:root{
  --bg:#0e1116;
  --bg-soft:#161b22;
  --bg-card:#1b222c;
  --line:#2a323d;
  --text:#e6edf3;
  --muted:#8b96a5;
  --accent:#4db7e0;
  --accent-2:#0c6895;
  --a:#4db7e0;        /* Lettore 1 · blu */
  --a-2:#0c6895;
  --b:#3fb950;        /* Lettore 2 · verde */
  --b-2:#1f7a34;
  --good:#3fb950;
  --bad:#f2545b;
  --warn:#e3b341;
  --radius:16px;
  --shadow:0 8px 30px rgba(0,0,0,.35);
  --page:radial-gradient(1200px 800px at 50% -10%,#17222e 0%,#0e1116 55%);
}
body.theme-light{
  --bg:#eef2f7;
  --bg-soft:#e4eaf1;
  --bg-card:#ffffff;
  --line:#d5dde6;
  --text:#1b2532;
  --muted:#5c6773;
  --a-2:#0c6895;
  --b-2:#1f7a34;
  --shadow:0 8px 30px rgba(20,50,80,.12);
  --page:radial-gradient(1200px 800px at 50% -10%,#dbe8f2 0%,#eef2f7 55%);
}
*{box-sizing:border-box;margin:0;padding:0}
.sr-only{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;
  clip:rect(0,0,0,0);white-space:nowrap;border:0}
html,body{height:100%}
body{
  font-family:'Segoe UI',system-ui,-apple-system,Roboto,sans-serif;
  background:var(--page);color:var(--text);-webkit-font-smoothing:antialiased;
  min-height:100%;display:flex;overflow-x:hidden;transition:background .3s,color .3s;
}
.theme-toggle{position:fixed;top:14px;right:14px;z-index:50;width:44px;height:44px;
  border-radius:50%;background:var(--bg-card);border:1px solid var(--line);color:var(--text);
  font-size:19px;cursor:pointer;box-shadow:var(--shadow);transition:transform .15s,background .3s;
  display:flex;align-items:center;justify-content:center}
.theme-toggle:hover{transform:scale(1.08)}
.theme-toggle:active{transform:scale(.96)}
#app{width:100%;max-width:980px;margin:0 auto;padding:24px 18px 40px;display:flex;flex-direction:column}

/* ---------- schermate ---------- */
.screen{display:none;animation:fade .35s ease}
.screen.active{display:flex;flex-direction:column;flex:1}
@keyframes fade{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* ---------- hero ---------- */
.hero{text-align:center;padding:14px 0 22px}
.logo{font-size:34px;font-weight:800;letter-spacing:1px;
  background:linear-gradient(90deg,var(--a),var(--b));
  -webkit-background-clip:text;background-clip:text;color:transparent}
.logo span{color:var(--muted);-webkit-text-fill-color:var(--muted);font-size:.7em}
.tagline{color:var(--muted);margin-top:6px;font-size:15px}

/* ---------- card ---------- */
.card{background:var(--bg-card);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px;box-shadow:var(--shadow)}
.card h2{font-size:20px;margin-bottom:18px;font-weight:700}
.intro{margin-bottom:16px}
.lead{font-size:15.5px;line-height:1.6;margin-bottom:14px}
.muted{color:var(--muted);font-weight:400}
.field{margin-bottom:16px;display:flex;flex-direction:column;gap:8px}
.field:last-child{margin-bottom:0}
.field label{font-size:14px;font-weight:600}
.hidden{display:none!important}

.banner{padding:12px 14px;border-radius:12px;font-size:13.5px;line-height:1.5;
  border:1px solid var(--line);color:var(--text)}
.banner.note{background:linear-gradient(90deg,rgba(227,179,65,.14),rgba(227,179,65,.05));
  border-color:rgba(227,179,65,.5)}
.banner.note strong{color:var(--warn)}

/* ---------- confronti rapidi ---------- */
.quick{margin-bottom:16px}
.quick-lbl{display:block;font-size:12px;font-weight:700;color:var(--muted);
  text-transform:uppercase;letter-spacing:.6px;margin-bottom:10px}
.quick-lbl .muted{text-transform:none;letter-spacing:0}
.quick-row{display:flex;flex-wrap:wrap;gap:10px}
.chip{background:var(--bg-card);border:1px solid var(--line);color:var(--text);
  padding:10px 16px;border-radius:100px;font-size:14px;font-weight:600;cursor:pointer;
  transition:all .15s;font-family:inherit}
.chip:hover{border-color:var(--accent);color:var(--accent);transform:translateY(-1px)}

/* ---------- lettori ---------- */
.readers{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:18px}
.reader{position:relative;overflow:hidden}
.reader::before{content:"";position:absolute;top:0;left:0;right:0;height:4px}
.reader[data-r="a"]::before{background:linear-gradient(90deg,var(--a-2),var(--a))}
.reader[data-r="b"]::before{background:linear-gradient(90deg,var(--b-2),var(--b))}
.reader-head{display:flex;align-items:center;gap:9px;font-size:17px;font-weight:800;margin-bottom:16px}
.dot{width:13px;height:13px;border-radius:50%;flex:none}
.reader[data-r="a"] .dot,.col[data-r="a"] .dot{background:var(--a)}
.reader[data-r="b"] .dot,.col[data-r="b"] .dot{background:var(--b)}

/* ---------- select ---------- */
.sel-classe{background:var(--bg-soft);border:1px solid var(--line);color:var(--text);
  padding:12px 14px;border-radius:10px;font-size:15px;font-family:inherit;outline:none;
  cursor:pointer;appearance:none;-webkit-appearance:none;
  background-image:url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%238b96a5' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'/%3e%3c/svg%3e");
  background-repeat:no-repeat;background-position:right 12px center;background-size:16px}
.sel-classe:focus{border-color:var(--accent)}

/* ---------- segmented ---------- */
.segmented{display:grid;grid-auto-flow:column;grid-auto-columns:1fr;
  background:var(--bg-soft);border:1px solid var(--line);border-radius:10px;overflow:hidden}
.segmented button{background:transparent;border:none;color:var(--muted);padding:11px 6px;
  font-size:13.5px;font-weight:700;cursor:pointer;font-family:inherit;transition:all .15s}
.segmented button + button{border-left:1px solid var(--line)}
.reader[data-r="a"] .segmented button.active{background:linear-gradient(180deg,rgba(77,183,224,.18),rgba(77,183,224,.05));
  color:var(--text);box-shadow:0 0 0 1px rgba(77,183,224,.4) inset}
.reader[data-r="b"] .segmented button.active{background:linear-gradient(180deg,rgba(63,185,80,.18),rgba(63,185,80,.05));
  color:var(--text);box-shadow:0 0 0 1px rgba(63,185,80,.4) inset}

/* ---------- stepper ---------- */
.stepper{display:flex;align-items:center;background:var(--bg-soft);
  border:1px solid var(--line);border-radius:10px;overflow:hidden}
.stepper button{background:transparent;color:var(--accent);border:none;font-size:22px;
  width:48px;height:48px;cursor:pointer;transition:background .15s;flex:none}
.stepper button:hover{background:rgba(77,183,224,.12)}
.stepper input{background:transparent;border:none;color:var(--text);text-align:center;
  font-size:18px;font-weight:700;width:100%;outline:none;-moz-appearance:textfield}
.stepper input::-webkit-outer-spin-button,.stepper input::-webkit-inner-spin-button{-webkit-appearance:none;margin:0}

/* ---------- lettura velocità ---------- */
.speed-readout{margin-top:14px;padding-top:14px;border-top:1px dashed var(--line);
  font-size:14px;text-align:center}
.sr-val{font-size:26px;font-weight:800;font-variant-numeric:tabular-nums}
.reader[data-r="a"] .sr-val{color:var(--a)}
.reader[data-r="b"] .sr-val{color:var(--b)}

/* ---------- bottoni ---------- */
.btn-primary{width:100%;margin-top:4px;background:linear-gradient(90deg,var(--a-2),var(--a));
  color:#fff;border:none;padding:16px;border-radius:100px;font-size:17px;font-weight:700;
  cursor:pointer;transition:transform .1s,box-shadow .2s;box-shadow:0 6px 18px rgba(12,104,149,.4)}
.btn-primary:hover{box-shadow:0 8px 26px rgba(12,104,149,.55)}
.btn-primary:active{transform:translateY(1px) scale(.995)}
.btn-primary:disabled{opacity:.45;cursor:not-allowed;box-shadow:none}
.btn-ghost{background:transparent;border:1px solid var(--line);color:var(--muted);
  padding:10px 18px;border-radius:100px;font-size:14px;font-weight:600;cursor:pointer;
  transition:all .15s;font-family:inherit}
.btn-ghost:hover{border-color:var(--accent);color:var(--text)}

/* ---------- how / footer ---------- */
.how{margin-top:20px}
.how summary{cursor:pointer;font-weight:600;color:var(--accent);list-style:none}
.how summary::-webkit-details-marker{display:none}
.how summary::before{content:"＋ ";font-weight:700}
.how[open] summary::before{content:"－ "}
.how p{margin:12px 0;font-size:14px;line-height:1.6}
.how ul{margin:10px 0 10px 18px;font-size:14px;line-height:1.9}
.foot{text-align:center;color:var(--muted);font-size:12.5px;margin-top:22px;line-height:1.6}
.foot a{color:var(--accent);text-decoration:none}
.foot a:hover{text-decoration:underline}

/* ===================== CONFRONTO ===================== */
#screen-run.active{justify-content:flex-start}
.run-top{display:flex;align-items:center;justify-content:space-between;gap:12px;
  flex-wrap:wrap;margin-bottom:18px}
.timer{font-size:22px;font-weight:800;font-variant-numeric:tabular-nums;
  background:var(--bg-card);border:1px solid var(--line);border-radius:100px;padding:8px 22px;
  box-shadow:var(--shadow)}
.run-actions{display:flex;gap:10px}

.cols{display:grid;grid-template-columns:1fr 1fr;gap:16px;flex:1;min-height:0}
.col{display:flex;flex-direction:column;min-height:0;background:var(--bg-card);
  border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.col-head{padding:14px 16px;color:#fff}
.col[data-r="a"] .col-head{background:linear-gradient(135deg,var(--a-2),var(--a))}
.col[data-r="b"] .col-head{background:linear-gradient(135deg,var(--b-2),var(--b))}
.col-name{display:flex;align-items:center;gap:8px;font-size:18px;font-weight:800}
.col-name .dot{background:#fff!important;opacity:.9}
.col-status{margin-left:auto;font-size:13px;font-weight:700;opacity:.95}
.col-meta{font-size:13.5px;margin-top:6px;opacity:.95;line-height:1.4}
.col-speed{font-size:13px;margin-top:2px;opacity:.85;font-weight:600}

.prog{height:8px;background:var(--bg-soft);margin:0}
.prog-bar{height:100%;width:0;transition:width .12s linear}
.col[data-r="a"] .prog-bar{background:linear-gradient(90deg,var(--a-2),var(--a))}
.col[data-r="b"] .prog-bar{background:linear-gradient(90deg,var(--b-2),var(--b))}
.prog-pct{font-size:12px;font-weight:700;color:var(--muted);text-align:right;padding:4px 12px 0;
  font-variant-numeric:tabular-nums}

.reading{flex:1;min-height:180px;overflow-y:auto;padding:16px 18px;
  font-size:clamp(17px,2.4vw,21px);line-height:2;letter-spacing:.2px}
.reading::-webkit-scrollbar{width:8px}
.reading::-webkit-scrollbar-thumb{background:var(--line);border-radius:4px}
.syl{border-radius:4px;transition:background .25s,color .25s}
.col[data-r="a"] .syl.cur{background:var(--a);color:#fff}
.col[data-r="b"] .syl.cur{background:var(--b);color:#fff}
.col-head.fin .col-status::before{content:""}

/* ---------- modale risultati ---------- */
.modal-overlay{position:fixed;inset:0;z-index:100;display:flex;align-items:center;justify-content:center;
  padding:20px;background:rgba(4,8,12,.62);opacity:0;transition:opacity .18s}
.modal-overlay.show{opacity:1}
.modal-box{width:100%;max-width:460px;background:var(--bg-card);border:1px solid var(--line);
  border-radius:16px;padding:24px;box-shadow:var(--shadow);transform:translateY(8px);transition:transform .18s}
.modal-overlay.show .modal-box{transform:none}
.modal-title{font-size:21px;font-weight:800;margin-bottom:16px;text-align:center}
.verdict{text-align:center;font-size:15px;line-height:1.6;margin-bottom:20px}
.verdict .big{display:block;font-size:40px;font-weight:800;line-height:1.1;margin:6px 0;
  background:linear-gradient(90deg,var(--a),var(--b));-webkit-background-clip:text;background-clip:text;color:transparent}
.res-rows{display:flex;flex-direction:column;gap:10px;margin-bottom:22px}
.res-row{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:12px;
  background:var(--bg-soft);border:1px solid var(--line);border-radius:12px;padding:12px 14px}
.res-row .dot{width:12px;height:12px;border-radius:50%}
.res-row[data-r="a"] .dot{background:var(--a)}
.res-row[data-r="b"] .dot{background:var(--b)}
.res-name{font-weight:700;font-size:14px}
.res-sub{font-size:12px;color:var(--muted);margin-top:2px}
.res-val{font-weight:800;font-size:20px;font-variant-numeric:tabular-nums;text-align:right}
.res-row[data-r="a"] .res-val{color:var(--a)}
.res-row[data-r="b"] .res-val{color:var(--b)}
.modal-actions{display:flex;gap:12px}
.modal-actions .btn-primary{margin-top:0;flex:1}
.modal-actions .btn-ghost{flex:none}

/* ---------- responsive ---------- */
@media (max-width:640px){
  .readers{grid-template-columns:1fr}
  .cols{grid-template-columns:1fr;overflow-y:auto}
  .col{min-height:260px}
  .reading{min-height:120px;max-height:34vh}
  .logo{font-size:28px}
  .card{padding:18px}
  .run-top{justify-content:center}
  .timer{order:-1;flex-basis:100%;text-align:center}
}