:root{
  --paper:#faf7f0; --card:#fffdf8; --ink:#2b2620; --muted:#8a7f6d;
  --red:#b03a2e; --red-soft:#f6e3df; --line:#e6ddcd; --gold:#b98a2f;
  --done:#3e7d4e;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{background:var(--paper);color:var(--ink);font-family:"PingFang SC","Microsoft YaHei","Noto Sans SC",system-ui,sans-serif;min-height:100vh;display:flex;flex-direction:column}
a{color:var(--red)}
button{font-family:inherit;cursor:pointer}

.topbar{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:18px 28px;border-bottom:1px solid var(--line);flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:14px}
.seal{display:inline-flex;align-items:center;justify-content:center;width:48px;height:48px;background:var(--red);color:#fff;font-family:"Noto Serif SC","Songti SC",serif;font-size:26px;font-weight:700;border-radius:8px;box-shadow:0 2px 8px rgba(176,58,46,.3)}
.seal.big{width:64px;height:64px;font-size:36px}
.brand h1{margin:0;font-family:"Noto Serif SC","Songti SC",serif;font-size:26px;letter-spacing:2px}
.brand p{margin:2px 0 0;color:var(--muted);font-size:13px}
.top-actions{display:flex;align-items:center;gap:12px}
.ghost-btn{background:transparent;border:1px solid var(--line);border-radius:8px;padding:7px 14px;font-size:14px;color:var(--ink)}
.ghost-btn:hover{border-color:var(--red);color:var(--red)}
.primary-btn{background:var(--red);color:#fff;border:0;border-radius:8px;padding:10px 22px;font-size:15px}
.primary-btn:hover{background:#933025}

main{flex:1;width:100%;max-width:880px;margin:0 auto;padding:28px 20px 40px}
.intro{color:var(--muted);font-size:15px;line-height:1.7;margin:0 0 22px}

.mode-tabs{display:flex;gap:10px;margin:0 0 18px}
.mode-tab{border:1px solid var(--line);background:var(--card);border-radius:24px;padding:9px 22px;font-size:15px;font-family:"Noto Serif SC","Songti SC",serif;letter-spacing:1px;color:var(--muted)}
.mode-tab.active{background:var(--red);border-color:var(--red);color:#fff}

.shelf-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px}
.shelf-levels{grid-template-columns:repeat(auto-fill,minmax(300px,1fr))}
.level-card{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:20px;transition:border-color .15s,transform .15s}
.level-card:hover{border-color:var(--red);transform:translateY(-2px)}
.level-card h3{margin:0 0 4px;font-family:"Noto Serif SC","Songti SC",serif;font-size:22px;letter-spacing:1px}
.level-card .sub{color:var(--muted);font-size:13px;margin:0 0 12px}
.level-card .meta-row{display:flex;justify-content:space-between;align-items:center;font-size:12px;color:var(--muted)}
.level-tag{border:1px solid var(--gold);color:var(--gold);border-radius:20px;padding:2px 10px;font-size:12px}
.level-card .done-tag{color:var(--done);font-weight:600}
.level-card .bar{height:5px;background:var(--line);border-radius:3px;margin:12px 0 16px;overflow:hidden}
.level-card .bar i{display:block;height:100%;background:var(--done)}
.card-actions{display:flex;gap:10px;align-items:center}
.card-actions .primary-btn{padding:8px 18px;font-size:14px}
.reset-btn{background:transparent;border:0;color:var(--muted);font-size:13px;padding:6px 4px}
.reset-btn:hover{color:var(--red);text-decoration:underline}

.reader-head{display:flex;align-items:flex-start;justify-content:space-between;gap:12px;margin-bottom:14px}
.reader-title{text-align:center}
.reader-title h2{margin:0;font-family:"Noto Serif SC","Songti SC",serif;font-size:28px;letter-spacing:3px}
.reader-title p{margin:4px 0 0;color:var(--muted);font-size:13px}
.reader-actions{display:flex;gap:8px}

.stats{display:flex;gap:10px;justify-content:center;margin-bottom:10px;flex-wrap:wrap}
.stat{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:8px 18px;text-align:center;min-width:92px}
.stat-num{display:block;font-size:19px;font-weight:700}
.stat-label{font-size:11px;color:var(--muted)}
.progress-track{height:6px;background:var(--line);border-radius:3px;overflow:hidden;margin-bottom:22px}
#progressBar{height:100%;width:0;background:var(--red);transition:width .2s}

#wordCard{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:34px 28px 24px;position:relative;outline:none;text-align:center}
#wordCard:focus{border-color:var(--gold)}
#wordCard.fresh{animation:pulse-border 1.6s ease-in-out infinite}
@keyframes pulse-border{0%,100%{border-color:var(--line)}50%{border-color:var(--red)}}
.slots{display:flex;flex-wrap:wrap;gap:6px;justify-content:center;min-height:52px}
.slot{display:inline-flex;align-items:flex-end;justify-content:center;width:34px;height:50px;font-family:Georgia,"Times New Roman",serif;font-size:32px;color:var(--ink);border-bottom:3px solid var(--line);transition:border-color .15s,color .15s}
.slot.current{border-bottom-color:var(--red)}
.slot.done{color:var(--done);border-bottom-color:var(--done)}
.slot.err{color:var(--red);border-bottom-color:var(--red);animation:shake .25s}
@keyframes shake{0%,100%{transform:translateX(0)}25%{transform:translateX(-4px)}75%{transform:translateX(4px)}}
.phonetic{font-size:19px;color:var(--muted);margin:16px 0 4px;min-height:26px;font-family:Georgia,serif}
.hint-row{display:flex;justify-content:center;align-items:center;gap:14px;flex-wrap:wrap;margin-top:10px;min-height:26px}
.hint-toggle{font-size:14px;color:var(--muted);display:flex;align-items:center;gap:6px;cursor:pointer}
.hint-toggle input{accent-color:var(--red);width:16px;height:16px}
.meaning{font-size:17px;color:var(--gold);font-weight:600}
.reveal{margin-top:20px;border-top:1px dashed var(--line);padding-top:18px}
.reveal-meaning{font-size:19px;font-weight:600;margin:0 0 8px}
.reveal-ex{font-family:Georgia,serif;font-size:18px;margin:0 0 4px}
.reveal-exzh{color:var(--muted);font-size:15px;margin:0 0 18px}
.kbd-tip{text-align:center;color:var(--muted);font-size:12px;margin:18px 0 4px}
#mobileInput{position:absolute;opacity:0;pointer-events:none;height:1px;width:1px;bottom:0;left:0}

.overlay{position:fixed;inset:0;background:rgba(43,38,32,.55);display:flex;align-items:center;justify-content:center;padding:20px;z-index:10}
.overlay[hidden]{display:none}
.overlay-card{background:var(--card);border-radius:16px;padding:36px 40px;text-align:center;max-width:460px;width:100%}
.overlay-card h2{font-family:"Noto Serif SC","Songti SC",serif;letter-spacing:4px;margin:16px 0 4px}
.done-name{color:var(--muted);margin:0 0 20px}
.done-stats{display:flex;justify-content:center;gap:26px;margin-bottom:14px;flex-wrap:wrap}
.done-stats strong{display:block;font-size:24px}
.done-stats span{font-size:12px;color:var(--muted)}
.done-note{color:var(--muted);font-size:13px;margin:0 0 22px}
.done-actions{display:flex;gap:12px;justify-content:center}

footer{border-top:1px solid var(--line);padding:20px 28px;text-align:center;color:var(--muted);font-size:13px}
.foot-links{display:flex;flex-wrap:wrap;gap:8px 20px;justify-content:center;align-items:center;margin-bottom:12px}
.foot-label{font-weight:600;color:var(--ink)}
.foot-links a{color:var(--muted);text-decoration:none}
.foot-links a:hover{color:var(--red);text-decoration:underline}

@media (max-width:560px){
  main{padding:20px 14px 32px}
  #wordCard{padding:24px 14px 16px}
  .slot{width:23px;height:38px;font-size:22px}
  .slots{gap:4px;min-height:40px}
  .phonetic{font-size:16px}
  .stats{gap:6px}
  .stat{min-width:74px;padding:6px 10px}
  .overlay-card{padding:28px 20px}
}