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

:root {
  --bg: #0d0d0d;
  --surface: #1a1a1a;
  --surface-2: #242424;
  --border: #333;
  --text: #e5e5e5;
  --text-muted: #888;
  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --danger: #ef4444;
  --success: #22c55e;
  --radius: 8px;
}

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

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

.login-page {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: radial-gradient(ellipse at top, #1a1a2e, #0d0d0d);
}

.login-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 48px 40px;
  width: 100%;
  max-width: 400px;
  text-align: center;
}

.login-card h1 {
  font-size: 1.5rem;
  margin-bottom: 4px;
}

.login-card p {
  color: var(--text-muted);
  margin-bottom: 32px;
  font-size: 0.9rem;
}

.login-card .logo {
  width: 48px;
  height: 48px;
  background: var(--accent);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  font-size: 1.4rem;
}

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

.form-group label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text-muted);
}

input, textarea, select {
  width: 100%;
  padding: 10px 14px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.95rem;
  font-family: inherit;
  outline: none;
  transition: border-color 0.2s;
}

input:focus, textarea:focus, select:focus {
  border-color: var(--accent);
}

textarea {
  resize: vertical;
  min-height: 120px;
}

select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23888' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

select option {
  background: var(--surface);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  border: none;
  border-radius: var(--radius);
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, opacity 0.2s;
}

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

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

.btn-primary:hover:not(:disabled) {
  background: var(--accent-hover);
}

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
}

.btn-ghost:hover {
  background: var(--surface-2);
  color: var(--text);
}

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

.btn-danger:hover {
  background: #dc2626;
}

.btn-block {
  width: 100%;
}

.btn-row {
  display: flex;
  gap: 8px;
  align-items: center;
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.app-header h1 {
  font-size: 1.15rem;
  display: flex;
  align-items: center;
  gap: 10px;
}

.app-header .logo-small {
  width: 32px;
  height: 32px;
  background: var(--accent);
  border-radius: 8px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
}

.app-main {
  max-width: 960px;
  margin: 0 auto;
  padding: 32px 24px;
}

.input-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 24px;
}

.input-section .full-width {
  grid-column: 1 / -1;
}

.section-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 24px;
}

.section-card h2 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  display: flex;
  align-items: center;
  gap: 10px;
}

.tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  margin-bottom: 16px;
}

.tab {
  padding: 10px 20px;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.9rem;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}

.tab:hover { color: var(--text); }
.tab.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.tab-content { display: none; }
.tab-content.active { display: block; }

.preview-frame {
  width: 100%;
  min-height: 500px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
}

.code-block {
  background: #111;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  overflow-x: auto;
  position: relative;
}

.code-block pre {
  font-family: 'Fira Code', 'Cascadia Code', 'JetBrains Mono', monospace;
  font-size: 0.85rem;
  line-height: 1.5;
  white-space: pre-wrap;
  word-break: break-all;
  color: #e5e5e5;
}

.copy-btn {
  position: absolute;
  top: 12px;
  right: 12px;
  padding: 6px 14px;
  font-size: 0.8rem;
  border-radius: 4px;
}

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

/* Thinking box */
.thinking-box {
  background: #111;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  max-height: 300px;
  overflow-y: auto;
  font-family: 'Fira Code', 'Cascadia Code', 'JetBrains Mono', monospace;
  font-size: 0.8rem;
  line-height: 1.5;
  color: #94a3b8;
  white-space: pre-wrap;
  word-break: break-word;
}

.thinking-box::-webkit-scrollbar {
  width: 6px;
}

.thinking-box::-webkit-scrollbar-track {
  background: transparent;
}

.thinking-box::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

/* Notes box */
.notes-box {
  background: var(--surface-2);
  border: 1px solid #8aa19d;
  border-radius: var(--radius);
  padding: 14px 16px;
  font-size: 0.85rem;
  line-height: 1.6;
  color: var(--text-muted);
  white-space: pre-wrap;
}

/* Spinner */
.spinner {
  display: inline-block;
  width: 14px;
  height: 14px;
  border: 2px solid rgba(255,255,255,0.2);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.error-msg {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid var(--danger);
  color: var(--danger);
  padding: 12px 16px;
  border-radius: var(--radius);
  margin-bottom: 16px;
  font-size: 0.9rem;
  display: none;
}

.error-msg.show { display: block; }

.success-msg {
  background: rgba(34, 197, 94, 0.1);
  border: 1px solid var(--success);
  color: var(--success);
  padding: 12px 16px;
  border-radius: var(--radius);
  margin-bottom: 16px;
  font-size: 0.9rem;
  display: none;
}

.success-msg.show { display: block; }

.result-placeholder {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-muted);
}

.result-placeholder svg {
  width: 48px;
  height: 48px;
  margin-bottom: 16px;
  opacity: 0.4;
}

.result-placeholder p {
  font-size: 0.95rem;
}

@media (max-width: 640px) {
  .input-section {
    grid-template-columns: 1fr;
  }
  .app-main {
    padding: 16px;
  }
  .login-card {
    padding: 32px 24px;
    margin: 16px;
  }
}