*{margin:0;padding:0;box-sizing:border-box}
/* 禁用微信内置浏览器的文字自动放大（Font Boosting）：
   否则首次进入页面文字被擅自放大，第一次点击后重新布局变小，导致需要再点一次 */
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
:root{
  --bg:#1a1a2e;--card:#16213e;--accent:#e94560;--accent2:#0f3460;
  --gold:#f0a500;--green:#4ecca3;--text:#eee;--sub:#a0a0b8;
  --border:#2a2a4a;--correct:#4ecca3;--wrong:#e94560;
}
body{
  font-family:'Segoe UI','Microsoft YaHei',sans-serif;
  background:var(--bg);color:var(--text);
  /* 老版微信内核不支持 dvh，先回退 100vh 再用 dvh 覆盖 */
  height:100vh;height:100dvh;
  display:flex;flex-direction:column;overflow:hidden;
}
.header{
  background:var(--card);border-bottom:2px solid var(--border);
  padding:8px 16px;display:flex;align-items:center;
  justify-content:space-between;flex-wrap:wrap;gap:6px;flex-shrink:0;
}
.header h1{
  font-size:1.2rem;
  background:linear-gradient(135deg,var(--accent),var(--gold));
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;
}
.header-controls{display:flex;align-items:center;gap:10px;flex-wrap:wrap}

/* 登录区域 */
.login-area{position:relative;display:flex;align-items:center}
.login-btn{
  padding:6px 12px;border:2px solid var(--green);border-radius:8px;
  background:rgba(78,204,163,.1);color:var(--green);cursor:pointer;
  font-size:.75rem;font-weight:bold;transition:all .3s;white-space:nowrap;
}
@media (hover:hover){.login-btn:hover{background:var(--green);color:#1a1a2e;box-shadow:0 0 12px rgba(78,204,163,.4)}}
.login-popup{
  position:absolute;top:100%;left:0;margin-top:4px;
  background:var(--card);border:1.5px solid var(--border);border-radius:10px;
  padding:8px;display:flex;gap:6px;z-index:100;box-shadow:0 4px 20px rgba(0,0,0,.4);
}
.login-popup input{
  padding:4px 8px;border:1.5px solid var(--border);border-radius:6px;
  background:var(--bg);color:var(--text);font-size:.8rem;outline:none;
  width:130px;
}
.login-popup input:focus{border-color:var(--green)}
.logged-in-area{display:flex;align-items:center;gap:6px}
.user-name{
  color:var(--green);font-weight:bold;font-size:.78rem;
  max-width:100px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;
}
.logout-btn{
  background:none;border:1px solid var(--border);color:var(--sub);
  padding:3px 6px;border-radius:6px;cursor:pointer;font-size:.75rem;
  transition:all .2s;
}
@media (hover:hover){.logout-btn:hover{color:var(--accent);border-color:var(--accent)}}
.direction-btn{
  padding:6px 12px;border:2px solid var(--accent);border-radius:8px;
  background:rgba(233,69,96,.1);color:var(--accent);cursor:pointer;
  font-size:.78rem;font-weight:bold;transition:all .3s;white-space:nowrap;
}
@media (hover:hover){
.direction-btn:hover{
  background:var(--accent);color:#fff;
  box-shadow:0 0 15px rgba(233,69,96,.4);
}
}
.auto-speak-btn{
  padding:6px 10px;border:2px solid var(--gold);border-radius:8px;
  background:rgba(240,165,0,.1);color:var(--gold);cursor:pointer;
  font-size:.9rem;transition:all .3s;white-space:nowrap;line-height:1;
}
@media (hover:hover){
.auto-speak-btn:hover{
  background:var(--gold);color:var(--bg);
  box-shadow:0 0 12px rgba(240,165,0,.4);
}
}
.auto-speak-btn.off{
  border-color:var(--border);color:var(--sub);background:rgba(42,42,74,.3);opacity:.6;
}
@media (hover:hover){
.auto-speak-btn.off:hover{
  border-color:var(--gold);color:var(--gold);background:rgba(240,165,0,.1);opacity:1;
}
}
.header-stats{display:flex;gap:12px;font-size:.75rem;color:var(--sub);align-items:center}
.header-stats span{color:var(--gold);font-weight:bold}
#resetStatsBtn{
  background:none;border:1px solid var(--border);color:var(--sub);
  padding:3px 6px;border-radius:6px;cursor:pointer;font-size:.75rem;
  transition:all .2s;
}
@media (hover:hover){#resetStatsBtn:hover{color:var(--accent);border-color:var(--accent)}}
.main-container{
  max-width:900px;margin:0 auto;padding:10px 16px;
  flex:1;display:flex;flex-direction:column;overflow:hidden;min-height:0;
}

/* Home View */
.home-view{
  flex:1;display:flex;flex-direction:column;
  /* overflow-y:scroll 恒定保留滚动条位置：避免滚动条出现/消失导致内容宽度跳变（微信老内核经典滚动条占位，元素会横移） */
  overflow-y:scroll;
  max-width:900px;margin:0 auto;padding:20px 16px;width:100%;
}
.home-grid{
  display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));
  gap:16px;
}
.level-card{
  background:var(--card);border:2px solid var(--border);border-radius:16px;
  padding:24px 20px;cursor:pointer;transition:all .3s;
  display:flex;flex-direction:column;align-items:center;gap:8px;
  position:relative;overflow:hidden;
}
@media (hover:hover){
.level-card:hover{
  border-color:var(--accent);
  box-shadow:0 8px 24px rgba(233,69,96,.2);
}
}
.level-card.completed{border-color:var(--green)}
.level-card-num{
  font-size:2.5rem;font-weight:900;
  background:linear-gradient(135deg,var(--accent),var(--gold));
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;
  line-height:1;
}
.level-card-name{font-size:1.1rem;font-weight:bold;color:var(--text)}
.level-card-desc{font-size:.78rem;color:var(--sub);text-align:center;line-height:1.4}
.level-card-progress{font-size:.72rem;color:var(--gold);margin-top:4px}
.level-card-badge{position:absolute;top:12px;right:12px;font-size:1.2rem}
.level-card .loading-hint{font-size:.7rem;color:var(--sub);margin-top:6px;opacity:.7}

/* Study View */
.study-view{
  max-width:900px;margin:0 auto;padding:10px 16px;
  flex:1;display:flex;flex-direction:column;overflow:hidden;min-height:0;
}
.study-header-bar{
  display:flex;align-items:center;gap:10px;margin-bottom:6px;flex-shrink:0;
}
.home-btn{
  padding:6px 12px;border:2px solid var(--border);border-radius:8px;
  background:var(--card);color:var(--text);cursor:pointer;
  font-size:.85rem;transition:all .3s;white-space:nowrap;
}
@media (hover:hover){.home-btn:hover{border-color:var(--accent);background:rgba(233,69,96,.1)}}
.level-selector{
  flex:1;padding:6px 12px;border:2px solid var(--border);border-radius:8px;
  background:var(--card);color:var(--text);font-size:.82rem;
  cursor:pointer;outline:none;transition:border-color .3s;
}
.level-selector:focus{border-color:var(--accent)}
.level-selector option{background:var(--card);color:var(--text)}

/* Level Bar */
.level-bar{display:flex;gap:4px;margin-bottom:6px;flex-wrap:wrap;justify-content:center;flex-shrink:0}
.level-btn{
  padding:5px 10px;border:1.5px solid var(--border);border-radius:7px;
  background:var(--card);color:var(--text);cursor:pointer;
  font-size:.7rem;transition:all .3s;white-space:nowrap;position:relative;
}
@media (hover:hover){.level-btn:hover{border-color:var(--accent)}}
.level-btn.active{border-color:var(--accent);background:var(--accent);color:#fff;box-shadow:0 0 12px rgba(233,69,96,.4)}
.level-btn.locked{opacity:.4;cursor:not-allowed}
.level-btn.completed{border-color:var(--green)}
.level-btn.completed::after{content:'✓';position:absolute;top:-5px;right:-5px;font-size:.55rem;color:var(--green);background:var(--bg);border-radius:50%;width:14px;height:14px;display:flex;align-items:center;justify-content:center}

/* Category Bar */
.category-bar{display:flex;gap:4px;margin-bottom:4px;flex-wrap:wrap;justify-content:center;flex-shrink:0}
.category-bar:empty{display:none}
.category-btn{
  padding:4px 8px;border:1.5px solid var(--border);border-radius:6px;
  background:var(--card);color:var(--sub);cursor:pointer;
  font-size:.65rem;white-space:nowrap;transition:all .2s;
}
@media (hover:hover){.category-btn:hover{border-color:var(--accent);color:var(--text)}}
.category-btn.active{border-color:var(--accent);background:rgba(233,69,96,.15);color:var(--accent);font-weight:bold}

/* Chapter Bar */
.chapter-bar{display:flex;gap:3px;margin-bottom:6px;flex-wrap:wrap;justify-content:center;flex-shrink:0}
.chapter-bar:empty{display:none}
.chapter-btn{
  padding:3px 7px;border:1.5px solid var(--border);border-radius:5px;
  background:var(--card);color:var(--sub);cursor:pointer;
  font-size:.6rem;white-space:nowrap;transition:all .2s;
}
@media (hover:hover){.chapter-btn:hover{border-color:var(--gold);color:var(--text)}}
.chapter-btn.active{border-color:var(--gold);background:rgba(240,165,0,.15);color:var(--gold);font-weight:bold}
.chapter-btn.completed{border-color:var(--green);color:var(--green);background:rgba(46,204,113,.08)}
.chapter-btn.completed.active{border-color:var(--gold);background:rgba(240,165,0,.15);color:var(--gold)}

/* Progress */
.progress-bar{width:100%;height:5px;background:var(--border);border-radius:3px;margin:4px 0;overflow:hidden;flex-shrink:0}
.progress-fill{height:100%;background:linear-gradient(90deg,var(--accent),var(--gold));border-radius:3px;transition:width .5s}
.progress-row{display:flex;align-items:center;justify-content:center;gap:8px;font-size:0.8rem;color:var(--sub);margin-bottom:10px}
.reset-ch-btn{padding:2px 8px;border:1.5px solid var(--border);border-radius:5px;background:transparent;color:var(--sub);cursor:pointer;font-size:.65rem;transition:all .2s;white-space:nowrap}
@media (hover:hover){.reset-ch-btn:hover{border-color:var(--accent);color:var(--accent)}}

/* Card - scrollable content area */
.card{
  background:var(--card);border:1px solid var(--border);
  border-radius:12px;padding:16px;text-align:center;
  /* overflow-y:scroll 恒定保留滚动条：切题时内容高度临界变化不会引发滚动条震荡、按钮位置横移 */
  flex:1;display:flex;flex-direction:column;overflow-y:scroll;min-height:0;
}

/* Loading Spinner */
.loading-spinner{
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  padding:40px 20px;gap:16px;
}
.spinner{
  width:40px;height:40px;border:3px solid var(--border);
  border-top-color:var(--gold);border-radius:50%;
  animation:spin 1s linear infinite;
}
@keyframes spin{to{transform:rotate(360deg)}}
.loading-text{color:var(--sub);font-size:.85rem}

/* Content Fade In：纯透明度渐变，不带位移（避免微信内置浏览器等环境下切题时元素位置跳动导致点偏） */
#contentCard{animation:fadeIn .3s ease-out}
@keyframes fadeIn{from{opacity:0}to{opacity:1}}
/* 禁用双击缩放等默认手势（微信内置浏览器快速点击会触发页面缩放） */
*{touch-action:manipulation}

/* Mode Tabs */
.mode-tabs{display:flex;gap:0;margin-bottom:8px;border-radius:8px;overflow:hidden;flex-shrink:0}
.mode-tab{
  flex:1;padding:8px;border:none;background:var(--card);color:var(--sub);
  cursor:pointer;font-size:.78rem;transition:all .3s;border-bottom:3px solid transparent;
}
@media (hover:hover){.mode-tab:hover{color:var(--text)}}
.mode-tab.active{color:var(--accent);border-bottom-color:var(--accent);background:rgba(233,69,96,.1)}

/* Flashcard */
.flashcard{margin:0 auto;width:100%;max-width:500px;flex:1;display:flex;flex-direction:column;justify-content:center}
.flashcard-single{
  background:linear-gradient(135deg,var(--accent2),var(--card));
  border:2px solid var(--border);border-radius:12px;
  padding:20px;min-height:140px;
  display:flex;flex-direction:column;align-items:center;justify-content:center;
}
.flashcard-face{
  background:linear-gradient(135deg,var(--accent2),var(--card));
  border:2px solid var(--border);border-radius:12px;
  padding:20px;cursor:pointer;min-height:140px;
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  transition:all .3s;
}
@media (hover:hover){.flashcard-face:hover{border-color:var(--accent)}}
.word-vi{font-size:1.8rem;font-weight:bold;color:var(--gold);margin-bottom:6px}
.word-zh{font-size:1.1rem;color:var(--text);margin-bottom:4px}
.word-ipa{font-size:.85rem;color:var(--sub);font-style:italic}
.word-ex{font-size:.75rem;color:var(--sub);margin-top:8px;line-height:1.4}
.flashcard-hint{font-size:.7rem;color:var(--sub);margin-top:8px;opacity:.6}

/* Typing */
.typing-prompt{font-size:.9rem;color:var(--sub);margin-bottom:4px}
.typing-target{font-size:1.6rem;font-weight:bold;color:var(--gold);margin-bottom:8px;min-height:36px;letter-spacing:1px}
.typing-target .c-correct{color:var(--correct)}
.typing-target .c-wrong{color:var(--wrong);position:relative;display:inline-block}
.typing-target .c-wrong small{color:#888;display:block;line-height:1;font-size:.45em}
.typing-target .c-extra{text-decoration:line-through;text-decoration-color:var(--wrong)}
.typing-target .c-current{color:var(--accent);border-bottom:2px solid var(--accent);animation:blink .8s infinite}
.typing-target .c-pending{color:var(--pending, #a0a0b8)}
@keyframes blink{0%,100%{opacity:1}50%{opacity:.3}}

.typing-input{
  width:100%;max-width:500px;padding:10px 16px;font-size:1.1rem;
  border:2px solid var(--border);border-radius:10px;
  background:var(--bg);color:var(--text);outline:none;
  text-align:center;letter-spacing:1px;transition:border-color .3s;
}
.typing-input:focus{border-color:var(--accent)}
.typing-input.correct-flash{border-color:var(--correct);background:rgba(78,204,163,.1)}
.typing-input.wrong-flash{border-color:var(--wrong);background:rgba(233,69,96,.1)}

.typing-info{display:flex;gap:12px;justify-content:center;margin-top:6px;font-size:.72rem;color:var(--sub);flex-wrap:wrap}
.typing-info .val{color:var(--gold);font-weight:bold}

/* Test */
.test-results{display:none;margin-top:12px;padding:14px;background:rgba(78,204,163,.1);border:1px solid var(--green);border-radius:10px}
.test-results.show{display:block}
.test-results .score{font-size:2rem;font-weight:bold;color:var(--green)}
.test-results .detail{display:flex;gap:16px;justify-content:center;margin-top:8px;flex-wrap:wrap}
.detail-item{text-align:center}
.detail-val{font-size:1.2rem;font-weight:bold;color:var(--gold)}
.detail-label{font-size:.7rem;color:var(--sub)}

/* Review */
.review-item{display:flex;gap:8px;align-items:center;padding:6px;margin:4px 0;border-radius:6px;text-align:left}
.review-item.correct{background:rgba(78,204,163,.1)}
.review-item.wrong{background:rgba(233,69,96,.1)}
.review-item .ri-q{font-weight:bold;color:var(--gold);min-width:120px;font-size:.85rem}
.review-item .ri-a{color:var(--sub);flex:1;font-size:.85rem}

/* Buttons */
.btn{
  padding:8px 18px;border:none;border-radius:8px;cursor:pointer;
  font-size:.82rem;font-weight:bold;transition:all .3s;margin:3px;
}
.btn-primary{background:var(--accent);color:#fff}
@media (hover:hover){.btn-primary:hover{box-shadow:0 0 16px rgba(233,69,96,.5)}}
.btn-secondary{background:var(--accent2);color:var(--text);border:1px solid var(--border)}
.btn-green{background:var(--green);color:#1a1a2e}
@media (hover:hover){.btn-green:hover{box-shadow:0 0 16px rgba(78,204,163,.5)}}
.btn-sm{padding:4px 10px;font-size:.7rem}
.btn:disabled{opacity:.4;cursor:not-allowed;transform:none!important;box-shadow:none!important}

.footer-nav{display:flex;gap:8px;justify-content:center;margin-top:8px;flex-wrap:wrap;flex-shrink:0}

/* Level desc */
.level-desc{font-size:.75rem;color:var(--sub);margin-bottom:8px;flex-shrink:0}
.cat-tag{display:inline-block;background:var(--accent2);color:var(--green);font-size:.65rem;padding:1px 6px;border-radius:8px;margin-left:4px;font-weight:500;vertical-align:middle}

/* Streak */
.streak-badge{
  display:inline-block;padding:3px 10px;background:var(--accent2);
  border-radius:16px;font-size:.7rem;color:var(--gold);margin:4px;
}

/* Wrong Badge */
.wrong-badge{
  display:inline-block;background:var(--accent);color:#fff;
  border-radius:8px;padding:1px 5px;font-size:.65rem;
  font-weight:bold;margin-left:3px;vertical-align:middle;
  line-height:1.3;
}

/* 发音按钮 */
.word-row{display:flex;align-items:center;justify-content:center;gap:8px;margin-bottom:6px;flex-wrap:wrap}
.word-row .word-vi{margin-bottom:0}
.word-row .word-zh{margin-bottom:0}
.speak-group{display:flex;gap:4px;flex-shrink:0}
.btn-speak{
  width:36px;height:36px;border:2px solid var(--gold);border-radius:50%;
  background:rgba(240,165,0,.1);color:var(--gold);cursor:pointer;
  font-size:.9rem;transition:all .3s;display:inline-flex;
  align-items:center;justify-content:center;flex-shrink:0;
  line-height:1;padding:0;
}
.btn-speak svg{width:16px;height:16px;fill:var(--gold)}
@media (hover:hover){
.btn-speak:hover{
  background:var(--gold);color:var(--bg);
  box-shadow:0 0 12px rgba(240,165,0,.4);
}
.btn-speak:hover svg{fill:var(--bg)}
}
.btn-speak-sm{
  width:auto;height:28px;border-radius:14px;padding:0 10px;
  font-size:.7rem;border:1.5px solid var(--gold);
  background:rgba(240,165,0,.08);color:var(--gold);
  cursor:pointer;transition:all .3s;white-space:nowrap;
  display:inline-flex;align-items:center;gap:4px;
}
.btn-speak-sm svg{width:12px;height:12px;fill:var(--gold)}
@media (hover:hover){
.btn-speak-sm:hover{
  background:var(--gold);color:var(--bg);
  box-shadow:0 0 10px rgba(240,165,0,.3);
}
.btn-speak-sm:hover svg{fill:var(--bg)}
}

.word-row{flex-wrap:wrap}

/* Toast 非阻塞提示 */
.toast-box{
  position:fixed;left:50%;bottom:48px;transform:translateX(-50%) translateY(20px);
  background:rgba(22,33,62,.96);border:1.5px solid var(--gold);border-radius:10px;
  padding:10px 18px;color:var(--text);font-size:.85rem;white-space:pre-line;
  box-shadow:0 4px 20px rgba(0,0,0,.5);z-index:999;max-width:86vw;
  opacity:0;pointer-events:none;transition:opacity .3s,transform .3s;text-align:center;
}
.toast-box.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* 看图选词游戏模式 */
.pic-game{display:flex;flex-direction:column;align-items:center;gap:10px;padding:8px 0}
.pic-score-row{display:flex;gap:16px;font-size:.85rem;color:var(--sub)}
.pic-score-row .val{color:var(--gold);font-weight:bold}
.pic-combo{color:var(--accent);font-weight:bold;min-width:64px;text-align:center}
.pic-combo.hot{animation:comboPop .4s ease-out}
@keyframes comboPop{0%{transform:scale(1.6)}100%{transform:scale(1)}}
.pic-stage{
  width:150px;height:150px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;
  background:radial-gradient(circle,rgba(240,165,0,.12),rgba(22,33,62,.6));
  border:2px solid var(--border);border-radius:20px;line-height:1;
  animation:fadeIn .3s ease-out;user-select:none;
}
.pic-stage .pic-emoji{font-size:4.4rem;line-height:1.1}
.pic-stage .pic-word{font-size:1.25rem;font-weight:bold;color:var(--gold);max-width:90%;text-align:center;word-break:break-word}
.pic-stage.listen-mode{font-size:3rem;cursor:pointer;transition:all .2s;flex-direction:row}
/* 回退题（无 emoji）：源语言文字作为主要作答依据，字号比看图题更大 */
.listen-word{font-size:1.6rem;font-weight:bold;color:var(--gold);text-align:center;max-width:90%;word-break:break-word;line-height:1.3}
@media (hover:hover){.pic-stage.listen-mode:hover{border-color:var(--gold)}}
.pic-hint{font-size:.8rem;color:var(--sub)}
.pic-options{display:grid;grid-template-columns:1fr 1fr;gap:10px;width:100%;max-width:480px}
.pic-option{
  padding:14px 10px;border:2px solid var(--border);border-radius:12px;
  background:var(--card);color:var(--text);cursor:pointer;font-size:1.05rem;
  transition:border-color .2s,background-color .2s,color .2s;text-align:center;word-break:break-word;
}
@media (hover:hover){.pic-option:hover{border-color:var(--gold)}}
/* 注意：不用 font-weight:bold，避免文字变宽导致选项网格重排、点击位置偏移 */
.pic-option.correct{border-color:var(--green);background:rgba(78,204,163,.18);color:var(--green)}
.pic-option.wrong{border-color:var(--wrong);background:rgba(233,69,96,.15);color:var(--wrong);animation:shake .35s}
.pic-option.reveal{border-color:var(--green);color:var(--green)}
.pic-option:disabled{cursor:default}
@keyframes shake{0%,100%{transform:translateX(0)}25%{transform:translateX(-6px)}75%{transform:translateX(6px)}}
.pic-feedback{font-size:1rem;font-weight:bold;min-height:1.4em}
.pic-feedback.good{color:var(--green)}
.pic-feedback.bad{color:var(--wrong)}
/* 看图选词完成界面 */
.pic-complete-icon{font-size:4.5rem;line-height:1.2;animation:comboPop .5s ease-out}
.pic-complete-title{font-size:1.15rem;font-weight:bold;color:var(--gold);margin:4px 0 8px}
.pic-complete-btns{display:flex;gap:12px;justify-content:center;margin-top:14px;flex-wrap:wrap}

@media(max-width:767px){
  /* 手机端输入聚焦时，隐藏非必要UI，腾出空间给内容和键盘 */
  body.input-focused .header-controls{display:none}
  body.input-focused .header h1{font-size:1rem}
  .study-view:focus-within .study-header-bar{margin-bottom:2px}
  .study-view:focus-within .category-bar{display:none}
  .study-view:focus-within .chapter-bar{display:none}
  .study-view:focus-within .progress-bar+div{display:none}
  .study-view:focus-within .mode-tabs{display:none}
  .study-view:focus-within .level-desc{display:none}
  /* 看图选词：小屏幕紧凑布局 */
  .pic-stage{width:132px;height:132px;border-radius:14px}
  .pic-stage .pic-emoji{font-size:3.8rem}
  .pic-stage .pic-word{font-size:1rem}
  .listen-word{font-size:1.3rem}
  .pic-stage.listen-mode{font-size:2.2rem}
  .pic-game{gap:7px}
  .pic-option{padding:11px 8px;font-size:.95rem}
  .pic-hint{font-size:.72rem}
  /* 卡片内容确保可滚动 */
  .card{overflow-y:scroll;-webkit-overflow-scrolling:touch}
  /* 底部导航紧凑 */
  .footer-nav{margin-top:4px}
  .footer-nav .btn{padding:6px 12px;font-size:.75rem}
}

@media(min-width:768px){
  .card{padding:24px}
  .flashcard-face, .flashcard-single{padding:28px;min-height:160px}
  .word-vi{font-size:2.2rem}
  .word-zh{font-size:1.2rem}
  .typing-target{font-size:2rem}
  .typing-input{padding:12px 20px;font-size:1.2rem}
  .btn-speak{width:40px;height:40px;font-size:1rem}
  .level-btn{padding:8px 16px;font-size:.8rem}
  .category-btn{padding:5px 12px;font-size:.72rem}
  .header h1{font-size:1.4rem}
  .level-card{padding:32px 24px}
  .level-card-num{font-size:3rem}
  .level-card-name{font-size:1.25rem}
  .level-card-desc{font-size:.85rem}
  .home-grid{grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:20px}
}