:root {
  --bg: #0a0a0b;
  --bg2: #111114;
  --bg3: #1a1a1f;
  --text: #e4e4e7;
  --text2: #a1a1aa;
  --text3: #71717a;
  --accent: #3b82f6;
  --accent2: #2563eb;
  --green: #22c55e;
  --red: #ef4444;
  --yellow: #eab308;
  --border: #27272a;
  --radius: 12px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent2); }

/* Header */
.header {
  border-bottom: 1px solid var(--border);
  background: var(--bg2);
  position: sticky; top: 0; z-index: 100;
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 60px;
}
.logo {
  display: flex; align-items: center; gap: 8px;
  font-weight: 700; font-size: 18px; color: var(--text);
}
.logo-icon { font-size: 24px; }
.nav { display: flex; gap: 24px; }
.nav a { color: var(--text2); font-size: 14px; font-weight: 500; }
.nav a:hover { color: var(--text); }

/* Hero */
.hero {
  text-align: center;
  padding: 80px 24px 60px;
}
.hero h1 {
  font-size: 48px; font-weight: 800;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
}
.hero-sub {
  font-size: 20px; color: var(--text2); margin-bottom: 24px;
}
.privacy-badge {
  display: inline-flex; align-items: center; gap: 8px;
  background: rgba(34,197,94,0.1); color: var(--green);
  padding: 8px 20px; border-radius: 999px; font-size: 14px; font-weight: 500;
  border: 1px solid rgba(34,197,94,0.2);
}
.badge-icon { font-size: 16px; }

/* Tools Grid */
.tools-section { padding: 60px 0; }
.tools-section h2 { font-size: 28px; margin-bottom: 32px; }
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.tool-card {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: all 0.2s;
  position: relative;
  display: block; color: var(--text);
}
.tool-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(59,130,246,0.1);
  color: var(--text);
}
.tool-icon {
  font-size: 28px; font-weight: 700;
  color: var(--accent);
  margin-bottom: 12px;
  font-family: 'SF Mono', 'Fira Code', monospace;
}
.tool-card h3 { font-size: 16px; margin-bottom: 8px; }
.tool-card p { font-size: 13px; color: var(--text2); line-height: 1.5; }
.tool-tag {
  position: absolute; top: 12px; right: 12px;
  background: rgba(59,130,246,0.15); color: var(--accent);
  font-size: 11px; font-weight: 600; padding: 2px 8px;
  border-radius: 4px; text-transform: uppercase;
}

/* About */
.about-section { padding: 60px 0; border-top: 1px solid var(--border); }
.about-section h2 { font-size: 28px; margin-bottom: 32px; text-align: center; }
.features-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 24px;
}
.feature {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}
.feature h3 { font-size: 16px; margin-bottom: 8px; }
.feature p { font-size: 13px; color: var(--text2); }

/* Footer */
.footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  text-align: center;
  color: var(--text3);
  font-size: 13px;
}

/* ===== Tool Page Styles ===== */

.tool-page {
  padding: 32px 0 80px;
}
.tool-header {
  display: flex; align-items: center; gap: 16px;
  margin-bottom: 24px; flex-wrap: wrap;
}
.tool-header h1 { font-size: 28px; font-weight: 700; }
.tool-header .back-link {
  display: inline-flex; align-items: center; gap: 4px;
  color: var(--text3); font-size: 14px;
}
.tool-header .back-link:hover { color: var(--accent); }
.privacy-note {
  display: flex; align-items: center; gap: 6px;
  color: var(--green); font-size: 13px;
  margin-left: auto;
}

.tool-area {
  display: grid; gap: 20px;
}
.tool-area.split {
  grid-template-columns: 1fr 1fr;
}
@media (max-width: 768px) {
  .tool-area.split { grid-template-columns: 1fr; }
  .hero h1 { font-size: 32px; }
}

textarea, input[type="text"] {
  width: 100%;
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  font-size: 13px;
  padding: 16px;
  resize: vertical;
  outline: none;
  transition: border-color 0.2s;
}
textarea:focus, input[type="text"]:focus {
  border-color: var(--accent);
}
textarea { min-height: 200px; }

.btn-group {
  display: flex; gap: 8px; flex-wrap: wrap; margin: 12px 0;
}
.btn {
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg2);
  color: var(--text);
  font-size: 13px; font-weight: 500;
  cursor: pointer;
  transition: all 0.15s;
}
.btn:hover { border-color: var(--accent); color: var(--accent); }
.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.btn-primary:hover { background: var(--accent2); border-color: var(--accent2); color: #fff; }

.output-area {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 13px;
  white-space: pre-wrap;
  word-break: break-all;
  min-height: 200px;
  overflow: auto;
  color: var(--text);
}

.error-msg {
  color: var(--red);
  font-size: 13px;
  margin-top: 8px;
  display: none;
  background: rgba(239,68,68,0.08);
  border: 1px solid rgba(239,68,68,0.2);
  border-radius: 8px;
  padding: 10px 14px;
  line-height: 1.6;
}
.error-msg.show { display: block; }
.error-msg .error-title {
  font-weight: 600;
  display: block;
  margin-bottom: 4px;
}
.error-msg .error-position {
  font-family: 'SF Mono', 'Fira Code', monospace;
  background: rgba(239,68,68,0.12);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 12px;
  margin: 0 2px;
}
.error-msg .error-snippet {
  display: block;
  margin-top: 6px;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 12px;
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 12px;
  white-space: pre;
  overflow-x: auto;
  color: var(--text2);
  line-height: 1.7;
}
.error-msg .error-pointer {
  color: var(--red);
  font-weight: 700;
}

textarea.error-at-position {
  border-color: var(--red) !important;
  box-shadow: 0 0 0 2px rgba(239,68,68,0.25);
}

.success-msg {
  color: var(--green);
  font-size: 13px;
  margin-top: 8px;
  display: none;
}
.success-msg.show { display: block; }

label {
  display: block; font-size: 13px; font-weight: 500;
  color: var(--text2); margin-bottom: 6px;
}

select {
  padding: 8px 12px;
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-size: 13px;
  outline: none;
}

.checkbox-label {
  display: flex; align-items: center; gap: 8px;
  font-size: 13px; color: var(--text2); cursor: pointer;
}
.checkbox-label input[type="checkbox"] { width: 16px; height: 16px; }

.result-section h3 {
  font-size: 14px; font-weight: 500; color: var(--text2); margin-bottom: 8px;
}

.copy-btn {
  float: right; font-size: 12px;
}

/* JWT specific */
.jwt-section {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  margin-top: 12px;
}
.jwt-section h3 {
  font-size: 14px; margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}
.jwt-section pre {
  font-size: 12px;
  white-space: pre-wrap;
  word-break: break-all;
}

/* Timestamp */
.current-ts {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  text-align: center;
  margin-bottom: 20px;
}
.current-ts .ts-value {
  font-size: 32px; font-weight: 700;
  font-family: 'SF Mono', monospace;
  color: var(--accent);
}
.current-ts .ts-label {
  font-size: 12px; color: var(--text3);
}

/* Diff */
.diff-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
@media (max-width: 768px) {
  .diff-container { grid-template-columns: 1fr; }
}
.diff-output {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  font-family: monospace;
  font-size: 13px;
  white-space: pre-wrap;
  overflow: auto;
  min-height: 200px;
}
.diff-add { background: rgba(34,197,94,0.15); color: var(--green); }
.diff-del { background: rgba(239,68,68,0.15); color: var(--red); }

/* Color tool */
.color-preview {
  width: 100%;
  height: 80px;
  border-radius: 8px;
  border: 1px solid var(--border);
  margin-bottom: 16px;
}
.color-values {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
}
.color-value-item {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
}
.color-value-item label { margin-bottom: 0; }
.color-value-item code {
  display: block;
  font-size: 14px;
  margin-top: 4px;
  color: var(--accent);
  word-break: break-all;
  overflow-wrap: break-word;
}

/* UUID */
.uuid-list {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  font-family: monospace;
  font-size: 13px;
}
.uuid-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 6px 0;
  border-bottom: 1px solid var(--border);
}
.uuid-item:last-child { border-bottom: none; }

/* Markdown */
.md-preview {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px;
  min-height: 300px;
  line-height: 1.8;
}
.md-preview h1, .md-preview h2, .md-preview h3 { margin: 16px 0 8px; }
.md-preview p { margin: 8px 0; }
.md-preview code {
  background: var(--bg3); padding: 2px 6px;
  border-radius: 4px; font-size: 12px;
}
.md-preview pre {
  background: var(--bg3); padding: 12px;
  border-radius: 8px; overflow-x: auto;
  margin: 8px 0;
}
.md-preview blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 16px; color: var(--text2);
}
.md-preview ul, .md-preview ol { padding-left: 24px; margin: 8px 0; }
.md-preview a { color: var(--accent); }

/* File upload area */
.upload-area {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 8px;
  padding: 10px 14px;
  background: var(--bg3);
  border: 1px dashed var(--border);
  border-radius: 8px;
  transition: all 0.2s;
}
.upload-area.upload-drag-over {
  border-color: var(--accent);
  background: rgba(59,130,246,0.08);
  box-shadow: 0 0 0 2px rgba(59,130,246,0.25);
}
.btn-upload {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--accent) !important;
  border-color: var(--accent) !important;
  color: #fff !important;
  font-size: 13px;
  font-weight: 600;
  padding: 6px 14px !important;
  border-radius: 6px;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.15s;
}
.btn-upload:hover {
  background: var(--accent2) !important;
  border-color: var(--accent2) !important;
  color: #fff !important;
}
.upload-icon {
  font-size: 14px;
  line-height: 1;
}
.upload-hint {
  font-size: 12px;
  color: var(--text3);
  user-select: none;
}

/* File upload drag-over */
textarea.drag-over {
  border-color: var(--accent);
  background: rgba(59,130,246,0.08);
  box-shadow: 0 0 0 2px rgba(59,130,246,0.25);
}