/* ==================== VARIABLES ==================== */
:root {
  --primary: #39d353;
  --primary-dark: #2ea043;
  --primary-light: rgba(57, 211, 83, 0.1);
  --accent: #8b5cf6;
  --accent-light: rgba(139, 92, 246, 0.1);
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-card: #1c2128;
  --bg-input: #0d1117;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-muted: #6e7681;
  --border-color: #30363d;
  --border-light: rgba(255, 255, 255, 0.05);
  --danger: #ef4444;
  --warning: #f59e0b;
  --info: #3b82f6;
  --key-bg: #21262d;
  --key-border: #30363d;
  --key-text: #c9d1d9;
  --key-pressed: #39d353;
  --key-tested: rgba(57, 211, 83, 0.15);
  --key-tested-border: rgba(57, 211, 83, 0.4);
  --key-active-shadow: 0 0 20px rgba(57, 211, 83, 0.5);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.2);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --transition: 0.2s ease;
}

[data-theme="light"] {
  --bg-primary: #ffffff;
  --bg-secondary: #f6f8fa;
  --bg-card: #ffffff;
  --bg-input: #f6f8fa;
  --text-primary: #1f2328;
  --text-secondary: #656d76;
  --text-muted: #8b949e;
  --border-color: #d0d7de;
  --border-light: rgba(0, 0, 0, 0.04);
  --key-bg: #f0f2f5;
  --key-border: #d0d7de;
  --key-text: #1f2328;
  --key-tested: rgba(57, 211, 83, 0.1);
  --key-tested-border: rgba(57, 211, 83, 0.5);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.1);
}

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

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

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.text-gradient {
  background: linear-gradient(135deg, var(--primary), #00d2ff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ==================== HEADER ==================== */
.app-header {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  padding: var(--space-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
}

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

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
  color: var(--text-primary);
  font-size: 1.25rem;
  font-weight: 700;
}

.logo i { font-size: 1.5rem; color: var(--primary); }

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.icon-btn {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}

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

.back-btn {
  padding: 8px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition);
}

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

/* ==================== HERO ==================== */
.hero-section {
  text-align: center;
  padding: var(--space-xl) 0 var(--space-lg);
}

.hero-icon {
  width: 72px;
  height: 72px;
  border-radius: var(--radius-lg);
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-lg);
  animation: heroFloat 3s ease-in-out infinite;
}

@keyframes heroFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

.hero-icon i { font-size: 2rem; color: var(--primary); }

.hero-section h1 {
  font-size: 2.25rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-sm);
}

.hero-section p {
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
  font-size: 1rem;
}

/* ==================== TOOLBAR ==================== */
.toolbar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  flex-wrap: wrap;
  margin-bottom: var(--space-lg);
  padding: var(--space-md);
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

.toolbar-group {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.toolbar-group label {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-secondary);
  white-space: nowrap;
}

.toolbar-select {
  padding: 8px 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-input);
  color: var(--text-primary);
  font-size: 0.8125rem;
  outline: none;
  cursor: pointer;
  font-family: inherit;
}

.toolbar-select:focus { border-color: var(--primary); }

.toolbar-btn {
  padding: 8px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-input);
  color: var(--text-secondary);
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition);
  font-family: inherit;
}

.toolbar-btn:hover { border-color: var(--primary); color: var(--primary); }
.toolbar-btn.active { border-color: var(--primary); color: var(--primary); background: var(--primary-light); }
.toolbar-btn.danger:hover { border-color: var(--danger); color: var(--danger); }

.toolbar-divider {
  width: 1px;
  height: 24px;
  background: var(--border-color);
}

/* ==================== STATS BAR ==================== */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-md) var(--space-lg);
  text-align: center;
  transition: all var(--transition);
}

.stat-card:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
}

.stat-value {
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.stat-value.green { color: var(--primary); }
.stat-value.blue { color: var(--info); }
.stat-value.purple { color: var(--accent); }
.stat-value.orange { color: var(--warning); }
.stat-value.red { color: var(--danger); }

.stat-label {
  font-size: 0.75rem;
  color: var(--text-secondary);
  font-weight: 500;
  margin-top: 2px;
}

/* ==================== KEYBOARD CONTAINER ==================== */
.keyboard-wrapper {
  display: flex;
  justify-content: center;
  margin-bottom: var(--space-xl);
  overflow-x: auto;
  padding: var(--space-sm) 0;
}

.keyboard {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: var(--space-lg);
  box-shadow: var(--shadow-lg);
  display: inline-block;
  min-width: fit-content;
  position: relative;
}

.keyboard-inner {
  display: flex;
  gap: 20px;
}

.keyboard-main {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.keyboard-nav {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.keyboard-numpad {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-left: 8px;
}

.key-row {
  display: flex;
  gap: 4px;
  align-items: stretch;
}

/* ==================== KEY STYLES ==================== */
.key {
  min-width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--key-border);
  background: var(--key-bg);
  color: var(--key-text);
  font-size: 0.7rem;
  font-weight: 600;
  font-family: 'Inter', sans-serif;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  transition: all 0.1s ease;
  position: relative;
  user-select: none;
  padding: 2px 6px;
  line-height: 1.1;
  flex-shrink: 0;
}

.key:hover {
  border-color: var(--text-muted);
  background: var(--bg-secondary);
}

.key.tested {
  background: var(--key-tested);
  border-color: var(--key-tested-border);
  color: var(--primary);
}

.key.active {
  background: var(--primary) !important;
  border-color: var(--primary) !important;
  color: #fff !important;
  transform: scale(0.95);
  box-shadow: var(--key-active-shadow);
}

.key .key-label {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1px;
  pointer-events: none;
}

.key .key-sub {
  font-size: 0.55rem;
  opacity: 0.5;
}

.key .key-icon {
  font-size: 0.85rem;
  pointer-events: none;
}

/* Key size variations */
.key-w125 { min-width: 56px; }
.key-w150 { min-width: 68px; }
.key-w175 { min-width: 79px; }
.key-w200 { min-width: 92px; }
.key-w225 { min-width: 103px; }
.key-w250 { min-width: 115px; }
.key-w275 { min-width: 126px; }
.key-w625 { min-width: 290px; }
.key-h200 { height: 92px; }

/* Function key row spacing */
.key-fn { min-width: 40px; height: 36px; font-size: 0.65rem; }
.key-gap { width: 20px; flex-shrink: 0; }
.key-gap-half { width: 10px; flex-shrink: 0; }

/* Special key styles */
.key-enter { background: rgba(57, 211, 83, 0.06); border-color: rgba(57, 211, 83, 0.2); }
.key-enter.tested { background: var(--key-tested); }
.key-space { min-width: 290px; }

/* ==================== LAST KEY DISPLAY ==================== */
.last-key-display {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  margin-bottom: var(--space-lg);
  display: flex;
  align-items: center;
  gap: var(--space-xl);
}

.last-key-visual {
  width: 100px;
  height: 100px;
  border-radius: var(--radius-lg);
  background: var(--primary-light);
  border: 2px solid var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary);
  transition: all 0.15s ease;
}

.last-key-visual.pulse {
  animation: keyPulse 0.3s ease;
}

@keyframes keyPulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.1); box-shadow: 0 0 30px rgba(57, 211, 83, 0.4); }
  100% { transform: scale(1); }
}

.last-key-info {
  flex: 1;
}

.last-key-info h3 {
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 600;
  margin-bottom: var(--space-xs);
}

.last-key-name {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: var(--space-sm);
}

.last-key-details {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.key-detail-badge {
  padding: 4px 10px;
  border-radius: 20px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 4px;
}

.key-detail-badge strong {
  color: var(--text-primary);
}

/* ==================== KEY HISTORY ==================== */
.history-section {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-xl);
  overflow: hidden;
}

.history-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--border-color);
}

.history-header h3 {
  font-size: 0.9375rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.history-body {
  padding: var(--space-md) var(--space-lg);
  max-height: 140px;
  overflow-y: auto;
}

.history-keys {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.history-key {
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-primary);
  animation: historyIn 0.2s ease;
}

@keyframes historyIn {
  from { opacity: 0; transform: scale(0.8); }
  to { opacity: 1; transform: scale(1); }
}

.history-empty {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.8125rem;
  padding: var(--space-md) 0;
}

/* ==================== PROGRESS BAR ==================== */
.progress-section {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  margin-bottom: var(--space-lg);
}

.progress-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-md);
}

.progress-header h3 {
  font-size: 0.9375rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.progress-header span {
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--primary);
}

.progress-bar-track {
  height: 12px;
  background: var(--bg-secondary);
  border-radius: 6px;
  overflow: hidden;
  border: 1px solid var(--border-color);
}

.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), #00d2ff);
  border-radius: 6px;
  width: 0%;
  transition: width 0.4s ease;
  position: relative;
}

.progress-bar-fill::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  animation: progressShine 2s infinite;
}

@keyframes progressShine {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

/* ==================== FEATURES SECTION ==================== */
.features-section {
  padding: var(--space-xl) 0 60px;
  text-align: center;
}

.features-section h2 {
  font-size: 1.75rem;
  font-weight: 800;
  margin-bottom: var(--space-xl);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
  text-align: left;
}

.feature-card {
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  transition: all var(--transition);
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--primary);
  box-shadow: 0 8px 30px rgba(57, 211, 83, 0.08);
}

.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-md);
}

.feature-icon i { font-size: 1.25rem; color: var(--primary); }
.feature-card h3 { font-size: 1rem; margin-bottom: var(--space-xs); }
.feature-card p { font-size: 0.8125rem; color: var(--text-secondary); line-height: 1.5; }

/* ==================== FOOTER ==================== */
.app-footer {
  padding: var(--space-lg) 0;
  text-align: center;
  border-top: 1px solid var(--border-color);
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

/* ==================== HEATMAP INDICATOR ==================== */
.key.heat-1 { background: rgba(57, 211, 83, 0.1); }
.key.heat-2 { background: rgba(57, 211, 83, 0.2); }
.key.heat-3 { background: rgba(57, 211, 83, 0.3); }
.key.heat-4 { background: rgba(57, 211, 83, 0.45); }
.key.heat-5 { background: rgba(57, 211, 83, 0.6); color: #fff; }

/* ==================== COMPLETION ANIMATION ==================== */
.keyboard.complete {
  animation: completeGlow 1s ease;
}

@keyframes completeGlow {
  0%, 100% { box-shadow: var(--shadow-lg); }
  50% { box-shadow: 0 0 60px rgba(57, 211, 83, 0.3), 0 0 120px rgba(57, 211, 83, 0.1); }
}

/* ==================== TOAST ==================== */
.toast {
  position: fixed;
  top: 80px;
  right: 20px;
  padding: 12px 20px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--primary);
  color: var(--text-primary);
  font-size: 0.875rem;
  font-weight: 600;
  z-index: 999;
  display: flex;
  align-items: center;
  gap: 8px;
  box-shadow: var(--shadow-lg);
  animation: toastIn 0.3s ease, toastOut 0.3s ease 2.7s forwards;
}

@keyframes toastIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

@keyframes toastOut {
  from { transform: translateX(0); opacity: 1; }
  to { transform: translateX(100%); opacity: 0; }
}

/* ==================== RESPONSIVE ==================== */
@media (max-width: 1200px) {
  .keyboard {
    padding: var(--space-md);
  }
  .key {
    min-width: 38px;
    height: 38px;
    font-size: 0.6rem;
  }
  .key-fn { min-width: 34px; height: 32px; }
  .key-w125 { min-width: 48px; }
  .key-w150 { min-width: 58px; }
  .key-w175 { min-width: 68px; }
  .key-w200 { min-width: 78px; }
  .key-w225 { min-width: 88px; }
  .key-w250 { min-width: 98px; }
  .key-w275 { min-width: 108px; }
  .key-w625 { min-width: 250px; }
  .key-h200 { height: 78px; }
}

@media (max-width: 900px) {
  .stats-bar {
    grid-template-columns: repeat(3, 1fr);
  }
  .last-key-display {
    flex-direction: column;
    text-align: center;
  }
  .features-grid { grid-template-columns: 1fr; }
  .toolbar { gap: var(--space-sm); }
}

@media (max-width: 768px) {
  .hero-section h1 { font-size: 1.75rem; }
  .stats-bar { grid-template-columns: repeat(2, 1fr); }
  .keyboard {
    padding: var(--space-sm);
    border-radius: var(--radius-md);
  }
  .key {
    min-width: 30px;
    height: 32px;
    font-size: 0.5rem;
    border-radius: 4px;
    gap: 2px;
    padding: 1px 3px;
  }
  .key-fn { min-width: 28px; height: 26px; font-size: 0.45rem; }
  .key-gap { width: 10px; }
  .key-w125 { min-width: 38px; }
  .key-w150 { min-width: 46px; }
  .key-w175 { min-width: 54px; }
  .key-w200 { min-width: 62px; }
  .key-w225 { min-width: 70px; }
  .key-w250 { min-width: 78px; }
  .key-w275 { min-width: 86px; }
  .key-w625 { min-width: 190px; }
  .key-h200 { height: 66px; }
  .keyboard-inner { gap: 10px; }
}

@media (max-width: 480px) {
  .container { padding: 0 var(--space-md); }
  .stats-bar { grid-template-columns: 1fr 1fr; }
  .stat-card { padding: var(--space-sm) var(--space-md); }
  .stat-value { font-size: 1.25rem; }
}

/* ==================== SCROLLBAR ==================== */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }