:root {
      --brand:#0891b2; --brand-dark:#0e7490; --brand-light:#e0f2fe;
      --success:#10b981; --danger:#ef4444; --warning:#f59e0b;
      --text:#0f172a; --text-muted:#64748b; --bg:#f1f5f9;
      --surface:#ffffff; --border:#e2e8f0;
      --radius:10px; --radius-lg:16px;
      --shadow:0 1px 3px rgba(0,0,0,.06),0 4px 16px rgba(0,0,0,.04);
    }
    body.dark-mode {
      --text:#e2e8f0; --text-muted:#94a3b8; --bg:#0f172a;
      --surface:#1e293b; --border:#334155; --brand-light:#164e63;
    }
    *,*::before,*::after{box-sizing:border-box;margin:0;padding:0;}
    html{scroll-behavior:smooth;}
    body{font-family:'DM Sans','Noto Sans TC',sans-serif;font-size:14px;line-height:1.6;
      background:var(--bg);color:var(--text);transition:background .2s,color .2s;min-height:100vh;}

    /* Header */
    .page-header{background:var(--surface);border-bottom:1px solid var(--border);
      padding:12px 24px;display:flex;align-items:center;justify-content:space-between;
      position:sticky;top:0;z-index:200;}
    .brand{display:flex;align-items:center;gap:10px;}
    .brand img{height:32px;}
    .brand-name{font-size:15px;font-weight:700;color:var(--brand);}
    .brand-sub{font-size:11px;color:var(--text-muted);}
    .logo-dark{display:none;}.logo-light{display:block;}
    body.dark-mode .logo-dark{display:block;}body.dark-mode .logo-light{display:none;}
    .theme-toggle{background:none;border:1px solid var(--border);border-radius:8px;
      padding:6px 10px;color:var(--text-muted);cursor:pointer;font-size:14px;transition:all .15s;}
    .theme-toggle:hover{border-color:var(--brand);color:var(--brand);}

    /* Layout */
    .page-main{max-width:860px;margin:0 auto;padding:28px 16px 80px;}

    /* Progress */
    .top-progress{display:flex;align-items:center;margin-bottom:28px;}
    .tp-step{display:flex;flex-direction:column;align-items:center;flex:1;position:relative;}
    .tp-step:not(:last-child)::after{content:'';position:absolute;top:14px;left:calc(50% + 14px);
      width:calc(100% - 28px);height:2px;background:var(--border);transition:background .4s;z-index:0;}
    .tp-step.done:not(:last-child)::after{background:var(--success);}
    .tp-node{width:28px;height:28px;border-radius:50%;background:var(--surface);
      border:2px solid var(--border);display:flex;align-items:center;justify-content:center;
      font-size:11px;font-weight:700;color:var(--text-muted);position:relative;z-index:1;transition:all .3s;}
    .tp-step.active .tp-node{border-color:var(--brand);background:var(--brand);color:#fff;}
    .tp-step.done .tp-node{border-color:var(--success);background:var(--success);color:#fff;}
    .tp-label{font-size:10px;font-weight:600;color:var(--text-muted);margin-top:5px;
      text-align:center;text-transform:uppercase;letter-spacing:.3px;transition:color .3s;}
    .tp-step.active .tp-label{color:var(--brand);}
    .tp-step.done .tp-label{color:var(--success);}

    /* Cards */
    .form-card{background:var(--surface);border:1px solid var(--border);
      border-radius:var(--radius-lg);padding:24px;box-shadow:var(--shadow);margin-bottom:18px;}
    .card-title{font-size:15px;font-weight:700;color:var(--brand);margin-bottom:18px;
      display:flex;align-items:center;gap:8px;padding-bottom:12px;border-bottom:1px solid var(--border);}
    .section-label{font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.8px;
      color:var(--brand);border-left:3px solid var(--brand);padding-left:8px;margin:20px 0 14px;}
    .q-num{display:inline-flex;align-items:center;justify-content:center;width:22px;height:22px;
      border-radius:50%;background:var(--brand-light);color:var(--brand);
      font-size:10px;font-weight:700;flex-shrink:0;margin-right:6px;}
    body.dark-mode .q-num{background:rgba(8,145,178,.25);}

    /* Fields - IMPROVED */
    .field-row{margin-bottom:18px;}
    .field-row label{
      display:block;
      font-size:12px;
      font-weight:600;
      color:var(--text-muted);
      margin-bottom:8px;
      text-transform:uppercase;
      letter-spacing:.3px;
      line-height:1.5;
    }
    .field-row label .req{color:var(--danger);margin-left:3px;}
    .field-row input[type=text],
    .field-row input[type=email],
    .field-row input[type=tel],
    .field-row input[type=number],
    .field-row select,
    .field-row textarea{
      width:100%;
      padding:10px 14px;
      font-size:14px;
      background:var(--bg);
      border:1.5px solid var(--border);
      border-radius:var(--radius);
      color:var(--text);
      outline:none;
      transition:border-color .15s,box-shadow .15s;
      font-family:inherit;
      line-height:1.5;
    }
    .field-row input:focus,
    .field-row select:focus,
    .field-row textarea:focus{
      border-color:var(--brand);
      box-shadow:0 0 0 3px rgba(8,145,178,.12);
    }
    .field-row input[readonly]{
      background:var(--brand-light);
      color:var(--brand);
      font-weight:700;
      cursor:default;
      border-color:transparent;
    }
    body.dark-mode .field-row input[readonly]{background:rgba(8,145,178,.15);}
    .field-row textarea{resize:vertical;min-height:80px;}
    
    /* Grid layouts - IMPROVED */
    .col-2{
      display:grid;
      grid-template-columns:1fr 1fr;
      gap:18px;
      align-items:start;
    }
    .col-3{
      display:grid;
      grid-template-columns:1fr 1fr 1fr;
      gap:14px;
      align-items:start;
    }
    
    /* Make sure nested field-rows in grid don't have bottom margin conflict */
    .col-2 .field-row,
    .col-3 .field-row {
      margin-bottom:0;
    }
    
    @media(max-width:640px){
      .col-2,.col-3{grid-template-columns:1fr;}
      .col-2{gap:16px;}
      .col-3{gap:16px;}
      .form-card{padding:16px;}
    }

    /* Autofill strip */
    .autofill-strip{background:var(--brand-light);border:1px solid rgba(8,145,178,.3);
      border-radius:var(--radius);padding:10px 14px;display:flex;align-items:center;
      gap:10px;margin-bottom:16px;font-size:12px;}
    .autofill-strip i{color:var(--brand);}
    body.dark-mode .autofill-strip{background:rgba(8,145,178,.15);}

    /* Radio pills */
    .radio-group{display:flex;flex-wrap:wrap;gap:8px;margin-top:4px;}
    .radio-pill{display:flex;align-items:center;gap:5px;padding:7px 14px;
      border:1.5px solid var(--border);border-radius:20px;font-size:12px;font-weight:500;
      cursor:pointer;transition:all .15s;user-select:none;}
    .radio-pill input{display:none;}
    .radio-pill:has(input:checked){border-color:var(--brand);background:var(--brand-light);
      color:var(--brand);font-weight:700;}
    body.dark-mode .radio-pill:has(input:checked){background:rgba(8,145,178,.2);}

    /* Consent pills */
    .consent-group{display:flex;gap:12px;margin-top:6px;}
    .consent-pill{flex:1;display:flex;align-items:center;justify-content:center;gap:8px;
      padding:12px 16px;border:2px solid var(--border);border-radius:12px;
      font-size:13px;font-weight:600;cursor:pointer;transition:all .15s;user-select:none;}
    .consent-pill input{display:none;}
    .consent-pill.agree:has(input:checked){border-color:var(--success);background:rgba(16,185,129,.08);color:#059669;}
    .consent-pill.disagree:has(input:checked){border-color:var(--danger);background:rgba(239,68,68,.08);color:var(--danger);}
    .consent-pill i{font-size:16px;}

    /* Scale dots */
    .scale-row{display:flex;align-items:center;gap:14px;margin-top:4px;}
    .scale-dots{display:flex;gap:8px;}
    .scale-dot{width:36px;height:36px;border-radius:50%;border:2px solid var(--border);
      background:var(--bg);display:flex;align-items:center;justify-content:center;
      font-size:13px;font-weight:700;cursor:pointer;transition:all .15s;color:var(--text-muted);}
    .scale-dot:hover{border-color:var(--brand);color:var(--brand);}
    .scale-dot.on{border-color:var(--brand);background:var(--brand);color:#fff;}
    .scale-label{font-size:11px;color:var(--text-muted);}

    /* Language grid */
    .lang-grid{width:100%;border-collapse:collapse;margin-top:4px;}
    .lang-grid th{font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.4px;
      color:var(--text-muted);padding:8px 12px;background:var(--bg);
      border:1px solid var(--border);text-align:center;}
    .lang-grid td{padding:8px 12px;border:1px solid var(--border);text-align:center;font-size:13px;}
    .lang-grid td:first-child{text-align:left;font-weight:600;}
    .lang-cell{display:flex;justify-content:center;gap:6px;}
    .lang-radio{display:none;}
    .lang-lbl{padding:4px 10px;border-radius:14px;border:1.5px solid var(--border);
      font-size:11px;font-weight:600;cursor:pointer;transition:all .12s;color:var(--text-muted);}
    .lang-radio:checked + .lang-lbl{border-color:var(--brand);background:var(--brand);color:#fff;}
    @media(max-width:640px){
      .lang-grid,.lang-grid thead,.lang-grid tbody,.lang-grid th,.lang-grid td,.lang-grid tr{display:block;}
      .lang-grid thead{display:none;}
      .lang-grid tr{margin-bottom:12px;border:1px solid var(--border);border-radius:8px;overflow:hidden;}
      .lang-grid td{display:flex;justify-content:space-between;align-items:center;}
      .lang-grid td:first-child{background:var(--bg);font-weight:700;}
      .lang-grid td::before{content:attr(data-label);font-size:11px;color:var(--text-muted);font-weight:600;}
    }

    /* Verify screen */
    #screen-verify{max-width:480px;margin:0 auto;}
    .verify-hero{text-align:center;margin-bottom:28px;}
    .verify-icon-wrap{width:64px;height:64px;border-radius:50%;background:var(--brand-light);
      display:flex;align-items:center;justify-content:center;margin:0 auto 16px;
      animation:pulseRing 2s ease infinite;}
    .verify-icon-wrap i{font-size:28px;color:var(--brand);}
    @keyframes pulseRing{0%,100%{box-shadow:0 0 0 0 rgba(8,145,178,.25);}50%{box-shadow:0 0 0 12px rgba(8,145,178,0);}}
    .verify-hero h2{font-size:20px;font-weight:700;margin-bottom:6px;}
    .verify-hero .sub{font-size:13px;color:var(--text-muted);}

    /* Captcha */
    .cap-divider{display:flex;align-items:center;gap:8px;font-size:10px;font-weight:700;
      text-transform:uppercase;letter-spacing:.6px;color:var(--text-muted);margin:16px 0 10px;}
    .cap-divider::before,.cap-divider::after{content:'';flex:1;height:1px;background:var(--border);}
    .cap-tabs{display:flex;gap:4px;margin-bottom:10px;}
    .cap-tab{flex:1;padding:6px 0;font-size:11px;font-weight:700;text-transform:uppercase;
      letter-spacing:.4px;background:var(--bg);border:1px solid var(--border);
      border-radius:8px;cursor:pointer;color:var(--text-muted);transition:all .15s;}
    .cap-tab.on{background:var(--brand);border-color:var(--brand);color:#fff;}
    .cap-panel{display:none;}.cap-panel.on{display:block;}
    canvas#capCanvas{border-radius:8px;border:1px solid var(--border);cursor:pointer;flex-shrink:0;}
    .cap-timer-row{position:relative;width:28px;height:28px;
      display:flex;align-items:center;justify-content:center;flex-shrink:0;}
    .ring-svg{position:absolute;width:28px;height:28px;transform:rotate(-90deg);}
    .ring-bg{fill:none;stroke:var(--border);stroke-width:2.5;}
    .ring-fill{fill:none;stroke:var(--brand);stroke-width:2.5;stroke-dasharray:66;
      stroke-dashoffset:0;stroke-linecap:round;transition:stroke-dashoffset 1s linear,stroke .5s;}
    .cap-timer-row span{position:relative;z-index:1;font-size:8px;font-weight:700;color:var(--text-muted);}
    .ref-btn{background:none;border:1px solid var(--border);border-radius:6px;padding:3px 8px;
      font-size:10px;color:var(--text-muted);cursor:pointer;display:flex;align-items:center;
      gap:3px;transition:all .15s;white-space:nowrap;}
    .ref-btn:hover{border-color:var(--brand);color:var(--brand);}
    .cap-ok,.cap-err{display:none;align-items:center;gap:6px;font-size:12px;font-weight:600;
      padding:6px 10px;border-radius:7px;margin-top:6px;}
    .cap-ok.on{display:flex;background:rgba(16,185,129,.1);color:#059669;}
    .cap-err.on{display:flex;background:rgba(239,68,68,.08);color:var(--danger);}
    .ok-circle{width:16px;height:16px;border-radius:50%;background:var(--success);
      display:flex;align-items:center;justify-content:center;flex-shrink:0;}
    .math-disp{background:var(--bg);border:1px solid var(--border);border-radius:8px;
      padding:10px 16px;font-size:18px;font-weight:700;text-align:center;color:var(--text);
      letter-spacing:2px;font-family:'Courier New',monospace;}
    .emoji-grid{display:grid;grid-template-columns:repeat(7,1fr);gap:5px;margin-bottom:7px;}
    .grid-cell{aspect-ratio:1;font-size:clamp(16px,4vw,24px);display:flex;align-items:center;
      justify-content:center;border-radius:6px;cursor:pointer;border:2px solid transparent;
      background:rgba(8,145,178,.06);transition:all .12s;user-select:none;}
    .grid-cell:hover{background:rgba(8,145,178,.14);transform:scale(1.06);}
    .grid-cell.sel{border-color:var(--brand);background:rgba(8,145,178,.22);}
    .grid-prompt{font-size:12px;font-weight:600;color:var(--text-muted);margin-bottom:8px;}
    .cc-counter{font-size:10px;color:var(--text-muted);font-family:monospace;}

    /* Token input */
    .token-input{text-align:center;font-size:22px;font-weight:800;letter-spacing:6px;
      font-family:'Courier New',monospace;padding:12px;border-radius:var(--radius);
      border:2px solid var(--border);background:var(--bg);color:var(--text);
      width:100%;outline:none;text-transform:uppercase;transition:border-color .15s,box-shadow .15s;}
    .token-input:focus{border-color:var(--brand);box-shadow:0 0 0 3px rgba(8,145,178,.15);}
    .token-input.err{border-color:var(--danger);box-shadow:0 0 0 3px rgba(239,68,68,.12);}

    /* Buttons */
    .btn-primary{background:var(--brand);color:#fff;border:none;border-radius:var(--radius);
      padding:11px 24px;font-size:14px;font-weight:700;cursor:pointer;width:100%;
      transition:background .15s,transform .1s;font-family:inherit;}
    .btn-primary:hover{background:var(--brand-dark);}
    .btn-primary:disabled{background:var(--text-muted);cursor:not-allowed;}
    .btn-success{background:var(--success);color:#fff;border:none;border-radius:var(--radius);
      padding:12px 28px;font-size:14px;font-weight:700;cursor:pointer;transition:all .15s;font-family:inherit;}
    .btn-success:hover{filter:brightness(1.08);}
    .btn-success:disabled{opacity:.6;cursor:not-allowed;}
    .btn-nav{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);
      padding:10px 20px;font-size:13px;font-weight:600;cursor:pointer;color:var(--text);
      transition:all .15s;display:flex;align-items:center;gap:6px;font-family:inherit;}
    .btn-nav:hover{border-color:var(--brand);color:var(--brand);}
    .btn-nav.primary{background:var(--brand);color:#fff;border-color:var(--brand);}
    .btn-nav.primary:hover{background:var(--brand-dark);}

    /* Error */
    .err-msg{font-size:12px;color:var(--danger);margin-top:5px;display:none;}
    .err-msg.on{display:block;}

    /* Verified badge */
    .verified-strip{background:rgba(16,185,129,.08);border:1px solid rgba(16,185,129,.3);
      border-radius:var(--radius);padding:10px 14px;display:flex;align-items:center;
      gap:10px;margin-bottom:20px;font-size:12px;}
    .verified-strip .vs-icon{color:var(--success);font-size:16px;}
    .verified-strip .vs-text{font-weight:600;color:var(--success);}
    .verified-strip .vs-code{margin-left:auto;font-family:monospace;font-size:12px;
      background:rgba(16,185,129,.12);padding:2px 8px;border-radius:5px;
      color:var(--success);font-weight:700;}

    /* Step nav */
    .form-nav{display:flex;justify-content:space-between;align-items:center;margin-top:28px;gap:12px;}

    /* Visibility */
    .app-screen{display:none;}.app-screen.active{display:block;}
    .form-step{display:none;}.form-step.active{display:block;}
    .step-header{margin-bottom:22px;}
    .step-header h3{font-size:18px;font-weight:700;margin-bottom:4px;}
    .step-header p{font-size:13px;color:var(--text-muted);}

    /* Privacy / consent text boxes */
    .consent-text-box{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);
      padding:14px;font-size:12px;line-height:1.8;color:var(--text-muted);
      max-height:180px;overflow-y:auto;margin-bottom:14px;}

    /* Challenge options */
    .challenge-opts{display:flex;flex-direction:column;gap:10px;margin-top:4px;}
    .challenge-opt{border:1.5px solid var(--border);border-radius:var(--radius);
      padding:12px 14px;cursor:pointer;transition:all .15s;font-size:13px;user-select:none;}
    .challenge-opt input{display:none;}
    .challenge-opt:has(input:checked){border-color:var(--brand);background:var(--brand-light);}
    body.dark-mode .challenge-opt:has(input:checked){background:rgba(8,145,178,.15);}
    .challenge-opt .opt-title{font-weight:700;margin-bottom:3px;color:var(--brand);}
    .challenge-opt .opt-body{font-size:12px;color:var(--text-muted);}

    /* Success */
    #screen-success{text-align:center;padding:60px 24px;}
    .success-anim{width:80px;height:80px;border-radius:50%;background:rgba(16,185,129,.12);
      border:2px solid var(--success);display:flex;align-items:center;justify-content:center;
      margin:0 auto 24px;font-size:36px;}
    #screen-success h2{font-size:24px;font-weight:800;margin-bottom:10px;}
    #screen-success p{color:var(--text-muted);font-size:14px;line-height:1.8;}

    /* Shake */
    @keyframes shake{0%,100%{transform:translateX(0);}20%{transform:translateX(-6px);}
      40%{transform:translateX(6px);}60%{transform:translateX(-4px);}80%{transform:translateX(3px);}}
    .shake{animation:shake .35s ease;}