:root {
  --bg-primary: #f8fafc;
  --bg-surface: #ffffff;
  --text-color: #0f172a;
  --border-color: #e2e8f0;
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --danger-color: #ef4444;
  --danger-hover: #dc2626;
  --tab-active-bg: #ffffff;
  --tab-inactive-bg: #e2e8f0;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-surface: #1e293b;
  --text-color: #f8fafc;
  --border-color: #334155;
  --primary-color: #3b82f6;
  --primary-hover: #60a5fa;
  --danger-color: #f87171;
  --danger-hover: #ef4444;
  --tab-active-bg: #1e293b;
  --tab-inactive-bg: #334155;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-color);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.2s, color 0.2s;
}

.app-container {
  display: flex;
  flex-direction: column;
  height: 100vh;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
  padding: 12px;
  gap: 10px;
}

.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.logo-icon {
  width: 28px;
  height: 28px;
  color: var(--primary-color);
}

.app-title {
  font-size: 1.4rem;
  font-weight: 700;
}

/* Abas */
.tabs-bar {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  border-bottom: 2px solid var(--border-color);
}

.tab-item {
  padding: 8px 16px;
  background-color: var(--tab-inactive-bg);
  border: 1px solid var(--border-color);
  border-bottom: none;
  border-radius: 8px 8px 0 0;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  user-select: none;
  white-space: nowrap;
  transition: background-color 0.2s;
}

.tab-item.active {
  background-color: var(--tab-active-bg);
  border-color: var(--primary-color);
  color: var(--primary-color);
  font-weight: 600;
}

/* Toolbar */
.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.btn {
  padding: 8px 12px;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  background-color: var(--bg-surface);
  color: var(--text-color);
  font-size: 0.85rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: background-color 0.2s, border-color 0.2s;
}

.btn:hover {
  border-color: var(--primary-color);
}

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

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

/* Editor */
.editor-container {
  flex: 1;
  display: flex;
}

textarea {
  width: 100%;
  height: 100%;
  padding: 16px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background-color: var(--bg-surface);
  color: var(--text-color);
  font-size: 1rem;
  line-height: 1.5;
  resize: none;
  outline: none;
  box-shadow: var(--shadow);
  transition: border-color 0.2s;
}

textarea:focus {
  border-color: var(--primary-color);
}

/* Toast Notification */
.toast {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background-color: #0f172a;
  color: #ffffff;
  padding: 10px 18px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
  z-index: 1000;
  transition: opacity 0.3s;
}

.toast.hidden {
  opacity: 0;
  pointer-events: none;
}

.btn-undo {
  background: none;
  border: none;
  color: #60a5fa;
  font-weight: 700;
  cursor: pointer;
  text-decoration: underline;
}