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

:root {
  --bg: #0f1117;
  --surface: #1a1b23;
  --surface-2: #22232e;
  --border: #2e2f3e;
  --text: #e1e2e8;
  --text-muted: #8b8d9e;
  --accent: #6c5ce7;
  --accent-hover: #7f71ed;
  --accent-bg: rgba(108, 92, 231, 0.1);
  --success: #00cec9;
  --error: #ff7675;
  --radius: 10px;
  --radius-sm: 6px;
  --font: 'SF Mono', 'Fira Code', 'Cascadia Code', 'JetBrains Mono', monospace;
  --font-ui: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

body {
  font-family: var(--font-ui);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}

.lang-switcher {
  display: flex;
  gap: 2px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.lang-btn {
  padding: 4px 10px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-family: var(--font-ui);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
}

.lang-btn:hover {
  color: var(--text);
  background: var(--accent-bg);
}

.lang-btn.active {
  color: #fff;
  background: var(--accent);
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  font-size: 1.6rem;
}

.logo h1 {
  font-family: var(--font);
  font-size: 1.4rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent), var(--success));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.tagline {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 24px;
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 24px;
  flex: 1;
  width: 100%;
}

.sidebar {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

nav {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--text-muted);
  font-family: var(--font-ui);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.15s ease;
  text-align: left;
  width: 100%;
  text-decoration: none;
}

.nav-btn:hover {
  background: var(--accent-bg);
  color: var(--text);
  border-color: var(--border);
}

.nav-btn.active {
  background: var(--accent-bg);
  color: var(--accent);
  border-color: var(--accent);
  font-weight: 600;
}

.nav-icon {
  font-family: var(--font);
  font-size: 0.7rem;
  font-weight: 700;
  min-width: 28px;
  text-align: center;
}

main {
  display: flex;
  flex-direction: column;
  gap: 24px;
  min-width: 0;
}

.tool-panel {
  display: none;
  flex-direction: column;
  gap: 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}

.tool-panel.active {
  display: flex;
}

.tool-panel h2 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.tool-desc {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.tool-options {
  display: flex;
  gap: 18px;
}

.tool-options label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  cursor: pointer;
  color: var(--text-muted);
}

.tool-options input[type="radio"] {
  accent-color: var(--accent);
}

textarea {
  width: 100%;
  min-height: 100px;
  padding: 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  color: var(--text);
  font-family: var(--font);
  font-size: 0.85rem;
  resize: vertical;
  transition: border-color 0.15s ease;
}

textarea:focus {
  outline: none;
  border-color: var(--accent);
}

textarea[readonly] {
  cursor: default;
  opacity: 0.9;
}

.btn-primary, .btn-secondary {
  padding: 10px 20px;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-ui);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
  align-self: flex-start;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

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

.btn-secondary {
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--border);
}

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

.btn-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.case-btns {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.btn-case {
  padding: 6px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  color: var(--text);
  font-family: var(--font);
  font-size: 0.78rem;
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-case:hover {
  border-color: var(--accent);
  background: var(--accent-bg);
}

.btn-case.active {
  border-color: var(--accent);
  background: var(--accent-bg);
  color: var(--accent);
}

.counter-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 12px;
}

.stat {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px;
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.stat-value {
  display: block;
  font-family: var(--font);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 2px;
}

.hash-results {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.hash-row {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 12px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
}

.hash-label {
  font-family: var(--font);
  font-weight: 600;
  min-width: 72px;
  color: var(--accent);
}

.hash-row code {
  font-family: var(--font);
  color: var(--text);
  word-break: break-all;
}

.uuid-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
}

.uuid-controls label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  color: var(--text-muted);
  cursor: pointer;
}

.uuid-controls select {
  padding: 4px 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  color: var(--text);
  font-family: var(--font-ui);
}

.uuid-controls input[type="checkbox"] {
  accent-color: var(--accent);
}

#json-status {
  font-size: 0.85rem;
  padding: 4px 0;
}

#json-status.error {
  color: var(--error);
}

#json-status.success {
  color: var(--success);
}

.ad-slot {
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--surface);
  border: 1px dashed var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.78rem;
  text-align: center;
  overflow: hidden;
}

.ad-sidebar {
  min-height: 200px;
  flex-shrink: 0;
  margin-top: auto;
}

.ad-bottom {
  min-height: 90px;
}

.ad-placeholder {
  padding: 20px;
}

footer {
  text-align: center;
  padding: 20px;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.82rem;
}

.share-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 4px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}

.share-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-right: 2px;
}

.share-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--surface-2);
  color: var(--text-muted);
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.15s ease;
  cursor: pointer;
  font-family: var(--font-ui);
}

.share-btn:hover {
  background: var(--accent-bg);
  color: var(--accent);
  border-color: var(--accent);
}

.share-twitter:hover {
  background: rgba(0, 0, 0, 0.15);
  color: #fff;
  border-color: #fff;
}

.share-linkedin:hover {
  background: rgba(10, 102, 194, 0.15);
  color: #0a66c2;
  border-color: #0a66c2;
}

.share-copy:hover {
  background: rgba(0, 206, 201, 0.15);
  color: var(--success);
  border-color: var(--success);
}

.tool-content {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-top: 8px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.content-section p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

.content-section h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--accent);
}

.content-section ol {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.8;
  padding-left: 20px;
}

.faq-item {
  margin-bottom: 14px;
  padding: 12px 16px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.faq-item h4 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 4px;
  color: var(--text);
}

.faq-item p {
  color: var(--text-muted);
  font-size: 0.85rem;
  line-height: 1.5;
  margin: 0;
}

@media (max-width: 768px) {
  .container {
    grid-template-columns: 1fr;
    padding: 16px;
  }

  .sidebar {
    flex-direction: row;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  nav {
    flex-direction: row;
    gap: 4px;
    flex-wrap: nowrap;
  }

  .nav-btn {
    white-space: nowrap;
    padding: 8px 12px;
    font-size: 0.8rem;
  }

  .nav-icon {
    min-width: auto;
  }

  .ad-sidebar {
    display: none;
  }

  .header-inner {
    padding: 12px 16px;
  }
}