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

:root {
  --primary: #06b6d4;
  --primary-hover: #0891b2;
  --bg: #0f0f0f;
  --bg-secondary: #1a1a1a;
  --bg-tertiary: #252525;
  --surface: #1a1a1a;
  --text: #ffffff;
  --text-secondary: #a1a1a1;
  --border: #333;
  --radius: 8px;
  --radius-lg: 12px;
}

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

.container {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
header {
  padding: 30px 0 25px;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

/* Site Nav */
.site-nav {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  margin-bottom: 15px;
}

.site-nav .logo {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 4px;
  background: var(--bg-tertiary);
  padding: 4px;
  border-radius: 8px;
}

.nav-link {
  padding: 8px 16px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: 6px;
  transition: all 0.2s;
}

.nav-link:hover {
  color: var(--text);
}

.nav-link.active {
  background: var(--primary);
  color: white;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 8px;
  margin: 30px 0 20px;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0;
}

.tab {
  background: none;
  border: none;
  color: var(--text-secondary);
  padding: 12px 20px;
  font-size: 1rem;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  transition: all 0.2s;
}

.tab:hover {
  color: var(--text);
}

.tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

/* Tab Content */
.tab-content {
  display: none;
  padding: 20px 0;
}

.tab-content.active {
  display: block;
}

/* Upload Area */
.upload-area {
  border: 2px dashed var(--border);
  border-radius: var(--radius-lg);
  padding: 50px 20px;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
  background: var(--bg-secondary);
}

.upload-area:hover,
.upload-area.dragover {
  border-color: var(--primary);
  background: var(--bg-tertiary);
}

.upload-prompt {
  pointer-events: none;
}

.upload-icon {
  font-size: 3rem;
  display: block;
  margin-bottom: 15px;
}

.upload-area p {
  margin: 5px 0;
}

.upload-area .small {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.upload-area .hint {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 15px;
}

.preview-image {
  max-width: 200px;
  max-height: 200px;
  border-radius: var(--radius);
}

/* Forms */
.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--text-secondary);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

input[type="text"],
select {
  width: 100%;
  padding: 12px 15px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 1rem;
}

input[type="text"]:focus,
select:focus {
  outline: none;
  border-color: var(--primary);
}

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

.color-input input[type="color"] {
  width: 50px;
  height: 44px;
  padding: 2px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  background: var(--bg-tertiary);
}

.color-input input[type="text"] {
  flex: 1;
  font-family: monospace;
}

/* Emoji Grid */
.emoji-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(50px, 1fr));
  gap: 8px;
  max-height: 200px;
  overflow-y: auto;
  padding: 10px;
  background: var(--bg-tertiary);
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.emoji-btn {
  width: 45px;
  height: 45px;
  font-size: 1.5rem;
  background: var(--bg-secondary);
  border: 2px solid transparent;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.2s;
}

.emoji-btn:hover {
  background: var(--bg);
  transform: scale(1.1);
}

.emoji-btn.selected {
  border-color: var(--primary);
  background: var(--bg);
}

/* Preview Section */
.preview-section {
  margin: 30px 0;
  padding: 25px;
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
}

.preview-section h2 {
  font-size: 1.1rem;
  margin-bottom: 20px;
  color: var(--text-secondary);
}

.preview-container {
  display: flex;
  align-items: center;
  gap: 30px;
  flex-wrap: wrap;
}

.preview-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.preview-item canvas {
  background: #fff;
  border-radius: 4px;
}

.preview-item span {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.preview-browser {
  flex: 1;
  min-width: 200px;
}

.browser-tab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 15px;
  background: var(--bg-tertiary);
  border-radius: 8px 8px 0 0;
  border: 1px solid var(--border);
  border-bottom: none;
}

.browser-tab canvas {
  border-radius: 2px;
}

.browser-tab span {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* Download Section */
.download-section {
  text-align: center;
  margin: 30px 0;
}

.btn-primary {
  background: var(--primary);
  color: white;
  border: none;
  padding: 15px 40px;
  font-size: 1.1rem;
  font-weight: 600;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.2s;
}

.btn-primary:hover:not(:disabled) {
  background: var(--primary-hover);
  transform: translateY(-1px);
}

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

.download-info {
  margin-top: 12px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* Output Info */
.output-info {
  margin: 40px 0;
  padding: 25px;
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
}

.output-info h2 {
  font-size: 1.1rem;
  margin-bottom: 20px;
  color: var(--text-secondary);
}

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

.output-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 12px;
  background: var(--bg-tertiary);
  border-radius: var(--radius);
}

.output-item code {
  font-family: monospace;
  font-size: 0.9rem;
  color: var(--primary);
}

.output-item span {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

/* Footer */
footer {
  margin-top: 60px;
  padding: 30px 0;
  text-align: center;
  border-top: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 600px) {
  header h1 {
    font-size: 1.8rem;
  }

  .tabs {
    flex-wrap: wrap;
  }

  .tab {
    flex: 1;
    text-align: center;
    padding: 10px 15px;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .preview-container {
    justify-content: center;
  }

  .preview-browser {
    width: 100%;
    text-align: center;
  }
}