/* === Reset & Base === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #0f1117;
  --card-bg: #1a1d2e;
  --border: #2a2d3e;
  --text: #e1e4ed;
  --text-muted: #8b8fa3;
  --accent: #4a9eff;
  --accent-hover: #3a7edf;
  --success: #4cd964;
  --danger: #ff3b30;
  --radius: 12px;
}

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

.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; width: 100%; }

/* === Header === */
.header {
  padding: 40px 0 30px;
  text-align: center;
  border-bottom: 1px solid var(--border);
}
.logo { font-size: 32px; font-weight: 700; color: #fff; }
.tagline { color: var(--text-muted); margin-top: 8px; font-size: 16px; }

/* === Tools Grid === */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
  padding: 30px 0;
}
.tool-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  cursor: pointer;
  transition: all 0.2s;
}
.tool-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(74, 158, 255, 0.1);
}
.tool-card .icon { font-size: 36px; margin-bottom: 12px; display: block; }
.tool-card h3 { font-size: 18px; margin-bottom: 6px; color: #fff; }
.tool-card p { font-size: 14px; color: var(--text-muted); line-height: 1.5; }

/* === Tool Panel === */
.tool-panel {
  padding: 30px 0;
}
.back-btn {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 8px 16px;
  border-radius: 8px;
  cursor: pointer;
  margin-bottom: 24px;
  font-size: 14px;
}
.back-btn:hover { border-color: var(--accent); color: var(--accent); }

.tool-view { background: var(--card-bg); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.tool-view h2 { font-size: 22px; color: #fff; margin-bottom: 20px; }

/* === Form Elements === */
textarea, input[type="text"], input[type="number"], select {
  width: 100%;
  padding: 12px;
  background: #0f1117;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-family: 'SF Mono', 'Monaco', 'Menlo', 'Courier New', monospace;
  font-size: 14px;
  resize: vertical;
}
textarea:focus, input:focus { outline: none; border-color: var(--accent); }

label { display: block; margin-bottom: 6px; font-size: 14px; color: var(--text-muted); }

.form-group { margin-bottom: 16px; }

.btn {
  padding: 10px 24px;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-success { background: var(--success); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-sm { padding: 6px 14px; font-size: 13px; }
.btn + .btn { margin-left: 8px; }

.output-area {
  margin-top: 16px;
  padding: 16px;
  background: #0f1117;
  border: 1px solid var(--border);
  border-radius: 8px;
  min-height: 60px;
  font-family: 'SF Mono', 'Monaco', 'Menlo', 'Courier New', monospace;
  font-size: 14px;
  white-space: pre-wrap;
  word-break: break-all;
  color: var(--success);
}
.output-area.error { color: var(--danger); }

.copy-btn {
  margin-top: 12px;
}

/* === JSON Tree View === */
.json-tree {
  background: #0f1117;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  font-family: 'SF Mono', 'Monaco', 'Menlo', 'Courier New', monospace;
  font-size: 14px;
  line-height: 1.7;
  overflow-x: auto;
  max-height: 500px;
  overflow-y: auto;
}
.json-entry { padding-left: 0; }
.json-root { padding-left: 0; }
.json-toggle {
  cursor: pointer;
  user-select: none;
  font-size: 10px;
  color: var(--text-muted);
  margin-right: 4px;
  display: inline-block;
  width: 14px;
  text-align: center;
  transition: color 0.15s;
}
.json-toggle:hover { color: var(--accent); }
.json-children { padding-left: 20px; border-left: 1px dashed rgba(255,255,255,0.08); margin-left: 6px; }
.json-entry.collapsed > .json-children { display: none; }
.clr-key { color: #d4bfff; }
.clr-string { color: #4cd964; }
.clr-number { color: #ff9500; }
.clr-boolean { color: #5ac8fa; }
.clr-null { color: #8e8e93; font-style: italic; }
.clr-punctuation { color: #8b8fa3; }
.clr-count { color: #555; font-size: 12px; font-style: italic; }

.row { display: flex; gap: 12px; }
.row > * { flex: 1; }

/* === Footer === */
.footer {
  margin-top: auto;
  text-align: center;
  padding: 24px 0;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 14px;
}

/* === Responsive === */
@media (max-width: 640px) {
  .tools-grid { grid-template-columns: 1fr; }
  .row { flex-direction: column; }
  .header { padding: 24px 0 20px; }
  .logo { font-size: 26px; }
}