/* ========================================
   CSS 变量定义
   ======================================== */
:root {
  --paper: #efe9dd;
  --paper-2: #e5ddcb;
  --paper-3: #d9d0bb;
  --ink: #171310;
  --ink-soft: #4a4239;
  --red: #ff2e12;
  --red-deep: #d6240c;

  --color-bg: var(--paper);
  --color-bg-secondary: var(--paper-2);
  --color-bg-card: var(--paper-3);
  --color-text: var(--ink);
  --color-text-secondary: var(--ink-soft);
  --color-text-muted: #8a7f6f;
  --color-primary: var(--red);
  --color-primary-hover: var(--red-deep);
  --color-correct: #2e7d32;
  --color-correct-bg: rgba(46, 125, 50, 0.15);
  --color-error: var(--red);
  --color-error-bg: rgba(255, 46, 18, 0.12);
  --color-border: var(--ink);
  --color-key-bg: var(--paper-3);
  --color-key-border: var(--ink);
  --color-key-text: var(--ink);
  --color-key-shift: var(--ink-soft);
  --color-key-hover: var(--paper-2);

  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-xxl: 48px;

  --font-display: "Anton", "Noto Sans SC", sans-serif;
  --font-cjk: "Noto Sans SC", sans-serif;
  --font-family: "Hanken Grotesk", "Noto Sans SC", "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-family-mono: "Cascadia Code", "Fira Code", "Consolas", "Monaco", monospace;

  --radius-sm: 0px;
  --radius-md: 0px;
  --radius-lg: 0px;

  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;

  --rule: 2px solid var(--ink);
}

[data-theme="dark"] {
  --paper: #1a1816;
  --paper-2: #242120;
  --paper-3: #2e2b28;
  --ink: #e8e2d8;
  --ink-soft: #9a938a;
  --red: #ff4d3a;
  --red-deep: #ff6b5a;

  --color-text-muted: #7a746c;
  --color-correct: #4caf50;
  --color-correct-bg: rgba(76, 175, 80, 0.18);
  --color-error-bg: rgba(255, 77, 58, 0.15);
}

[data-theme="dark"] .grain {
  opacity: 0.03;
}

[data-theme="dark"] .kb-keyboard {
  background-color: var(--ink);
  border-color: var(--ink-soft);
}

[data-theme="dark"] .kb-key {
  background-color: var(--paper-3);
  border-color: var(--ink-soft);
  color: var(--ink);
  box-shadow: 0 3px 0 var(--ink-soft);
}

[data-theme="dark"] .kb-key:hover {
  background-color: var(--paper-2);
  box-shadow: 0 4px 0 var(--ink-soft);
}

[data-theme="dark"] .kb-key:active {
  box-shadow: 0 0 0 var(--ink-soft);
}

[data-theme="dark"] .kb-key-shift-label {
  color: var(--ink-soft);
}

[data-theme="dark"] #result-container {
  background-color: rgba(10, 9, 8, 0.9);
}

[data-theme="dark"] .result-card {
  background-color: var(--paper);
  border-color: var(--ink-soft);
}

[data-theme="dark"] .result-stat-item {
  background-color: var(--paper-2);
  border-color: var(--ink-soft);
}

[data-theme="dark"] ::-webkit-scrollbar-track {
  background-color: var(--paper);
}

[data-theme="dark"] ::-webkit-scrollbar-thumb {
  background-color: var(--paper-3);
}

[data-theme="dark"] ::-webkit-scrollbar-thumb:hover {
  background-color: var(--ink-soft);
}

/* ========================================
   全局重置
   ======================================== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  background-color: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 80;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.55'/%3E%3C/svg%3E");
  opacity: .07;
  mix-blend-mode: multiply;
}

/* ========================================
   页面整体布局
   ======================================== */
.app-container {
  max-width: 960px;
  margin: 0 auto;
  padding: clamp(16px, 3vw, 48px);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
}

.app-container::before,
.app-container::after {
  content: "";
  position: fixed;
  width: 14px;
  height: 14px;
  border-color: var(--ink);
  border-style: solid;
  border-width: 0;
  opacity: 0.2;
  pointer-events: none;
  z-index: 81;
}
.app-container::before {
  top: 12px;
  left: 12px;
  border-top-width: 2px;
  border-left-width: 2px;
}
.app-container::after {
  bottom: 12px;
  right: 12px;
  border-bottom-width: 2px;
  border-right-width: 2px;
}

.app-header {
  margin-top: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) 0;
  border-bottom: var(--rule);
  margin-bottom: var(--spacing-lg);
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.app-title {
  font-family: var(--font-display);
  font-size: clamp(1.2rem, 2.5vw, 1.5rem);
  font-weight: 400;
  color: var(--ink);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  line-height: 0.9;
}

.app-title b {
  color: var(--red);
}

.app-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

/* ========================================
   工具栏样式（tb- 前缀）
   ======================================== */
.tb-toolbar {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.tb-layout-group {
  display: flex;
  gap: 2px;
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-md);
  padding: 2px;
  border: var(--rule);
}

.tb-layout-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  border: none;
  border-radius: var(--radius-sm);
  background-color: transparent;
  color: var(--color-text-secondary);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-family);
  white-space: nowrap;
}

.tb-layout-btn:hover {
  background-color: var(--color-key-hover);
  color: var(--color-text);
}

.tb-layout-btn-active {
  background-color: var(--red) !important;
  color: #fff !important;
  font-weight: 600;
}

.tb-immersive-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  font-family: var(--font-family);
  font-weight: 800;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.tb-immersive-btn:hover {
  background-color: var(--color-key-hover);
  color: var(--color-text);
  border-color: var(--red);
}

.tb-immersive-active {
  background-color: var(--red) !important;
  color: #fff !important;
  border-color: var(--red) !important;
  font-weight: 600;
}

.tb-clear-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-muted);
  font-family: var(--font-family);
  font-weight: 800;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.tb-clear-btn:hover {
  background-color: var(--color-error-bg);
  color: var(--red);
  border-color: var(--red);
}

.tb-theme-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  font-family: var(--font-family);
  font-weight: 800;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.tb-theme-btn:hover {
  background-color: var(--color-key-hover);
  color: var(--color-text);
  border-color: var(--red);
}

.tb-import-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  font-family: var(--font-family);
  font-weight: 800;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.tb-import-btn:hover {
  background-color: var(--color-key-hover);
  color: var(--color-text);
  border-color: var(--red);
}

/* ========================================
   练习文本样式（pt- 前缀）
   ======================================== */
#practice-container {
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  border: var(--rule);
  position: relative;
}

#practice-container::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--red);
  opacity: 0.6;
}

.pt-text {
  font-family: var(--font-family-mono);
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  line-height: 2.2;
  letter-spacing: 2px;
  word-break: break-all;
}

.pt-char {
  display: inline-block;
  padding: 2px 1px;
  border-bottom: 2px solid transparent;
  transition: all var(--transition-fast);
}

.pt-char-space {
  width: 0.6em;
}

.pt-char-current {
  border-bottom-color: var(--red);
  background-color: rgba(255, 46, 18, 0.12);
  animation: pt-cursor-blink 1s ease-in-out infinite;
}

.pt-char-completed {
  color: var(--color-correct);
  font-weight: 600;
  border-bottom-color: transparent;
  background-color: transparent;
  animation: none;
}

.pt-char-error {
  color: var(--red);
  text-decoration: underline;
  text-decoration-style: wavy;
  text-underline-offset: 3px;
  border-bottom-color: transparent;
  background-color: rgba(255, 46, 18, 0.08);
  animation: none;
}

@keyframes pt-cursor-blink {
  0%, 100% {
    border-bottom-color: var(--red);
    background-color: rgba(255, 46, 18, 0.12);
  }
  50% {
    border-bottom-color: transparent;
    background-color: rgba(255, 46, 18, 0.04);
  }
}

/* ========================================
   统计信息样式
   ======================================== */
#stats-container {
  display: flex;
  gap: var(--spacing-lg);
  justify-content: center;
  flex-wrap: wrap;
  padding: var(--spacing-sm) 0;
}

.stats-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.stats-label {
  font-size: 0.7rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-weight: 800;
}

.stats-value {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--color-text);
}

.stats-correct {
  color: var(--color-correct);
}

.stats-error {
  color: var(--red);
}

/* ========================================
   英语模式样式（en- 前缀）
   ======================================== */
#english-practice-container,
#english-list-container {
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  border: var(--rule);
  position: relative;
}

#english-practice-container::before,
#english-list-container::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--red);
  opacity: 0.6;
}

#english-stats-container {
  display: flex;
  gap: var(--spacing-lg);
  justify-content: center;
  flex-wrap: wrap;
  padding: var(--spacing-sm) 0;
}

.en-panel-label {
  margin: 0 0 var(--spacing-xs);
  font-size: 0.72rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-weight: 800;
}

.en-current-zh {
  margin: 0 0 var(--spacing-md);
  font-family: var(--font-cjk);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 700;
  color: var(--color-text);
}

.en-current-en {
  display: flex;
  gap: 0.35rem;
  flex-wrap: wrap;
  margin-bottom: var(--spacing-sm);
  font-family: var(--font-family-mono);
  font-size: clamp(1rem, 2vw, 1.2rem);
  letter-spacing: 0.08em;
}

.en-letter {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 1.5em;
  padding: 0.2rem 0.1rem;
  border-bottom: 2px solid var(--color-border);
  color: var(--color-text-muted);
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

.en-letter-current {
  border-bottom-color: var(--red);
  color: var(--color-text);
  background-color: var(--color-error-bg);
  animation: pt-cursor-blink 1s ease-in-out infinite;
}

.en-letter-correct {
  color: var(--color-correct);
  border-bottom-color: transparent;
}

.en-letter-error {
  color: var(--red);
  text-decoration: underline;
  text-decoration-style: wavy;
  text-underline-offset: 3px;
  border-bottom-color: transparent;
  background-color: rgba(255, 46, 18, 0.08);
}

.en-letter-flash {
  animation: en-letter-flash 260ms ease-out 1;
}

.en-letter-pending {
  color: var(--color-text-muted);
}

@keyframes en-letter-flash {
  0% {
    transform: translateY(0) scale(1);
    background-color: rgba(255, 46, 18, 0.08);
    box-shadow: 0 0 0 rgba(255, 46, 18, 0);
  }
  35% {
    transform: translateY(-1px) scale(1.08);
    background-color: rgba(255, 46, 18, 0.22);
    box-shadow: 0 0 0 4px rgba(255, 46, 18, 0.12);
  }
  100% {
    transform: translateY(0) scale(1);
    background-color: rgba(255, 46, 18, 0.08);
    box-shadow: 0 0 0 rgba(255, 46, 18, 0);
  }
}

.en-hint,
.en-current-hint {
  margin: 0;
  color: var(--color-text-secondary);
  font-size: 0.95rem;
}

.en-word-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--spacing-sm);
}

.en-word-item {
  border: var(--rule);
  background-color: var(--color-bg);
  padding: var(--spacing-md);
  transition: background-color var(--transition-fast), border-color var(--transition-fast);
}

.en-word-item-current {
  border-color: var(--red);
  background-color: var(--color-error-bg);
}

.en-word-item-completed {
  border-color: var(--color-correct);
  background-color: var(--color-correct-bg);
}

.en-word-item-zh {
  margin: 0 0 0.35rem;
  font-weight: 700;
  color: var(--color-text);
}

.en-word-item-en {
  margin: 0;
  font-family: var(--font-family-mono);
  color: var(--color-text-secondary);
  letter-spacing: 0.06em;
}

/* ========================================
   虚拟键盘样式（kb- 前缀）
   ======================================== */
#keyboard-container {
  padding: var(--spacing-md) 0;
}

.kb-keyboard {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-md);
  background-color: var(--ink);
  border-radius: var(--radius-lg);
  border: var(--rule);
}

.kb-row {
  display: flex;
  justify-content: center;
  gap: var(--spacing-xs);
}

.kb-key {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background-color: var(--paper-3);
  border: 1px solid var(--ink);
  border-radius: var(--radius-sm);
  color: var(--ink);
  font-family: var(--font-family);
  font-size: 0.85rem;
  cursor: default;
  transition: all var(--transition-fast);
  position: relative;
  user-select: none;
  box-shadow: 0 3px 0 var(--ink);
}

.kb-key:hover {
  background-color: var(--paper-2);
  transform: translateY(-1px);
  box-shadow: 0 4px 0 var(--ink);
}

.kb-key:active {
  box-shadow: 0 0 0 var(--ink);
  transform: translateY(3px);
}

.kb-key-label {
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 400;
  line-height: 1;
  letter-spacing: 0.02em;
}

.kb-key-shift-label {
  font-size: 0.6rem;
  color: var(--ink-soft);
  line-height: 1;
  margin-top: 1px;
}

/* 宽按键 */
.kb-key-wide {
  width: auto;
  min-width: 72px;
  padding: 0 var(--spacing-sm);
}

/* 空格键 */
.kb-key-space {
  width: 260px;
  min-width: 200px;
}

/* 正确按键高亮 */
.kb-key-correct {
  background-color: var(--color-correct) !important;
  border-color: var(--color-correct) !important;
  color: #fff !important;
  box-shadow: 0 0 12px rgba(46, 125, 50, 0.4);
  transform: translateY(0);
}

.kb-key-correct .kb-key-shift-label {
  color: rgba(255, 255, 255, 0.7) !important;
}

.kb-key-error {
  background-color: var(--red) !important;
  border-color: var(--red) !important;
  color: #fff !important;
  box-shadow: 0 0 12px rgba(255, 46, 18, 0.4);
  transform: translateY(0);
}

.kb-key-error .kb-key-shift-label {
  color: rgba(255, 255, 255, 0.7) !important;
}

.kb-key-hint {
  background-color: #ffab00 !important;
  border-color: #ff8f00 !important;
  color: #fff !important;
  box-shadow: 0 0 16px rgba(255, 171, 0, 0.5);
  transform: translateY(0);
  animation: kb-hint-pulse 0.6s ease-in-out infinite alternate;
}

.kb-key-hint .kb-key-shift-label {
  color: rgba(255, 255, 255, 0.7) !important;
}

@keyframes kb-hint-pulse {
  from {
    box-shadow: 0 0 8px rgba(255, 171, 0, 0.3);
  }
  to {
    box-shadow: 0 0 20px rgba(255, 171, 0, 0.7);
  }
}

.kb-key-finger-0 { border-left: 3px solid var(--red); }
.kb-key-finger-1 { border-left: 3px solid #e67e22; }
.kb-key-finger-2 { border-left: 3px solid #f1c40f; }
.kb-key-finger-3 { border-left: 3px solid #2ecc71; }
.kb-key-finger-4 { border-left: 3px solid #3498db; }

.kb-key-home {
  border-bottom: 3px solid var(--red);
}

/* ========================================
   练习结果样式
   ======================================== */
#result-container {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(23, 19, 16, 0.85);
  z-index: 1000;

  align-items: center;
  justify-content: center;
}

#result-container[style*="display: block"] {
  display: flex !important;
}

.result-card {
  background-color: var(--paper);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xxl);
  max-width: 420px;
  width: 90%;
  text-align: center;
  border: var(--rule);
  box-shadow: 0 20px 60px rgba(23, 19, 16, 0.4);
}

.result-title {
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 400;
  color: var(--red);
  margin-bottom: var(--spacing-lg);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.result-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
}

.result-stat-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: var(--spacing-sm);
  background-color: var(--paper-2);
  border-radius: var(--radius-md);
  border: 1px solid var(--ink);
}

.result-stat-label {
  font-size: 0.7rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-weight: 800;
}

.result-stat-value {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--color-text);
}

.result-correct {
  color: var(--color-correct);
}

.result-error {
  color: var(--red);
}

.result-actions {
  display: flex;
  gap: var(--spacing-sm);
  justify-content: center;
  flex-wrap: wrap;
}

.result-restart-btn {
  padding: var(--spacing-sm) var(--spacing-xl);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--red);
  color: #fff;
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.result-close-btn {
  padding: var(--spacing-sm) var(--spacing-xl);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--paper-2);
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.result-restart-btn:hover,
.result-close-btn:hover {
  background-color: var(--red-deep);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(255, 46, 18, 0.3);
}

/* ========================================
   导入词库弹窗样式
   ======================================== */
#import-container {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(23, 19, 16, 0.85);
  z-index: 1000;
  align-items: center;
  justify-content: center;
}

#import-container[style*="display: flex"] {
  display: flex !important;
}

#english-result-container,
#english-import-container {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(23, 19, 16, 0.85);
  z-index: 1000;
  align-items: center;
  justify-content: center;
}

#english-result-container[style*="display: block"],
#english-result-container[style*="display: flex"],
#english-import-container[style*="display: block"],
#english-import-container[style*="display: flex"] {
  display: flex !important;
}

[data-theme="dark"] #import-container {
  background-color: rgba(10, 9, 8, 0.9);
}

[data-theme="dark"] #english-result-container,
[data-theme="dark"] #english-import-container {
  background-color: rgba(10, 9, 8, 0.9);
}

.import-card {
  background-color: var(--paper);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  max-width: 520px;
  width: 90%;
  border: var(--rule);
  box-shadow: 0 20px 60px rgba(23, 19, 16, 0.4);
}

[data-theme="dark"] .import-card {
  background-color: var(--paper);
  border-color: var(--ink-soft);
}

.import-title {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--red);
  margin-bottom: var(--spacing-md);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.import-desc {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-md);
  line-height: 1.6;
}

.import-textarea {
  width: 100%;
  min-height: 160px;
  padding: var(--spacing-sm);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--color-bg-secondary);
  color: var(--color-text);
  font-family: var(--font-family-mono);
  font-size: 0.85rem;
  line-height: 1.6;
  resize: vertical;
  outline: none;
  transition: border-color var(--transition-fast);
}

.import-textarea:focus {
  border-color: var(--red);
}

.import-textarea::placeholder {
  color: var(--color-text-muted);
}

.import-actions {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
  flex-wrap: wrap;
}

.import-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  border: var(--rule);
  border-radius: var(--radius-md);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  font-family: var(--font-family);
  font-weight: 800;
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.import-btn:hover {
  background-color: var(--color-key-hover);
  color: var(--color-text);
  border-color: var(--red);
}

.import-btn-primary {
  background-color: var(--red);
  color: #fff;
  border-color: var(--red);
}

.import-btn-primary:hover {
  background-color: var(--red-deep);
  color: #fff;
  border-color: var(--red-deep);
}

.import-msg {
  font-size: 0.8rem;
  margin-top: var(--spacing-sm);
  min-height: 1.2em;
}

.import-msg-error {
  color: var(--red);
}

.import-msg-success {
  color: var(--color-correct);
}

/* ========================================
   响应式适配
   ======================================== */
@media (max-width: 768px) {
  .app-container {
    padding: var(--spacing-sm);
  }

  .app-title {
    font-size: 1.2rem;
  }

  .en-current-zh {
    font-size: 1.75rem;
  }

  .en-current-en {
    font-size: 1rem;
  }

  .en-word-list {
    grid-template-columns: 1fr;
  }

  .pt-text {
    font-size: 1.1rem;
    line-height: 2;
    letter-spacing: 1px;
  }

  .kb-keyboard {
    padding: var(--spacing-sm);
    transform: scale(0.85);
    transform-origin: top center;
  }

  .kb-key {
    width: 40px;
    height: 40px;
    font-size: 0.75rem;
  }

  .kb-key-wide {
    min-width: 60px;
  }

  .kb-key-space {
    width: 180px;
    min-width: 140px;
  }
}

@media (max-width: 480px) {
  .kb-keyboard {
    transform: scale(0.7);
    transform-origin: top center;
  }

  .kb-key {
    width: 36px;
    height: 36px;
    font-size: 0.7rem;
  }

  .kb-key-wide {
    min-width: 52px;
  }

  .kb-key-space {
    width: 140px;
    min-width: 100px;
  }

  .app-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .tb-toolbar {
    width: 100%;
  }
}

/* ========================================
   滚动条美化
   ======================================== */
::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background-color: var(--paper);
}

::-webkit-scrollbar-thumb {
  background-color: var(--paper-3);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background-color: var(--ink-soft);
}