparent;
  color: var(--text-primary);
  font-family: inherit;
  resize: vertical;
}

.form-group textarea::placeholder,
.form-group select::placeholder {
  color: var(--text-muted);
}

.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.15);
}

.form-group select {
  cursor: pointer;
  appearance: none;
  background-image: url('data:image/svg+xml;utf8,<svg fill="%23999" height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"><path d="M7 10l5 5 5-5z"/></svg>');
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 20px;
  padding-right: 40px;
}

.form-row .form-group {
  margin-bottom: 0;
}

.form-row {
  display: grid;
  grid-template-columns: 150px 150px 150px;
  gap: 20px;
  align-items: flex-end;
}

.form-row .btn-primary {
  align-self: flex-end;
  height: fit-content;
  padding: 12px 24px;
}

@media (max-width: 600px) {
  .form-row {
    grid-template-columns: 1fr;
  }
}

.btn-primary {
  padding: 12px 24px;
  font-size: 14px;
  font-weight: 700;
  background: var(--text-primary);
  color: var(--bg-primary);
  border: none;
  border-radius: 12px;
  cursor: pointer;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-family: inherit;
}

.btn-primary:hover:not(:disabled) {
  opacity: 0.85;
}

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

.form-hint {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 12px;
}

.error-msg {
  color: var(--accent-danger);
  font-size: 14px;
  margin-top: 12px;
  padding: 12px;
  background: rgba(220, 38, 38, 0.1);
  border-radius: 8px;
  display: none;
}

.error-msg.show {
  display: block;
}

.results-section {
  display: contents;
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin-bottom: 30px;
}

.metric-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 24px;
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-md);
}

.metric-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--text-muted);
  margin-bottom: 10px;
  font-weight: 700;
}

.metric-value {
  font-size: 32px;
  font-weight: 900;
  margin-bottom: 8px;
  line-height: 1;
}

.metric-value.value-blue {
  color: var(--accent-primary);
}

.metric-value.value-green {
  color: var(--accent-success);
}

.metric-value.value-amber {
  color: var(--accent-warning);
}

.metric-value.value-purple {
  color: var(--accent-purple);
}

.metric-value.value-red {
  color: var(--accent-danger);
}

.metric-hint {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.4;
}

.insights-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 28px;
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-md);
}

.insights-box h2 {
  font-size: 18px;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.insights-box ul {
  list-style: disc;
  margin-left: 20px;
  line-height: 1.8;
  color: var(--text-secondary);
}

.insights-box li {
  margin-bottom: 12px;
  font-weight: 400;
}

.stability-text {
  margin-top: 16px;
  font-size: 13px;
  color: var(--text-muted);
}

.requests-table-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 28px;
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-md);
  margin-top: 20px;
}

.requests-table-box h2 {
  font-size: 18px;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 20px;
  letter-spacing: -0.01em;
}

.requests-table-wrapper {
  overflow-x: auto;
  border-radius: 12px;
}

.requests-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.requests-table thead {
  background: rgba(0, 0, 0, 0.03);
  border-bottom: 1px solid var(--border-light);
}

.requests-table th {
  padding: 12px 16px;
  text-align: left;
  font-weight: 700;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 12px;
}

.requests-table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-secondary);
}

.requests-table tbody tr:hover {
  background: rgba(0, 0, 0, 0.02);
}

.requests-table tbody tr:last-child td {
  border-bottom: none;
}

.request-status-code {
  font-weight: 600;
  font-family: 'Courier New', monospace;
}

.request-status-code.success {
  color: var(--accent-success);
}

.request-status-code.error {
  color: var(--accent-danger);
}

.request-latency {
  font-weight: 600;
  color: var(--text-primary);
}

.request-result {
  font-weight: 600;
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: 0.06em;
}

.request-result.success {
  color: var(--accent-success);
}

.request-result.error {
  color: var(--accent-danger);
}

.export-box {
  margin-top: 0;
  margin-bottom: 20px;
  padding: 24px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 12px;
}

.export-box h2 {
  margin-top: 0;
  margin-bottom: 16px;
  font-size: 18px;
  color: var(--text-primary);
}

.export-buttons {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn-export {
  padding: 10px 16px;
  font-size: 14px;
  font-weight: 600;
  border: 1px solid var(--text-muted);
  border-radius: 8px;
  background: var(--bg-primary);
  color: var(--text-primary);
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-export:hover {
  background: var(--accent-primary);
  color: white;
  border-color: var(--accent-primary);
}

.btn-export:active {
  transform: scale(0.98);
}

.site-footer {
  margin-top: 40px;
  margin-bottom: -20px;
  padding: 32px 20px;
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  border-top: 1px solid var(--border-light);
  margin-left: -20px;
  margin-right: -20px;
}

.footer-content {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.footer-left {
  flex: 1;
}

.footer-credit {
  margin: 0;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 500;
  line-height: 1.6;
}

.footer-copyright {
  margin: 6px 0 0 0;
  color: var(--text-muted);
  font-size: 12px;
  line-height: 1.5;
}

.footer-content a {
  color: var(--accent-primary);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.footer-content a:hover {
  color: #0369a1;
}

.footer-nav {
  display: flex;
  gap: 24px;
}

.footer-link {
  color: var(--accent-primary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s ease;
}

.footer-link:hover {
  color: #0369a1;
}

.about-page {
  margin-top: 20px;
  margin-bottom: 20px;
}

.about-hero,
.about-section,
.about-actions {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 24px;
  box-shadow: var(--shadow-md);
}

.about-hero,
.about-section {
  margin-bottom: 18px;
}

.about-hero {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.about-back-btn {
  display: inline-block;
  margin-top: 16px;
  padding: 10px 20px;
  background-color: var(--accent-primary);
  color: white;
  text-decoration: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: opacity 0.2s ease;
}

.about-back-btn:hover {
  opacity: 0.9;
}

.about-section h2 {
  font-size: 20px;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.about-section h3 {
  font-size: 16px;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.about-section p,
.about-section li,
.about-note {
  color: var(--text-secondary);
  line-height: 1.65;
}

.about-section ul,
.about-section ol {
  margin-left: 20px;
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.about-card {
  border: 1px solid var(--border-light);
  border-radius: 12px;
  padding: 14px;
  background: rgba(255, 255, 255, 0.25);
}

.about-actions {
  display: flex;
  justify-content: flex-start;
}

@media (max-width: 768px) {
  h1 {
    font-size: 2.2rem;
  }

  .form-section {
    padding: 24px;
  }

  .metrics-grid {
    grid-template-columns: 1fr 1fr;
  }

  .footer-content {
    flex-direction: column;
    align-items: flex-start;
  }
}