:root {
  --cream-page: #FBF8EE;
  --cream-card: #F6F0DD;
  --cream-card-hi: #FCFAF1;
  --line: #E6DCC0;
  --ink: #23211C;
  --ink-soft: #726B57;
  --maroon: #9E2B25; --maroon-soft: #F2DEDA;
  --gold: #A87C18;   --gold-soft: #F1E4BC;
  --teal: #2C7589;   --teal-soft: #D6E8EE;
  --green: #4E7A3C;  --green-soft: #E0EBD3;
  --radius: 22px; --radius-sm: 14px;
  --shadow: 0 8px 24px rgba(70,56,20,.09), 0 2px 5px rgba(70,56,20,.06);
  --shadow-hi: 0 14px 34px rgba(70,56,20,.16), 0 3px 8px rgba(70,56,20,.08);
}
*{box-sizing:border-box;}
html,body{margin:0;padding:0;}
body{font-family:'Lexend','Noto Sans HK',system-ui,sans-serif;background:var(--cream-page);color:var(--ink);line-height:1.6;letter-spacing:.01em;-webkit-font-smoothing:antialiased;}

/* NAV */
.topnav{display:flex;align-items:center;gap:16px;padding:14px 28px;background:var(--cream-card);border-bottom:1px solid var(--line);}
.nav-brand{font-size:20px;font-weight:800;flex:none;}
.nav-links{display:flex;gap:18px;flex:1;}
.nav-links a{text-decoration:none;font-weight:600;color:var(--teal);font-size:16px;}
.nav-user{font-size:15px;font-weight:700;color:var(--ink-soft);}

/* HUB */
.hub{max-width:980px;margin:0 auto;padding:48px 32px 80px;}
.hub-head{text-align:center;margin-bottom:44px;}
.hub-head .crumb{font-size:15px;font-weight:700;letter-spacing:.14em;text-transform:uppercase;color:var(--gold);margin:0 0 6px;}
.hub-head h1{font-size:54px;font-weight:800;margin:0;line-height:1.15;}
.hub-head h1 span{font-size:32px;font-weight:600;color:var(--ink-soft);}

/* CARDS */
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;}
a.tile{text-decoration:none;color:var(--ink);background:var(--cream-card-hi);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:30px 26px 26px;display:flex;flex-direction:column;transition:transform .14s,box-shadow .14s;}
a.tile:hover{transform:translateY(-5px);box-shadow:var(--shadow-hi);}
.tile-icon{width:64px;height:64px;border-radius:16px;display:flex;align-items:center;justify-content:center;margin-bottom:18px;}
.tile-icon svg{width:34px;height:34px;stroke-width:2.2;}
.tile.t1 .tile-icon{background:var(--gold-soft);color:var(--gold);}
.tile.t2 .tile-icon{background:var(--teal-soft);color:var(--teal);}
.tile.t3 .tile-icon{background:var(--green-soft);color:var(--green);}
.tile.t4 .tile-icon{background:var(--maroon-soft);color:var(--maroon);}
.tile h2{font-size:24px;font-weight:800;margin:0 0 8px;}
.tile h2 small{font-size:16px;font-weight:500;color:var(--ink-soft);display:block;}
.tile p{font-size:16px;color:var(--ink-soft);margin:0 0 18px;flex:1;line-height:1.6;}
.tile .go{font-size:16px;font-weight:700;display:flex;align-items:center;gap:8px;}
.tile.t1 .go{color:var(--gold);}
.tile.t2 .go{color:var(--teal);}
.tile.t3 .go{color:var(--green);}
.tile.t4 .go{color:var(--maroon);}
.tile .go svg{width:18px;height:18px;}

/* AUTH */
.auth-wrap{display:flex;align-items:center;justify-content:center;min-height:100vh;padding:24px;}
.auth-card{background:var(--cream-card-hi);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:48px 44px;width:100%;max-width:440px;}
.auth-logo{font-size:52px;text-align:center;margin-bottom:4px;}
.auth-title{font-size:32px;font-weight:800;text-align:center;margin:0 0 30px;line-height:1.25;}
.auth-title span{font-size:20px;font-weight:500;color:var(--ink-soft);}
.auth-form label{display:block;font-size:15px;font-weight:700;margin-bottom:6px;}
.auth-form input,.auth-form select{display:block;width:100%;padding:14px 16px;border:2px solid var(--line);border-radius:12px;font-family:inherit;font-size:18px;background:#fff;color:var(--ink);margin-bottom:18px;}
.auth-form input:focus,.auth-form select:focus{outline:none;border-color:var(--teal);}

/* BUTTONS */
.btn{font-family:inherit;font-size:18px;font-weight:700;border:none;cursor:pointer;border-radius:14px;padding:14px 24px;min-height:52px;background:var(--ink);color:#fff;display:inline-flex;align-items:center;justify-content:center;gap:10px;transition:transform .12s,box-shadow .12s;text-decoration:none;}
.btn:hover{transform:translateY(-2px);box-shadow:var(--shadow);}
.btn-ghost{background:#fff;color:var(--ink);border:2px solid var(--line);}
.btn-sm{font-size:15px;padding:10px 18px;min-height:40px;}
.btn-full{width:100%;}

/* ALERTS */
.alert{padding:14px 18px;border-radius:12px;margin-bottom:18px;font-weight:600;font-size:16px;}
.alert-ok{background:var(--green-soft);color:#2f4a1d;}
.alert-error{background:var(--maroon-soft);color:var(--maroon);}

/* USER LIST */
.user-list{display:flex;flex-direction:column;gap:10px;margin-top:12px;}
.user-row{display:flex;align-items:center;gap:14px;background:var(--cream-card-hi);border:1px solid var(--line);border-radius:14px;padding:14px 18px;}
.user-name{font-weight:700;font-size:17px;flex:none;}
.user-email{color:var(--ink-soft);font-size:15px;flex:1;}
.badge{font-size:12px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;padding:4px 10px;border-radius:999px;}
.badge-child{background:var(--teal-soft);color:var(--teal);}
.badge-admin{background:var(--gold-soft);color:var(--gold);}
.badge-superadmin{background:var(--maroon-soft);color:var(--maroon);}

/* AI PAGES */
.ai-wrap{max-width:760px;margin:0 auto;padding:32px 24px 80px;}
.ai-header{display:flex;align-items:center;gap:16px;margin-bottom:24px;flex-wrap:wrap;}
.ai-header h1{font-size:28px;font-weight:800;margin:0;flex:1;}
.ai-header h1 span{font-size:18px;font-weight:500;color:var(--ink-soft);}
.lang-toggle{display:flex;gap:8px;}
.lang-btn{font-family:inherit;font-size:14px;font-weight:700;padding:8px 16px;border-radius:999px;border:2px solid var(--line);background:#fff;cursor:pointer;}
.lang-btn.active{background:var(--teal);color:#fff;border-color:var(--teal);}

/* UPLOAD */
.upload-zone{border:2px dashed var(--line);border-radius:var(--radius);padding:40px;text-align:center;cursor:pointer;background:var(--cream-card);transition:border-color .2s;}
.upload-zone:hover{border-color:var(--teal);}
.upload-zone p{margin:12px 0 0;font-size:18px;font-weight:600;}
.upload-zone small{font-size:14px;color:var(--ink-soft);}
.thumb-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(96px,1fr));gap:10px;}
.thumb{position:relative;aspect-ratio:3/4;border-radius:12px;overflow:hidden;border:1px solid var(--line);background:var(--cream-card);}
.thumb img{width:100%;height:100%;object-fit:cover;display:block;}
.thumb-num{position:absolute;left:6px;bottom:6px;background:rgba(0,0,0,.6);color:#fff;font-size:13px;font-weight:700;border-radius:8px;padding:1px 7px;}
.thumb-rm{position:absolute;top:4px;right:4px;width:30px;height:30px;border-radius:50%;border:none;background:rgba(0,0,0,.6);color:#fff;font-size:15px;cursor:pointer;}
.thumb-add{border:2px dashed var(--line);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;font-size:30px;color:var(--teal);cursor:pointer;font-family:inherit;}
.thumb-add small{font-size:13px;color:var(--ink-soft);}

/* CHAT */
.chat-box{display:flex;flex-direction:column;gap:14px;margin-top:20px;min-height:60px;}
.msg{padding:16px 20px;border-radius:16px;font-size:18px;line-height:1.6;position:relative;max-width:90%;}
.msg-ai{background:var(--cream-card-hi);border:1px solid var(--line);align-self:flex-start;}
.msg-user{background:var(--teal);color:#fff;align-self:flex-end;}
.msg-speak{position:absolute;top:10px;right:10px;background:none;border:none;cursor:pointer;font-size:18px;opacity:.6;}
.msg-speak:hover{opacity:1;}
.chat-input-row{display:flex;gap:10px;margin-top:18px;align-items:center;}
.chat-input-row input{flex:1;padding:14px 18px;border:2px solid var(--line);border-radius:14px;font-family:inherit;font-size:18px;}
.speak-btn{width:52px;height:52px;border-radius:14px;border:2px solid var(--line);background:#fff;cursor:pointer;display:flex;align-items:center;justify-content:center;color:var(--teal);}

/* MAIN */
.main-wrap{padding:0;}
@media(max-width:720px){
  .cards{grid-template-columns:1fr;}
  .hub-head h1{font-size:36px;}
  .hub{padding:32px 18px;}
  .auth-card{padding:32px 24px;}
}

/* writing step info */
.step-info { font-size:16px; font-weight:700; color:var(--teal); background:var(--teal-soft); border-radius:10px; padding:10px 16px; margin-bottom:12px; }
.article-box { background:var(--cream-card-hi); border:1px solid var(--line); border-radius:var(--radius); padding:28px 26px; margin-top:20px; }

/* PDF THUMBS */
.thumb-pdf{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:6px;padding:8px;background:var(--cream-card-hi);}
.thumb-pdf-icon{font-size:34px;}
.thumb-pdf-name{font-size:12px;font-weight:600;text-align:center;word-break:break-all;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden;}

/* QUIZ HISTORY */
.person-tabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:16px;}
.person-tabs a{padding:8px 16px;border-radius:999px;border:2px solid var(--line);text-decoration:none;font-weight:700;color:var(--ink-soft);background:#fff;}
.person-tabs a.active{border-color:var(--teal);color:var(--teal);background:var(--teal-soft);}
.hist-summary{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-bottom:18px;}
.hist-summary div{background:var(--cream-card-hi);border:1px solid var(--line);border-radius:var(--radius-sm);padding:14px 8px;text-align:center;}
.hist-summary b{display:block;font-size:26px;font-weight:800;}
.hist-summary small{font-size:13px;color:var(--ink-soft);}
.hist-list{display:flex;flex-direction:column;gap:12px;}
.hist-card{background:var(--cream-card-hi);border:1px solid var(--line);border-radius:var(--radius-sm);padding:16px 18px;}
.hist-top{display:flex;gap:12px;align-items:flex-start;margin-bottom:10px;}
.hist-top h3{margin:0 0 2px;font-size:18px;overflow-wrap:anywhere;}
.hist-top small{color:var(--ink-soft);font-size:13px;}
.hist-tries{display:flex;flex-wrap:wrap;gap:6px 14px;margin-bottom:10px;font-size:15px;}
.hist-tries a{color:var(--teal);font-weight:600;}
.hist-tries em{color:var(--ink-soft);font-style:normal;font-size:13px;}
.score-pill{flex:none;font-size:14px;font-weight:800;padding:4px 12px;border-radius:999px;}
.score-pill.good{background:var(--green-soft);color:var(--green);}
.score-pill.ok{background:var(--gold-soft);color:var(--gold);}
.score-pill.low{background:var(--maroon-soft);color:var(--maroon);}

/* QUIZ REVIEW */
.review-q{background:var(--cream-card-hi);border:1px solid var(--line);border-left:6px solid var(--line);border-radius:var(--radius-sm);padding:16px 18px;margin-bottom:12px;}
.review-q.right{border-left-color:var(--green);}
.review-q.wrong{border-left-color:var(--maroon);}
.rq-zh{font-size:18px;font-weight:700;margin:0 0 4px;}
.rq-en{font-size:15px;color:var(--ink-soft);font-style:italic;margin:0 0 10px;}
.review-q ul{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:6px;}
.review-q li{padding:8px 12px;border-radius:10px;border:1px solid var(--line);background:#fff;font-size:16px;}
.review-q li.is-answer{background:var(--green-soft);border-color:var(--green);}
.review-q li.is-picked:not(.is-answer){background:var(--maroon-soft);border-color:var(--maroon);}
.rq-tag{display:inline-block;margin-left:6px;font-size:13px;font-weight:700;}
.rq-note{color:var(--ink-soft);font-size:14px;margin:8px 0 0;}
.rq-explain{margin:10px 0 0;font-size:15px;line-height:1.6;}
.rq-explain small{color:var(--ink-soft);}

/* QUESTION COUNT + NEW VERSIONS */
.count-pick{display:inline-flex;border:2px solid var(--line);border-radius:14px;overflow:hidden;background:#fff;}
.count-pick button{font-family:inherit;font-size:16px;font-weight:700;padding:10px 18px;border:none;background:transparent;color:var(--ink-soft);cursor:pointer;min-height:44px;}
.count-pick button+button{border-left:2px solid var(--line);}
.count-pick button.active{background:var(--teal);color:#fff;}
.regen-box{margin:30px auto 0;max-width:420px;padding:18px;border:2px dashed var(--line);border-radius:var(--radius-sm);display:flex;flex-direction:column;align-items:center;gap:12px;}
.regen-box p{margin:0;font-weight:700;}
.regen-box small{font-weight:500;color:var(--ink-soft);}
.regen-msg{margin:0;font-size:14px;color:var(--ink-soft);flex-basis:100%;}
.regen-msg:empty{display:none;}
.hist-version{border-top:1px solid var(--line);padding:10px 0;}
.hv-head{display:flex;flex-wrap:wrap;align-items:center;gap:6px 10px;margin-bottom:6px;}
.hv-head small{color:var(--ink-soft);font-size:13px;}
.hv-head .score-pill{margin-left:auto;}
.regen-row{border-top:1px solid var(--line);padding-top:12px;display:flex;flex-wrap:wrap;align-items:center;gap:10px;}

/* QUESTION TYPES + MISTAKE REVIEW */
.count-pick{flex-wrap:wrap;max-width:100%;}
.qtype-tag{display:inline-block;font-size:12px;font-weight:800;letter-spacing:.04em;padding:2px 8px;margin-right:8px;border-radius:999px;background:var(--teal-soft);color:var(--teal);vertical-align:middle;}
.q-sub{display:inline-block;margin-top:6px;font-size:16px;font-weight:500;font-style:italic;color:var(--ink-soft);}
.blank{display:inline-block;min-width:4.5em;padding:0 8px;margin:0 2px;border-bottom:3px solid var(--teal);background:var(--teal-soft);border-radius:6px 6px 0 0;text-align:center;font-style:normal;}
.blank.ok{border-color:var(--green);background:var(--green-soft);color:var(--green);}
.blank.bad{border-color:var(--maroon);background:var(--maroon-soft);color:var(--maroon);text-decoration:line-through;}
.why-wrong{margin-top:10px;padding:10px 12px;border-radius:10px;background:#fff;border-left:4px solid var(--maroon);font-size:16px;line-height:1.6;}
.why-right{margin-top:10px;font-size:16px;line-height:1.6;}
.ex-en{color:var(--ink-soft);font-size:15px;}
.mistakes{text-align:left;margin:0 auto 24px;max-width:640px;}
.mistakes:empty{display:none;}
.mistakes h3{font-size:20px;margin:0 0 12px;text-align:center;}
.mistake{background:var(--maroon-soft);border-radius:var(--radius-sm);padding:14px 16px;margin-bottom:10px;font-size:16px;}
.mistake .mq{margin:0 0 6px;font-weight:700;font-size:17px;}
body.only-wrong .review-q.right{display:none;}

/* NAV: wrap links on small screens */
.topnav{flex-wrap:wrap;}
.nav-links{flex-wrap:wrap;row-gap:6px;}
@media(max-width:720px){
  .topnav{padding:12px 16px;gap:8px 16px;}
  .nav-links{order:3;flex-basis:100%;gap:6px 16px;}
  .nav-links a{font-size:15px;}
}
.user-row{flex-wrap:wrap;}

/* QUIZ GENERATION PROGRESS */
.gen-progress{width:100%;flex-basis:100%;height:14px;margin:14px 0 6px;background:var(--line);border-radius:999px;overflow:hidden;}
.gen-progress[hidden]{display:none;}
.gen-progress span{display:block;height:100%;width:0;border-radius:999px;background:linear-gradient(90deg,var(--teal),var(--green));transition:width .3s ease;}