.isdn-hero{padding:48px 0 40px}.isdn-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:46px;align-items:center}
.isdn-hero h1{font-size:clamp(3.3rem,5.7vw,5.8rem);line-height:.9;letter-spacing:-.055em;margin:12px 0 20px}.isdn-hero .lead{font-size:1.17rem;line-height:1.65;color:#d8dde7}
.wtf{margin:20px 0;padding:15px 17px;border-left:3px solid var(--cyan);background:rgba(86,215,255,.055);border-radius:0 12px 12px 0;font-weight:850}
.ntba{width:min(100%,450px);justify-self:end;background:#e8e5db;border-radius:24px;padding:30px 24px;color:#222;box-shadow:var(--shadow);border:1px solid #bbb}.ntba-logo{font:900 1rem Arial;color:#555}.ntba-box{margin-top:16px;background:#f5f2e8;border:2px solid #aaa;border-radius:7px;padding:28px 18px;box-shadow:inset 0 0 20px #ccc}.ntba-box strong{font:900 1.5rem Arial}.ntba-led{display:flex;gap:7px;align-items:center;margin-top:25px;font:12px Arial}.ntba-led:before{content:"";width:9px;height:9px;border-radius:50%;background:#45bd55;box-shadow:0 0 7px #45bd55}
.fact-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:11px;margin-top:28px}.fact{background:var(--panel);border:1px solid var(--line);border-radius:17px;padding:17px}.fact strong{display:block;color:var(--gold);font-size:1.22rem}.fact small{color:var(--muted)}
.channel-grid{display:grid;grid-template-columns:1.08fr .92fr;gap:18px}.panel{background:var(--panel);border:1px solid var(--line);border-radius:24px;padding:24px}
.channels{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:20px 0}.channel{padding:22px;border:1px solid var(--line);border-radius:18px;background:#101620;text-align:center}.channel.active{outline:2px solid var(--cyan);background:#10232b}.channel strong{display:block;font-size:2rem;color:var(--gold)}.channel button{margin-top:12px}
.speed{font-size:clamp(3rem,7vw,5rem);font-weight:950;color:var(--gold);line-height:1}.status{padding:14px;border-radius:12px;background:#101720;margin-top:15px;font-weight:850}
.phone-sim{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:20px}.phone-state{border:1px solid var(--line);border-radius:16px;padding:18px;text-align:center}.phone-state .emoji{font-size:3rem}.phone-state.ok{background:#10251a}.phone-state.off{background:#2a1717}
.range{width:100%;accent-color:var(--orange);margin:18px 0}.bigtime{font-size:clamp(2.7rem,6vw,4.7rem);font-weight:950;color:var(--gold);line-height:1}
.compare{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.compare>div{background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:22px}.compare strong{font-size:1.4rem}
.quiz-options{display:grid;grid-template-columns:repeat(2,1fr);gap:9px}.choice{padding:14px;border:1px solid var(--line);border-radius:12px;background:#202631;color:#fff;font-weight:900;cursor:pointer}.choice.good{outline:2px solid var(--green)}.choice.bad{outline:2px solid #ff6969}.quiz-result{min-height:44px;margin-top:14px;font-weight:850}
.faq details{background:var(--panel);border:1px solid var(--line);border-radius:15px;padding:16px 18px;margin:9px 0}.faq summary{font-weight:900;cursor:pointer}.sources{color:var(--muted);border-top:1px solid var(--line);padding-top:20px}.sources a{color:#a9e8ff}
.next-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.next-card{background:var(--panel);border:1px solid var(--line);border-radius:18px;padding:19px;text-decoration:none}.next-card strong{display:block;margin:5px 0}.next-card small{color:var(--muted)}
@media(max-width:820px){.isdn-grid,.channel-grid,.compare{grid-template-columns:1fr}.ntba{justify-self:center;width:min(100%,420px)}.fact-strip{grid-template-columns:1fr 1fr}.isdn-hero h1{font-size:clamp(3rem,14vw,5rem)}.channels,.phone-sim,.quiz-options,.next-cards{grid-template-columns:1fr}}