:root{
  --navy:#0A2540; --navy-2:#0F2D4C; --navy-3:#143759;
  --teal:#0EA5A4; --teal-dark:#0F766E; --teal-darker:#115E59;
  --teal-hover:#0B9594; --teal-soft:#CFFAF4; --teal-tint:#E6FBF7;
  --coral:#F97066; --coral-soft:#FEE4E2;
  --amber:#FCD34D; --amber-soft:#FEF3C7;
  --ink:#0A2540; --slate:#475569; --muted:#64748B;
  --line:#E2E8F0; --line-2:#EEF2F6;
  --bg:#FFFFFF; --bg-soft:#F6FBFA;
  --red:#DC2626; --green:#16A34A;
  --radius:14px; --radius-lg:20px;
  --shadow-sm:0 2px 6px rgba(10,37,64,.07);
  --shadow-md:0 10px 32px rgba(10,37,64,.10);
  --font-display:'Bricolage Grotesque','Inter Tight',system-ui,-apple-system,sans-serif;
  --font-body:'Inter Tight','Inter',system-ui,-apple-system,'Segoe UI',sans-serif;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
[hidden]{display:none !important}
html{-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
body{font-family:var(--font-body);background:var(--bg-soft);color:var(--ink);line-height:1.6;font-size:17px;min-height:100vh}
h1,h2,h3,h4{font-family:var(--font-display);line-height:1.15;letter-spacing:-.022em;font-weight:700;color:var(--navy)}
a{color:inherit;text-decoration:none}
button{font:inherit;cursor:pointer;background:none;border:none;color:inherit}
:focus-visible{outline:3px solid var(--teal);outline-offset:2px;border-radius:8px}

.container{width:100%;max-width:980px;margin:0 auto;padding:0 24px}

.nav{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);backdrop-filter:saturate(180%) blur(12px);border-bottom:1px solid var(--line)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:64px;gap:24px}
.logo{font-family:var(--font-display);font-weight:800;font-size:22px;letter-spacing:-.025em;color:var(--navy)}
.logo-ai{color:var(--teal-dark)}
.nav-back{font-weight:600;font-size:14px;color:var(--slate)}
.nav-back:hover{color:var(--teal-dark)}

.main{padding:48px 24px 80px}

.hero{text-align:center;margin-bottom:40px}
.hero h1{font-size:clamp(32px,4vw,44px);margin-bottom:14px}
.hero .lede{color:var(--slate);font-size:17px;max-width:640px;margin:0 auto}

/* Buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;font-family:var(--font-body);font-weight:700;font-size:16px;border-radius:12px;padding:14px 22px;transition:transform .2s,background .2s,box-shadow .2s;white-space:nowrap;letter-spacing:-.005em}
.btn-primary{background:var(--teal);color:#063A39;box-shadow:0 4px 14px rgba(14,165,164,.34),inset 0 1px 0 rgba(255,255,255,.25)}
.btn-primary:hover:not(:disabled){background:var(--teal-hover);transform:translateY(-2px);box-shadow:0 10px 28px rgba(14,165,164,.48)}
.btn-primary:disabled{opacity:.45;cursor:not-allowed}
.btn-outline{background:#fff;color:var(--ink);border:1.5px solid var(--line)}
.btn-outline:hover{border-color:var(--teal);color:var(--teal-dark)}

/* Upload card */
.upload-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);box-shadow:var(--shadow-sm);padding:28px;margin-bottom:28px}
.dropzone{display:block;border:2px dashed var(--teal);background:var(--teal-tint);border-radius:var(--radius);padding:48px 24px;text-align:center;cursor:pointer;transition:background .2s,border-color .2s,transform .15s}
.dropzone:hover,.dropzone.dragover{background:var(--teal-soft);border-color:var(--teal-dark);transform:translateY(-1px)}
.dropzone-icon{font-size:42px;margin-bottom:10px}
.dropzone-title{font-family:var(--font-display);font-weight:700;font-size:20px;color:var(--navy);margin-bottom:4px}
.dropzone-sub{color:var(--slate);font-size:14px}
.dropzone-filename{margin-top:14px;font-weight:600;color:var(--teal-darker);font-size:15px;background:#fff;display:inline-block;padding:8px 14px;border-radius:8px;border:1px solid var(--teal)}
.upload-actions{display:flex;gap:12px;margin-top:20px;justify-content:flex-end}

/* Status */
.status{display:flex;align-items:center;gap:14px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:18px 22px;margin-bottom:24px}
.spinner{width:22px;height:22px;border:3px solid var(--teal-soft);border-top-color:var(--teal-dark);border-radius:50%;animation:spin .9s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.status-text{color:var(--slate);font-weight:500}

/* Results */
.results{background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);box-shadow:var(--shadow-sm);padding:32px;margin-bottom:24px}
.results-header{display:flex;justify-content:space-between;align-items:flex-start;gap:20px;flex-wrap:wrap;margin-bottom:28px;padding-bottom:20px;border-bottom:1px solid var(--line-2)}
.results-header h2{font-size:28px;margin-bottom:6px}
.results-sub{color:var(--slate);font-size:14px}
.results-overcharge{text-align:right}
.oc-label{font-size:12px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted);font-weight:600;margin-bottom:4px}
.oc-amt{font-family:var(--font-display);font-weight:800;font-size:32px;color:var(--red);letter-spacing:-.02em}
.oc-amt.zero{color:var(--green)}

.section-h{font-size:18px;margin:24px 0 14px;color:var(--navy)}

/* Findings */
.findings{display:flex;flex-direction:column;gap:12px}
.finding{display:flex;gap:14px;padding:16px;border-radius:var(--radius);border:1px solid var(--line);background:#fff;transition:box-shadow .15s}
.finding:hover{box-shadow:var(--shadow-sm)}
.finding-severity{flex-shrink:0;width:8px;border-radius:6px;background:var(--muted)}
.finding.sev-high .finding-severity{background:var(--red)}
.finding.sev-medium .finding-severity{background:var(--amber)}
.finding.sev-low .finding-severity{background:var(--teal)}
.finding-body{flex:1;min-width:0}
.finding-title{font-weight:700;color:var(--navy);font-size:16px;margin-bottom:4px;display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.finding-badge{font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.06em;padding:3px 8px;border-radius:6px;background:var(--line-2);color:var(--slate)}
.finding.sev-high .finding-badge{background:#FEE2E2;color:#991B1B}
.finding.sev-medium .finding-badge{background:var(--amber-soft);color:#92400E}
.finding.sev-low .finding-badge{background:var(--teal-soft);color:var(--teal-darker)}
.finding-detail{color:var(--slate);font-size:14px;line-height:1.55;margin-bottom:8px}
.finding-amount{font-weight:700;color:var(--red);font-size:15px}
.finding-amount.zero{color:var(--slate)}
.finding-codes{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:12px;color:var(--muted);margin-top:6px}
.findings-empty{padding:24px;text-align:center;color:var(--green);background:#F0FDF4;border:1px solid #BBF7D0;border-radius:var(--radius);font-weight:600}

/* Line items table */
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius)}
.lineitems{width:100%;border-collapse:collapse;font-size:14px}
.lineitems thead{background:var(--bg-soft)}
.lineitems th{text-align:left;padding:12px 14px;font-weight:700;color:var(--navy);font-size:13px;text-transform:uppercase;letter-spacing:.04em;border-bottom:1px solid var(--line)}
.lineitems td{padding:12px 14px;border-bottom:1px solid var(--line-2);color:var(--ink)}
.lineitems tr:last-child td{border-bottom:none}
.lineitems .num{text-align:right;font-variant-numeric:tabular-nums}
.lineitems .code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-weight:600;color:var(--teal-darker)}

.raw-json{margin-top:24px;font-size:13px}
.raw-json summary{cursor:pointer;color:var(--slate);font-weight:600;padding:8px 0;user-select:none}
.raw-json summary:hover{color:var(--teal-dark)}
.raw-json pre{background:var(--navy);color:#E2E8F0;padding:18px;border-radius:var(--radius);overflow-x:auto;font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:12px;line-height:1.5;margin-top:10px;max-height:400px}

/* Error */
.error{background:#FEF2F2;border:1px solid #FECACA;border-radius:var(--radius);padding:18px 22px;margin-bottom:24px}
.error-title{font-weight:700;color:#991B1B;margin-bottom:4px}
.error-msg{color:#7F1D1D;font-size:14px}

.footer{text-align:center;padding:32px 0 8px;color:var(--muted);font-size:13px;line-height:1.6}

@media (max-width:640px){
  .main{padding:32px 16px 60px}
  .upload-card{padding:20px}
  .results{padding:22px}
  .dropzone{padding:36px 16px}
  .results-header{flex-direction:column;align-items:flex-start}
  .results-overcharge{text-align:left}
}

/* Extended nav */
.nav-links{display:flex;align-items:center;gap:18px}
.nav-user{font-size:14px;color:var(--slate);font-weight:600}
.nav-link{font-weight:600;font-size:14px;color:var(--slate);transition:color .15s}
.nav-link:hover{color:var(--teal-dark)}
.nav-link-btn{padding:0;background:none;border:none;cursor:pointer}

/* Auth card */
.auth-card{max-width:460px;margin:24px auto 0;background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);box-shadow:var(--shadow-sm);padding:32px}
.auth-tabs{display:flex;gap:4px;background:var(--bg-soft);border-radius:10px;padding:4px;margin-bottom:24px}
.auth-tab{flex:1;padding:10px 8px;border-radius:8px;font-size:13px;font-weight:600;color:var(--slate);text-align:center;transition:background .15s,color .15s}
.auth-tab:hover{color:var(--navy)}
.auth-tab.is-active{background:#fff;color:var(--navy);box-shadow:var(--shadow-sm)}
.auth-form{display:flex;flex-direction:column;gap:16px}
.auth-form h2{font-size:22px;margin-bottom:4px}
.auth-field{display:flex;flex-direction:column;gap:6px}
.auth-field>span{font-size:13px;font-weight:600;color:var(--navy)}
.auth-field input{font:inherit;font-size:15px;padding:12px 14px;border:1.5px solid var(--line);border-radius:10px;background:#fff;color:var(--ink);transition:border-color .15s,box-shadow .15s}
.auth-field input:focus{outline:none;border-color:var(--teal);box-shadow:0 0 0 3px rgba(14,165,164,.15)}
.auth-hint{color:var(--muted);font-size:12px}
.auth-sub{color:var(--slate);font-size:14px;margin-bottom:4px}
.auth-error{margin-top:16px;padding:12px 14px;background:#FEF2F2;border:1px solid #FECACA;color:#991B1B;border-radius:10px;font-size:14px;font-weight:500}

/* History */
.history-table tbody tr{cursor:pointer;transition:background .12s}
.history-row:hover{background:var(--teal-tint)}
.empty{padding:48px 24px;text-align:center;color:var(--slate);background:#fff;border:1px dashed var(--line);border-radius:var(--radius);font-size:15px}
.empty a{color:var(--teal-dark);font-weight:600}

@media (max-width:640px){
  .nav-links{gap:10px}
  .nav-user{display:none}
  .auth-card{padding:22px}
  .auth-tab{font-size:12px;padding:8px 4px}
}

/* --- Dispute letter download CTA --- */
.results-actions{
  display:flex;align-items:center;gap:14px;flex-wrap:wrap;
  margin:8px 0 24px 0;padding:16px 18px;
  background:linear-gradient(135deg,rgba(14,165,164,.07),rgba(14,165,164,.03));
  border:1px solid rgba(14,165,164,.18);border-radius:12px;
}
.results-actions .btn{flex-shrink:0}
.results-actions-hint{
  color:#475569;font-size:.92rem;line-height:1.45;flex:1;min-width:220px;
}

/* --- Settings page --- */
.settings-card .settings-sub{color:#475569;font-size:.95rem;line-height:1.5;margin:.5rem 0 1.2rem 0}
.settings-flash{margin-top:1rem;padding:.7rem 1rem;border-radius:8px;background:rgba(16,185,129,.1);color:#065f46;border:1px solid rgba(16,185,129,.25);font-size:.92rem}
.auth-field textarea{
  font:inherit;padding:.7rem .9rem;border:1px solid rgba(0,0,0,.12);border-radius:8px;
  background:rgba(255,255,255,.9);width:100%;box-sizing:border-box;resize:vertical;
}
.auth-field textarea:focus{outline:none;border-color:var(--teal);box-shadow:0 0 0 3px rgba(14,165,164,.15)}
.auth-field input:disabled{background:rgba(0,0,0,.04);color:#94a3b8;cursor:not-allowed}