/* ============================================
   Dapper Demo - Modern Dark Theme
   ============================================ */

:root {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-tertiary: #21262d;
  --border-color: #30363d;
  --text-primary: #f0f6fc;
  --text-secondary: #8b949e;
  --accent: #58a6ff;
  --accent-hover: #79b8ff;
  --success: #3fb950;
  --error: #f85149;
  --gradient-start: #7c3aed;
  --gradient-end: #2563eb;

  --font-sans: system-ui, sans-serif;
  --font-mono: ui-monospace, monospace;
}

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

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
}

/* Container */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 2rem;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

header h1 {
  font-size: 3rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 0.5rem;
}

.tagline {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 1rem;
}

.links {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
}

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

.links a:hover {
  color: var(--accent-hover);
}

/* Main */
main {
  flex: 1;
  display: flex;
  flex-direction: column;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.tab {
  padding: 0.75rem 1.5rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.tab:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.tab.active {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  border-color: transparent;
  color: white;
}

/* Options */
.options {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 1rem;
  padding: 1rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  flex-wrap: wrap;
}

.option-group {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.option-group label {
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
}

.option-group select,
.option-group input[type="number"] {
  padding: 0.5rem 0.75rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-primary);
  font-size: 0.9rem;
  font-family: inherit;
  min-width: 100px;
}

.option-group select:focus,
.option-group input[type="number"]:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.2);
}

/* Editor Container */
.editor-container {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 1rem;
  flex: 1;
  min-height: 400px;
}

.panel {
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  overflow: hidden;
}

.panel-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 1rem;
  background: var(--bg-tertiary);
  border-bottom: 1px solid var(--border-color);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.sample-buttons {
  display: flex;
  gap: 0.5rem;
}

.sample-btn {
  padding: 0.35rem 0.6rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  color: var(--text-secondary);
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

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

.copy-btn {
  padding: 0.35rem;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
}

.copy-btn:hover {
  background: var(--bg-secondary);
  color: var(--accent);
}

.copy-btn.copied {
  color: var(--success);
}

textarea {
  flex: 1;
  padding: 1rem;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.6;
  resize: none;
}

textarea:focus {
  outline: none;
}

textarea::placeholder {
  color: var(--text-secondary);
  opacity: 0.6;
}

#output {
  background: rgba(88, 166, 255, 0.03);
}

/* Divider */
.divider {
  display: flex;
  align-items: center;
  justify-content: center;
}

#formatBtn {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  border: none;
  border-radius: 50%;
  color: white;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(124, 58, 237, 0.4);
}

#formatBtn:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 20px rgba(124, 58, 237, 0.5);
}

#formatBtn:active {
  transform: scale(0.95);
}

/* Error */
.error {
  margin-top: 1rem;
  padding: 1rem;
  background: rgba(248, 81, 73, 0.1);
  border: 1px solid var(--error);
  border-radius: 8px;
  color: var(--error);
  font-size: 0.9rem;
}

.error.hidden {
  display: none;
}

/* Footer */
footer {
  margin-top: 2rem;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
}

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

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

/* Responsive */
@media (max-width: 900px) {
  .editor-container {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr auto 1fr;
  }

  .divider {
    padding: 0.5rem 0;
  }

  #formatBtn {
    transform: rotate(90deg);
  }

  #formatBtn:hover {
    transform: rotate(90deg) scale(1.1);
  }

  .options {
    flex-direction: column;
    gap: 1rem;
  }

  header h1 {
    font-size: 2rem;
  }

  .container {
    padding: 1rem;
  }

  .panel {
    min-height: 360px;
  }
}