:root{
  --bg:#060E1C; --bg2:#0A1628; --panel:#0E1D33; --panel2:#13243F;
  --ink:#E5EEF8; --muted:#8FA6C0; --line:#1E3354;
  --cyan:#22D3EE; --amber:#FCD34D; --red:#F87171; --green:#34D399; --violet:#A78BFA;
}
*{box-sizing:border-box}
body{margin:0; background:var(--bg); color:var(--ink);
  font-family:"Manrope","Inter",system-ui,Segoe UI,Roboto,sans-serif; line-height:1.55; padding:0 0 80px}
a{color:var(--cyan)}
img{max-width:100%}
header{padding:38px 20px 18px; text-align:center; background:linear-gradient(180deg,var(--bg2),transparent); border-bottom:1px solid var(--line)}
header .tag{color:var(--cyan); font-family:"JetBrains Mono",monospace; font-size:12px; letter-spacing:1px; text-transform:uppercase}
header h1{margin:6px 0 4px; font-size:28px; letter-spacing:-.5px}
header p{color:var(--muted); margin:6px auto 0; font-size:15px; max-width:720px}
.wrap{max-width:1160px; margin:0 auto; padding:0 20px}

/* ===== progress rail ===== */
.railwrap{max-width:1160px;margin:18px auto 0;padding:0 20px}
.rail{display:flex;gap:8px;flex-wrap:wrap;align-items:stretch}
.rail a{flex:1 1 120px;min-width:120px;text-decoration:none;display:block;border:1px solid var(--line);border-radius:10px;padding:9px 12px;background:var(--panel);transition:.14s}
.rail a:hover{border-color:var(--cyan);transform:translateY(-2px)}
.rail a .rn{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--muted)}
.rail a .rt{font-size:13px;color:var(--ink);font-weight:700;margin-top:2px;line-height:1.25}
.rail a.cur{border-color:var(--cyan);background:linear-gradient(180deg,rgba(34,211,238,.12),transparent)}
.rail a.cur .rn{color:var(--cyan)}
.rail a.done .rt::after{content:" ✓";color:var(--green)}
@media(max-width:760px){.rail a{flex:1 1 45%;min-width:0}}

/* ===== NAV ===== */
.topnav{max-width:1160px;margin:14px auto 0;padding:0 20px}
.nav-back{display:inline-flex;align-items:center;gap:7px;text-decoration:none;font-family:"JetBrains Mono",monospace;font-size:13px;padding:7px 14px;border-radius:9px;border:1px solid var(--line);background:var(--panel);color:var(--muted)}
.nav-back:hover{border-color:var(--cyan);color:var(--cyan);background:rgba(34,211,238,.06)}
.modnav{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:14px;max-width:1160px;margin:38px auto 0;padding:18px;border:1px solid var(--line);border-radius:14px;background:linear-gradient(180deg,var(--panel),var(--bg2))}
.modnav .mn-label{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.06em;margin-bottom:4px}
.modnav .mn-title{font-size:15px;color:var(--ink);font-weight:700}
.nav-next{display:inline-flex;align-items:center;gap:9px;text-decoration:none;padding:12px 20px;border-radius:11px;background:var(--cyan);color:#04222b;font-weight:700;font-size:14px}
.nav-next:hover{filter:brightness(1.08)}
.nav-prev{display:inline-flex;align-items:center;gap:7px;text-decoration:none;font-family:"JetBrains Mono",monospace;font-size:13px;padding:9px 16px;border-radius:9px;border:1px solid var(--line);background:var(--panel2);color:var(--muted)}
.nav-prev:hover{border-color:var(--cyan);color:var(--cyan)}
@media(max-width:620px){.modnav{flex-direction:column;align-items:stretch}}

/* ===== SECTION SHELL ===== */
.section{margin-top:46px}
.sec-head{display:flex; align-items:baseline; gap:14px; flex-wrap:wrap; margin-bottom:6px}
.sec-num{font-family:"JetBrains Mono",monospace; font-size:13px; color:var(--cyan); border:1px solid var(--line); border-radius:8px; padding:4px 10px; background:var(--bg2)}
.sec-head h2{font-size:23px; margin:0; letter-spacing:-.3px}
.sec-sub{color:var(--muted); font-size:14.5px; margin:4px 0 0; max-width:820px; line-height:1.6}
.badges{display:flex; gap:7px; flex-wrap:wrap; margin:12px 0 2px}
.b{font-family:"JetBrains Mono",monospace; font-size:11px; letter-spacing:.04em; text-transform:uppercase; padding:4px 10px; border-radius:999px; border:1px solid var(--line)}
.b.fgos{color:var(--green); background:rgba(52,211,153,.08); border-color:rgba(52,211,153,.35)}
.b.fop{color:var(--violet); background:rgba(167,139,250,.08); border-color:rgba(167,139,250,.35)}
.b.exam{color:var(--amber); background:rgba(252,211,77,.08); border-color:rgba(252,211,77,.35)}

/* intro card */
.intro{background:var(--panel); border:1px solid var(--line); border-left:4px solid var(--amber); border-radius:14px; padding:20px 22px; margin-top:26px}
.intro p{margin:8px 0; font-size:15px; color:#d7e3f2; line-height:1.7}
.intro p:first-child{margin-top:0}
.intro b{color:var(--ink)}
.intro .hook{font-size:16px;color:var(--ink)}

/* theory card */
.theory{background:var(--panel); border:1px solid var(--line); border-radius:14px; padding:20px 22px; margin-top:18px}
.theory h4{font-size:15px; color:var(--cyan); margin:18px 0 6px; border-left:3px solid var(--cyan); padding-left:10px}
.theory h4:first-child{margin-top:4px}
.theory p{font-size:14.5px; line-height:1.7; color:#d7e3f2; margin:8px 0}
.theory b{color:var(--ink)}
.theory i{color:#cfe0f1}
.theory code,.mono{font-family:"JetBrains Mono",monospace; font-size:.92em; background:var(--bg2); border:1px solid var(--line); border-radius:5px; padding:1px 6px; color:var(--amber)}
.theory ul,.theory ol{margin:8px 0; padding-left:20px}
.theory li{font-size:14.5px; line-height:1.7; color:#d7e3f2; margin:4px 0}
.callout{background:var(--bg2); border:1px solid var(--line); border-left:3px solid var(--violet); border-radius:10px; padding:12px 14px; margin:14px 0; font-size:13.5px; color:#cdddef}
.callout .ct{font-family:"JetBrains Mono",monospace; font-size:11px; text-transform:uppercase; letter-spacing:.06em; color:var(--violet); display:block; margin-bottom:4px}
.callout.amber{border-left-color:var(--amber)} .callout.amber .ct{color:var(--amber)}
.callout.cyan{border-left-color:var(--cyan)} .callout.cyan .ct{color:var(--cyan)}
.callout.green{border-left-color:var(--green)} .callout.green .ct{color:var(--green)}
.callout.red{border-left-color:var(--red)} .callout.red .ct{color:var(--red)}

/* figure */
.fig{margin:16px 0 6px;background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px;text-align:center}
.fig svg{width:100%;height:auto;max-width:760px;display:block;margin:0 auto}
.fig .cap{margin-top:10px;font-size:12.5px;color:var(--muted);font-family:"JetBrains Mono",monospace}
.fig .cap b{color:var(--amber)}

/* analogy grid */
.agrid{display:grid; grid-template-columns:repeat(auto-fill,minmax(240px,1fr)); gap:14px; margin-top:16px}
.acard{background:var(--panel); border:1px solid var(--line); border-radius:12px; padding:16px; border-top:3px solid var(--cyan); transition:.15s}
.acard:hover{border-color:var(--cyan); transform:translateY(-2px); box-shadow:0 8px 28px rgba(34,211,238,.16)}
.acard .ico{font-size:26px; line-height:1; margin-bottom:8px}
.acard h5{margin:0 0 4px; font-size:16px}
.acard .ana{font-family:"JetBrains Mono",monospace; font-size:12px; color:var(--amber); margin:0 0 8px}
.acard p{margin:0; font-size:13px; color:var(--muted); line-height:1.55}

/* tables */
.tblbox{margin:16px 0 6px; overflow:auto; border:1px solid var(--line); border-radius:12px}
table.dt{width:100%; border-collapse:collapse; font-size:13.5px; min-width:520px}
table.dt th{background:var(--panel2); color:var(--amber); text-align:left; padding:9px 12px; border-bottom:1px solid var(--line); font-weight:700; font-size:12.5px}
table.dt td{padding:9px 12px; border-bottom:1px solid var(--line); color:#d7e3f2; vertical-align:top}
table.dt tr:last-child td{border-bottom:none}
table.dt tr:nth-child(even) td{background:rgba(255,255,255,.02)}
table.dt td:first-child{color:var(--cyan); font-family:"JetBrains Mono",monospace; white-space:nowrap}
table.dt td.txt:first-child{color:#d7e3f2;font-family:inherit;white-space:normal}

/* ===== INTERACTIVE shell ===== */
.iv{background:var(--panel); border:1px solid var(--line); border-radius:16px; margin-top:18px; overflow:hidden}
.iv-head{display:flex; align-items:center; gap:12px; padding:14px 18px; background:linear-gradient(180deg,var(--panel2),transparent); border-bottom:1px solid var(--line)}
.iv-head .iv-ico{font-size:22px; line-height:1}
.iv-head .iv-t{flex:1}
.iv-head h3{margin:0; font-size:17px}
.iv-head .iv-s{font-size:12px; color:var(--muted); font-family:"JetBrains Mono",monospace; margin-top:2px}
.iv-head .iv-tag{font-family:"JetBrains Mono",monospace; font-size:11px; text-transform:uppercase; letter-spacing:.06em; color:var(--cyan); border:1px solid var(--line); border-radius:999px; padding:4px 10px;white-space:nowrap}
.iv-body{padding:18px}
.btn{cursor:pointer; font-family:inherit; font-size:13.5px; font-weight:600; border-radius:9px; padding:9px 16px; border:1px solid var(--line); background:var(--panel2); color:var(--ink); transition:.13s}
.btn:hover{border-color:var(--cyan); color:var(--cyan)}
.btn.primary{background:var(--cyan); color:#04222b; border-color:var(--cyan)}
.btn.primary:hover{filter:brightness(1.08); color:#04222b}
.btn:disabled{opacity:.45; cursor:not-allowed}
.btnrow{display:flex; gap:10px; flex-wrap:wrap; margin-top:14px}
.feed{margin-top:14px; font-size:13.5px; min-height:22px; font-family:"JetBrains Mono",monospace}
.feed.good{color:var(--green)} .feed.warn{color:var(--amber)} .feed.bad{color:var(--red)}

/* ===== Topology explorer ===== */
.topo-wrap{display:grid;grid-template-columns:1fr 320px;gap:18px}
@media(max-width:820px){.topo-wrap{grid-template-columns:1fr}}
.topo-svg{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:14px;cursor:pointer}
.topo-svg svg{width:100%;height:auto;display:block}
.topo-node{fill:var(--panel2);stroke:var(--line);stroke-width:2;transition:.2s;cursor:pointer}
.topo-node:hover,.topo-node.on{fill:rgba(34,211,238,.18);stroke:var(--cyan);stroke-width:2.5}
.topo-label{fill:var(--ink);font-size:12px;font-weight:700;text-anchor:middle;pointer-events:none;font-family:"Manrope",sans-serif}
.topo-line{stroke:var(--line);stroke-width:2;fill:none;transition:.2s}
.topo-line.on{stroke:var(--cyan);stroke-width:2.5}
.topo-info{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px}
.topo-info .ti-name{font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--cyan);text-transform:uppercase;letter-spacing:.06em}
.topo-info h4{margin:4px 0 8px;font-size:18px}
.topo-info p{margin:0 0 8px;font-size:13.5px;color:#cdddef;line-height:1.6}
.topo-info .pros{color:var(--green);font-size:13px}
.topo-info .cons{color:var(--red);font-size:13px}
.topo-info .use{margin-top:8px;font-size:12.5px;color:var(--muted);border-top:1px dashed var(--line);padding-top:8px}
@media(max-width:560px){
  .topo-svg{padding:8px}
  .topo-node{stroke-width:3}
  .topo-label{font-size:14px}
}

/* ===== Equipment matching ===== */
.eq-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
@media(max-width:760px){.eq-grid{grid-template-columns:1fr}}
.eq-pool,.eq-slots{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:14px;min-height:120px}
.eq-pool h4,.eq-slots h4{margin:0 0 10px;font-size:13px;text-transform:uppercase;letter-spacing:.05em;color:var(--amber);font-family:"JetBrains Mono",monospace}
.eq-chip{display:flex;align-items:center;gap:10px;background:var(--panel2);border:1px solid var(--line);border-radius:9px;padding:10px 14px;margin:8px 0;cursor:grab;font-size:13.5px;transition:.12s}
.eq-chip:hover{border-color:var(--cyan)}
.eq-chip.selected{border-color:var(--amber);background:rgba(252,211,77,.1);box-shadow:0 0 0 2px rgba(252,211,77,.3)}
.eq-chip.dragging{opacity:.4}
.eq-chip .eqi{font-size:20px}
.eq-slot{border:1.5px dashed var(--line);border-radius:9px;padding:12px 14px;margin:10px 0;min-height:50px;transition:.12s}
.eq-slot .eq-desc{font-size:12.5px;color:var(--muted);margin-bottom:6px}
.eq-slot.over{border-color:var(--cyan);background:rgba(34,211,238,.06)}
.eq-slot.ok{border-style:solid;border-color:var(--green);background:rgba(52,211,153,.07)}
.eq-slot.bad{border-style:solid;border-color:var(--red);background:rgba(248,113,113,.07)}
.eq-slot .placed{display:flex;align-items:center;gap:8px;font-size:13.5px;font-weight:600}

/* ===== Packet journey ===== */
.pj-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px}
.pj-svg{width:100%;height:auto;display:block;margin-bottom:14px}
.pj-node{fill:var(--panel2);stroke:var(--line);stroke-width:2;transition:.3s}
.pj-node.active{fill:rgba(34,211,238,.25);stroke:var(--cyan);stroke-width:3}
.pj-label{fill:var(--ink);font-size:11px;font-weight:700;text-anchor:middle;pointer-events:none;font-family:"JetBrains Mono",monospace}
.pj-line{stroke:var(--line);stroke-width:2;fill:none}
.pj-packet{fill:var(--amber);opacity:0;transition:.3s}
.pj-packet.moving{opacity:1}
.pj-info{background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:14px;margin-top:12px}
.pj-step{font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--cyan);text-transform:uppercase;letter-spacing:.06em}
.pj-info h4{margin:4px 0 8px;font-size:16px}
.pj-info p{margin:0;font-size:13.5px;color:#cdddef;line-height:1.6}

/* ===== DNS simulator ===== */
.dns-wrap{display:grid;grid-template-columns:1fr 1fr;gap:16px}
@media(max-width:760px){.dns-wrap{grid-template-columns:1fr}}
.dns-input{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:14px}
.dns-input label{font-size:12px;color:var(--muted);font-family:"JetBrains Mono",monospace;display:block;margin-bottom:6px}
.dns-input input{width:100%;background:#03101f;border:1px solid var(--line);border-radius:9px;padding:10px 13px;color:var(--cyan);font-family:"JetBrains Mono",monospace;font-size:14px;outline:none}
.dns-input input:focus{border-color:var(--cyan)}
.dns-result{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:14px;font-family:"JetBrains Mono",monospace;font-size:13px;min-height:120px}
.dns-result .dr-line{margin:4px 0;color:#cdddef}
.dns-result .dr-ok{color:var(--green)}
.dns-result .dr-err{color:var(--red)}
.dns-result .dr-ip{color:var(--amber);font-weight:600}

/* ===== Phishing email analyzer ===== */
.phish-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:12px;overflow:hidden}
.phish-email{background:#fff;color:#222;padding:0;font-family:Arial,Helvetica,sans-serif;font-size:14px}
.phish-header{background:#f5f5f5;border-bottom:1px solid #ddd;padding:12px 16px}
.phish-row{display:flex;gap:8px;margin:3px 0;font-size:13px;line-height:1.4}
.phish-row .ph-label{color:#666;min-width:60px;font-weight:700}
.phish-row .ph-val{color:#222;word-break:break-all}
.phish-body{padding:16px}
.phish-body .ph-greeting{font-size:15px;margin:0 0 12px}
.phish-body .ph-text{font-size:14px;line-height:1.6;margin:0 0 14px;color:#333}
.phish-body .ph-btn{display:inline-block;background:#1a73e8;color:#fff;padding:10px 24px;border-radius:4px;font-size:14px;font-weight:700;text-decoration:none;cursor:pointer;border:none}
.phish-body .ph-footer{margin-top:16px;font-size:11px;color:#999;border-top:1px solid #eee;padding-top:10px}
.phish-flag{cursor:pointer;position:relative;transition:.15s;border-radius:4px}
.phish-flag:hover{background:rgba(248,113,113,.15);outline:2px dashed var(--red)}
.phish-flag.found{background:rgba(248,113,113,.12);outline:2px solid var(--red)}
.phish-flag .ph-tooltip{display:none;position:relative;margin-top:8px;background:var(--panel);color:var(--ink);border:1px solid var(--red);border-radius:8px;padding:10px 12px;font-size:12px;font-family:"Manrope",sans-serif;line-height:1.5}
.phish-flag.found .ph-tooltip{display:block}
.phish-flag .ph-tooltip b{color:var(--red)}
.phish-counter{display:flex;align-items:center;gap:12px;padding:12px 16px;background:var(--panel);border-top:1px solid var(--line);font-size:13px}
.phish-counter .ph-found{font-family:"JetBrains Mono",monospace;color:var(--amber);font-weight:700}

/* ===== Packet structure explorer ===== */
.pkt-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px}
.pkt-stack{display:flex;flex-direction:column;gap:0;margin-bottom:14px}
.pkt-layer{border:2px solid var(--line);border-radius:10px;padding:12px 16px;cursor:pointer;transition:.18s;position:relative}
.pkt-layer:hover{border-color:var(--cyan)}
.pkt-layer.active{border-color:var(--cyan);background:rgba(34,211,238,.06)}
.pkt-layer .pl-head{display:flex;align-items:center;gap:10px}
.pkt-layer .pl-badge{font-family:"JetBrains Mono",monospace;font-size:11px;text-transform:uppercase;letter-spacing:.04em;padding:3px 8px;border-radius:6px;border:1px solid var(--line);white-space:nowrap}
.pkt-layer .pl-name{font-size:15px;font-weight:700;color:var(--ink)}
.pkt-layer .pl-size{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--muted);margin-left:auto}
.pkt-layer .pl-fields{display:none;margin-top:10px;padding-top:10px;border-top:1px dashed var(--line)}
.pkt-layer.active .pl-fields{display:block}
.pkt-layer .pl-fields table{width:100%;border-collapse:collapse;font-size:12.5px}
.pkt-layer .pl-fields th{text-align:left;color:var(--amber);font-family:"JetBrains Mono",monospace;font-size:11px;padding:4px 8px;border-bottom:1px solid var(--line)}
.pkt-layer .pl-fields td{padding:4px 8px;color:#cdddef;border-bottom:1px solid rgba(30,51,84,.5)}
.pkt-layer .pl-fields td:first-child{font-family:"JetBrains Mono",monospace;color:var(--cyan);white-space:nowrap;width:140px}
.pkt-layer.l0{margin:0;background:rgba(167,139,250,.04);border-color:rgba(167,139,250,.3)}
.pkt-layer.l0 .pl-badge{color:var(--violet);border-color:rgba(167,139,250,.4)}
.pkt-layer.l0.active{border-color:var(--violet);background:rgba(167,139,250,.08)}
.pkt-layer.l1{margin:0 16px;background:rgba(34,211,238,.04);border-color:rgba(34,211,238,.3)}
.pkt-layer.l1 .pl-badge{color:var(--cyan);border-color:rgba(34,211,238,.4)}
.pkt-layer.l1.active{border-color:var(--cyan);background:rgba(34,211,238,.08)}
.pkt-layer.l2{margin:0 32px;background:rgba(252,211,77,.04);border-color:rgba(252,211,77,.3)}
.pkt-layer.l2 .pl-badge{color:var(--amber);border-color:rgba(252,211,77,.4)}
.pkt-layer.l2.active{border-color:var(--amber);background:rgba(252,211,77,.08)}
.pkt-layer.l3{margin:0 48px;background:rgba(52,211,153,.04);border-color:rgba(52,211,153,.3)}
.pkt-layer.l3 .pl-badge{color:var(--green);border-color:rgba(52,211,153,.4)}
.pkt-layer.l3.active{border-color:var(--green);background:rgba(52,211,153,.08)}
.pkt-desc{background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:14px;margin-top:12px}
.pkt-desc h4{margin:0 0 6px;font-size:15px;color:var(--cyan)}
.pkt-desc p{margin:0;font-size:13.5px;color:#cdddef;line-height:1.6}

/* ===== Page load timeline ===== */
.pl-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px}
.pl-timeline{position:relative;padding-left:36px;margin-bottom:14px}
.pl-tl-step{position:relative;padding:10px 14px;margin-bottom:8px;border:1px solid var(--line);border-radius:10px;background:var(--panel);opacity:.35;transition:.3s}
.pl-tl-step.active{opacity:1;border-color:var(--cyan);background:rgba(34,211,238,.06)}
.pl-tl-step.done{opacity:.7;border-color:var(--green);background:rgba(52,211,153,.04)}
.pl-tl-step::before{content:"";position:absolute;left:-28px;top:50%;transform:translateY(-50%);width:16px;height:16px;border-radius:50%;border:2px solid var(--line);background:var(--bg2);transition:.3s}
.pl-tl-step.active::before{border-color:var(--cyan);background:var(--cyan);box-shadow:0 0 12px rgba(34,211,238,.5)}
.pl-tl-step.done::before{border-color:var(--green);background:var(--green)}
.pl-tl-step::after{content:"";position:absolute;left:-21px;top:0;bottom:-8px;width:2px;background:var(--line)}
.pl-tl-step:last-child::after{display:none}
.pl-tl-step .pls-num{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--cyan);text-transform:uppercase;letter-spacing:.04em}
.pl-tl-step .pls-title{font-size:14px;font-weight:700;color:var(--ink);margin:2px 0}
.pl-tl-step .pls-desc{font-size:12.5px;color:var(--muted);line-height:1.5;margin:0}
.pl-tl-step .pls-time{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--amber);float:right;margin-top:2px}
.pl-tl-step .pls-visual{margin-top:8px;padding:8px 10px;background:var(--bg2);border-radius:8px;font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--muted);display:none}
.pl-tl-step.active .pls-visual{display:block}
.pl-controls{display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.pl-speed{font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--muted)}
@media(max-width:560px){.pkt-layer.l1,.pkt-layer.l2,.pkt-layer.l3{margin-left:0;margin-right:0}}

/* ===== Search challenge ===== */
.sc-task{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px;margin-bottom:14px}
.sc-task .sc-num{font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--cyan);text-transform:uppercase;letter-spacing:.05em}
.sc-task .sc-desc{font-size:14.5px;color:var(--ink);margin:8px 0 12px;line-height:1.6}
.sc-opts{display:grid;gap:8px}
.sc-opt{cursor:pointer;background:var(--panel2);border:1px solid var(--line);border-radius:9px;padding:10px 13px;font-size:13.5px;font-family:"JetBrains Mono",monospace;color:var(--ink);transition:.12s;text-align:left}
.sc-opt:hover{border-color:var(--cyan)}
.sc-opt.correct{border-color:var(--green);background:rgba(52,211,153,.08)}
.sc-opt.wrong{border-color:var(--red);background:rgba(248,113,113,.08)}
.sc-opt .why{display:none;margin-top:8px;font-size:12px;color:var(--muted);font-family:inherit;border-top:1px dashed var(--line);padding-top:6px}
.sc-opt.reveal .why{display:block}
.sc-score{margin-top:16px;padding:14px;background:var(--panel);border:1px solid var(--line);border-radius:12px;text-align:center}
.sc-score .big{font-size:24px;font-weight:800;color:var(--amber);font-family:"JetBrains Mono",monospace}

/* ===== Fact-check lab ===== */
.fc-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:14px}
.fc-card{background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:16px;cursor:pointer;transition:.15s}
.fc-card:hover{border-color:var(--cyan);transform:translateY(-2px)}
.fc-card .fc-src{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.04em;margin-bottom:6px}
.fc-card h5{margin:0 0 8px;font-size:15px;color:var(--ink)}
.fc-card p{margin:0;font-size:13px;color:var(--muted);line-height:1.55}
.fc-card .fc-verdict{display:none;margin-top:10px;padding:10px;border-radius:8px;font-size:12.5px}
.fc-card .fc-verdict.show{display:block}
.fc-card .fc-verdict.ok{background:rgba(52,211,153,.08);border:1px solid rgba(52,211,153,.4);color:var(--green)}
.fc-card .fc-verdict.bad{background:rgba(248,113,113,.08);border:1px solid rgba(248,113,113,.4);color:var(--red)}

/* ===== Password strength ===== */
.pw-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px}
.pw-input{width:100%;background:#03101f;border:1px solid var(--line);border-radius:9px;padding:11px 14px;color:var(--ink);font-family:"JetBrains Mono",monospace;font-size:15px;outline:none;margin-bottom:12px}
.pw-input:focus{border-color:var(--cyan)}
.pw-meter{height:10px;background:var(--panel2);border-radius:999px;overflow:hidden;margin-bottom:8px}
.pw-meter-fill{height:100%;width:0;transition:.3s;border-radius:999px}
.pw-meter-fill.weak{background:var(--red)}
.pw-meter-fill.medium{background:var(--amber)}
.pw-meter-fill.strong{background:var(--green)}
.pw-label{font-family:"JetBrains Mono",monospace;font-size:13px;margin-bottom:10px}
.pw-label.weak{color:var(--red)}
.pw-label.medium{color:var(--amber)}
.pw-label.strong{color:var(--green)}
.pw-checks{display:grid;gap:6px}
.pw-check{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--muted)}
.pw-check.pass{color:var(--green)}
.pw-check .pw-ico{width:18px;text-align:center}

/* ===== Security scenario ===== */
.sec-scenario{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px;margin-bottom:14px}
.sec-scenario .ss-num{font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--cyan);text-transform:uppercase;letter-spacing:.05em}
.sec-scenario .ss-sit{font-size:14px;color:#d7e3f2;margin:8px 0 12px;line-height:1.7}
.sec-scenario .ss-sit code{font-family:"JetBrains Mono",monospace;background:var(--panel);border:1px solid var(--line);border-radius:5px;padding:1px 6px;color:var(--amber);font-size:.92em}
.sec-opts{display:grid;gap:8px}
.sec-opt{cursor:pointer;background:var(--panel2);border:1px solid var(--line);border-radius:9px;padding:10px 13px;font-size:13.5px;color:var(--ink);transition:.12s;text-align:left}
.sec-opt:hover{border-color:var(--cyan)}
.sec-opt.correct{border-color:var(--green);background:rgba(52,211,153,.08)}
.sec-opt.wrong{border-color:var(--red);background:rgba(248,113,113,.08)}
.sec-opt .why{display:none;margin-top:8px;font-size:12px;color:var(--muted);border-top:1px dashed var(--line);padding-top:6px}
.sec-opt.reveal .why{display:block}

/* ===== Quest (exam) ===== */
.quest{background:var(--panel);border:1px solid var(--line);border-radius:16px;margin-top:18px;overflow:hidden}
.quest-bar{display:flex;align-items:center;gap:14px;padding:14px 18px;background:linear-gradient(180deg,var(--panel2),transparent);border-bottom:1px solid var(--line);flex-wrap:wrap}
.quest-bar .xp{font-family:"JetBrains Mono",monospace;font-size:13px;color:var(--amber)}
.quest-bar .prog{flex:1;min-width:120px;height:8px;background:var(--bg2);border:1px solid var(--line);border-radius:999px;overflow:hidden}
.quest-bar .prog i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--cyan),var(--green));transition:.4s}
.quest-body{padding:18px}
.quest .qn{font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--cyan);text-transform:uppercase;letter-spacing:.05em}
.quest .qtext{font-size:15px;color:var(--ink);margin:8px 0 14px;line-height:1.6}
.quest .qtext code{font-family:"JetBrains Mono",monospace;background:var(--bg2);border:1px solid var(--line);border-radius:5px;padding:1px 6px;color:var(--amber)}
.quest-fb{margin-top:14px;padding:12px 14px;border-radius:10px;font-size:13.5px;display:none}
.quest-fb.show{display:block}
.quest-fb.ok{background:rgba(52,211,153,.08);border:1px solid rgba(52,211,153,.4);color:var(--green)}
.quest-fb.no{background:rgba(248,113,113,.08);border:1px solid rgba(248,113,113,.4);color:var(--red)}
.quest-done{text-align:center;padding:30px 18px}
.quest-done .big{font-size:34px;font-family:"JetBrains Mono",monospace;font-weight:800;color:var(--amber)}
.quest-done p{color:var(--muted);margin:8px 0 0}

/* ===== Final test ===== */
.q{background:var(--panel); border:1px solid var(--line); border-radius:12px; padding:16px 18px; margin-top:14px}
.q .qn{font-family:"JetBrains Mono",monospace; font-size:12px; color:var(--cyan); text-transform:uppercase; letter-spacing:.05em}
.q .qtype{font-family:"JetBrains Mono",monospace; font-size:11px; color:var(--muted); float:right}
.q .qtext{font-size:14.5px; color:var(--ink); margin:8px 0 12px; line-height:1.6}
.q .qtext code{font-family:"JetBrains Mono",monospace; background:var(--bg2); border:1px solid var(--line); border-radius:5px; padding:1px 6px; color:var(--amber); font-size:.92em}
.ans{display:grid; gap:8px}
.ans label{display:flex; align-items:center; gap:10px; background:var(--bg2); border:1px solid var(--line); border-radius:9px; padding:10px 13px; font-size:13.5px; cursor:pointer; transition:.1s}
.ans label:hover{border-color:var(--cyan)}
.ans input{accent-color:var(--cyan)}
.ans.match .mrow{display:flex; align-items:center; gap:10px; background:var(--bg2); border:1px solid var(--line); border-radius:9px; padding:8px 12px}
.ans.match .mrow .ml{flex:1; font-size:13.5px}
.ans.match select,.q input.txt{background:var(--panel2); color:var(--ink); border:1px solid var(--line); border-radius:8px; padding:7px 10px; font-family:inherit; font-size:13.5px}
.q input.txt{width:160px}
.seq{display:grid; gap:8px}
.seq .srow{display:flex; align-items:center; gap:10px; background:var(--bg2); border:1px solid var(--line); border-radius:9px; padding:8px 12px}
.seq .srow .sl{flex:1; font-size:13.5px}
.seq select{background:var(--panel2); color:var(--ink); border:1px solid var(--line); border-radius:8px; padding:6px 9px; font-family:"JetBrains Mono",monospace; font-size:13px; width:64px}
.q.correct{border-color:var(--green); box-shadow:0 0 0 1px rgba(52,211,153,.4)}
.q.wrong{border-color:var(--red); box-shadow:0 0 0 1px rgba(248,113,113,.4)}
.q .qfb{margin-top:10px; font-size:13px; display:none}
.q.correct .qfb,.q.wrong .qfb{display:block}
.q.correct .qfb{color:var(--green)} .q.wrong .qfb{color:var(--red)}
.q .qfb b{color:var(--ink)}
.testbar{display:flex; align-items:center; gap:16px; flex-wrap:wrap; margin-top:20px; padding:16px 18px; background:var(--panel); border:1px solid var(--line); border-radius:12px}
.score{font-size:20px; font-weight:800}
.score.big{font-family:"JetBrains Mono",monospace}
.scoremsg{font-size:13.5px; color:var(--muted)}

/* extended task */
.ext{background:var(--panel); border:1px solid var(--line); border-left:4px solid var(--violet); border-radius:14px; padding:20px 22px; margin-top:20px}
.ext h4{margin:0 0 6px; font-size:16px; color:var(--violet)}
.ext p{font-size:14px; color:#d7e3f2; line-height:1.7; margin:8px 0}
.ext textarea{width:100%; min-height:140px; background:var(--bg2); border:1px solid var(--line); border-radius:10px; padding:12px; color:var(--ink); font-family:inherit; font-size:14px; line-height:1.6; resize:vertical; margin-top:6px}
.ext .crit{margin-top:14px; background:var(--bg2); border:1px solid var(--line); border-radius:10px; padding:14px; display:none}
.ext .crit.show{display:block}
.ext .crit h5{margin:0 0 8px; font-size:13px; color:var(--amber); font-family:"JetBrains Mono",monospace; text-transform:uppercase}
.ext .crit ul{margin:0; padding-left:18px} .ext .crit li{font-size:13.5px; margin:5px 0; color:#cdddef}

/* ===== Logo carousel ===== */
.logo-carousel{position:relative;overflow:hidden;margin-top:16px;padding:6px 0;
  border:1px solid var(--line);border-radius:14px;background:linear-gradient(180deg,var(--panel),var(--bg2))}
.logo-carousel::before,.logo-carousel::after{content:"";position:absolute;top:0;bottom:0;width:60px;z-index:2;pointer-events:none}
.logo-carousel::before{left:0;background:linear-gradient(90deg,var(--bg2),transparent)}
.logo-carousel::after{right:0;background:linear-gradient(270deg,var(--bg2),transparent)}
.logo-track{display:flex;gap:14px;width:max-content;will-change:transform;
  animation:logoScroll 80s linear infinite}
.logo-carousel:hover .logo-track{animation-play-state:paused}
@keyframes logoScroll{from{transform:translateX(0)}to{transform:translateX(-50%)}}
.logo-item{flex:0 0 auto;width:118px;height:104px;display:flex;flex-direction:column;
  align-items:center;justify-content:center;gap:8px;padding:10px 8px;
  border:1px solid var(--line);border-radius:12px;background:var(--panel);
  text-decoration:none;transition:border-color .15s,transform .15s,box-shadow .15s}
.logo-item:hover{border-color:var(--cyan);transform:translateY(-3px);
  box-shadow:0 8px 26px rgba(34,211,238,.18)}
.logo-item.ru{border-color:rgba(52,211,153,.4)}
.logo-item.ru:hover{border-color:var(--green);box-shadow:0 8px 26px rgba(52,211,153,.18)}
.logo-item img{width:54px;height:54px;object-fit:contain;display:block}
.logo-fallback{display:flex;align-items:center;justify-content:center;width:54px;height:54px;
  border-radius:10px;background:var(--bg2);color:var(--muted);font-size:11px;text-align:center;
  font-family:"JetBrains Mono",monospace;padding:2px;line-height:1.1}
.logo-cap{font-size:11.5px;color:#cdddef;text-align:center;line-height:1.2;
  max-width:104px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.logo-item.ru .logo-cap{color:var(--green)}

/* ===== Page load timeline ===== */
.pkt-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px}
.pkt-stack{display:flex;flex-direction:column;gap:0;margin-bottom:14px}
.pkt-layer{border:2px solid var(--line);border-radius:10px;padding:12px 16px;cursor:pointer;transition:.18s;position:relative}
.pkt-layer:hover{border-color:var(--cyan)}
.pkt-layer.active{border-color:var(--cyan);background:rgba(34,211,238,.06)}
.pkt-layer .pl-head{display:flex;align-items:center;gap:10px}
.pkt-layer .pl-badge{font-family:"JetBrains Mono",monospace;font-size:11px;text-transform:uppercase;letter-spacing:.04em;padding:3px 8px;border-radius:6px;border:1px solid var(--line);white-space:nowrap}
.pkt-layer .pl-name{font-size:15px;font-weight:700;color:var(--ink)}
.pkt-layer .pl-size{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--muted);margin-left:auto}
.pkt-layer .pl-fields{display:none;margin-top:10px;padding-top:10px;border-top:1px dashed var(--line)}
.pkt-layer.active .pl-fields{display:block}
.pkt-layer .pl-fields table{width:100%;border-collapse:collapse;font-size:12.5px}
.pkt-layer .pl-fields th{text-align:left;color:var(--amber);font-family:"JetBrains Mono",monospace;font-size:11px;padding:4px 8px;border-bottom:1px solid var(--line)}
.pkt-layer .pl-fields td{padding:4px 8px;color:#cdddef;border-bottom:1px solid rgba(30,51,84,.5)}
.pkt-layer .pl-fields td:first-child{font-family:"JetBrains Mono",monospace;color:var(--cyan);white-space:nowrap;width:140px}
.pkt-layer.l0{margin:0;background:rgba(167,139,250,.04);border-color:rgba(167,139,250,.3)}
.pkt-layer.l0 .pl-badge{color:var(--violet);border-color:rgba(167,139,250,.4)}
.pkt-layer.l0.active{border-color:var(--violet);background:rgba(167,139,250,.08)}
.pkt-layer.l1{margin:0 16px;background:rgba(34,211,238,.04);border-color:rgba(34,211,238,.3)}
.pkt-layer.l1 .pl-badge{color:var(--cyan);border-color:rgba(34,211,238,.4)}
.pkt-layer.l1.active{border-color:var(--cyan);background:rgba(34,211,238,.08)}
.pkt-layer.l2{margin:0 32px;background:rgba(252,211,77,.04);border-color:rgba(252,211,77,.3)}
.pkt-layer.l2 .pl-badge{color:var(--amber);border-color:rgba(252,211,77,.4)}
.pkt-layer.l2.active{border-color:var(--amber);background:rgba(252,211,77,.08)}
.pkt-layer.l3{margin:0 48px;background:rgba(52,211,153,.04);border-color:rgba(52,211,153,.3)}
.pkt-layer.l3 .pl-badge{color:var(--green);border-color:rgba(52,211,153,.4)}
.pkt-layer.l3.active{border-color:var(--green);background:rgba(52,211,153,.08)}
.pkt-desc{background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:14px;margin-top:12px}
.pkt-desc h4{margin:0 0 6px;font-size:15px;color:var(--cyan)}
.pkt-desc p{margin:0;font-size:13.5px;color:#cdddef;line-height:1.6}

/* ===== Page load timeline ===== */
.pl-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:16px}
.pl-timeline{position:relative;padding-left:36px;margin-bottom:14px}
.pl-tl-step{position:relative;padding:10px 14px;margin-bottom:8px;border:1px solid var(--line);border-radius:10px;background:var(--panel);opacity:.35;transition:.3s}
.pl-tl-step.active{opacity:1;border-color:var(--cyan);background:rgba(34,211,238,.06)}
.pl-tl-step.done{opacity:.7;border-color:var(--green);background:rgba(52,211,153,.04)}
.pl-tl-step::before{content:"";position:absolute;left:-28px;top:50%;transform:translateY(-50%);width:16px;height:16px;border-radius:50%;border:2px solid var(--line);background:var(--bg2);transition:.3s}
.pl-tl-step.active::before{border-color:var(--cyan);background:var(--cyan);box-shadow:0 0 12px rgba(34,211,238,.5)}
.pl-tl-step.done::before{border-color:var(--green);background:var(--green)}
.pl-tl-step::after{content:"";position:absolute;left:-21px;top:0;bottom:-8px;width:2px;background:var(--line)}
.pl-tl-step:last-child::after{display:none}
.pl-tl-step .pls-num{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--cyan);text-transform:uppercase;letter-spacing:.04em}
.pl-tl-step .pls-title{font-size:14px;font-weight:700;color:var(--ink);margin:2px 0}
.pl-tl-step .pls-desc{font-size:12.5px;color:var(--muted);line-height:1.5;margin:0}
.pl-tl-step .pls-time{font-family:"JetBrains Mono",monospace;font-size:11px;color:var(--amber);float:right;margin-top:2px}
.pl-tl-step .pls-visual{margin-top:8px;padding:8px 10px;background:var(--bg2);border-radius:8px;font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--muted);display:none}
.pl-tl-step.active .pls-visual{display:block}
.pl-controls{display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.pl-speed{font-family:"JetBrains Mono",monospace;font-size:12px;color:var(--muted)}
@media(max-width:560px){.pkt-layer.l1,.pkt-layer.l2,.pkt-layer.l3{margin-left:0;margin-right:0}}

/* ===== loading / error ===== */
.loadbox{margin-top:26px;padding:16px 18px;border:1px solid var(--line);border-radius:12px;background:var(--panel);color:var(--muted);font-family:"JetBrains Mono",monospace;font-size:13px}
.errbox{margin-top:26px;padding:16px 18px;border:1px solid rgba(248,113,113,.4);border-radius:12px;background:rgba(248,113,113,.07);color:var(--red);font-size:13.5px;display:none}
.errbox.show{display:block}

/* ── Network Type Quiz ── */
.ntq-wrap{display:flex;flex-direction:column;gap:12px}
.ntq-q{padding:14px;background:var(--panel);border:1px solid var(--line);border-radius:10px}
.ntq-desc{font-size:14px;color:var(--ink);margin-bottom:10px;line-height:1.5}
.ntq-opts{display:flex;flex-wrap:wrap;gap:8px}
.ntq-opt{padding:8px 16px;background:var(--bg2);border:1px solid var(--line);border-radius:8px;font-family:"JetBrains Mono",monospace;font-size:13px;color:var(--ink);cursor:pointer;transition:all .15s}
.ntq-opt:hover:not(.disabled){border-color:var(--cyan);background:var(--panel2)}
.ntq-opt.correct{border-color:var(--green);background:rgba(52,211,153,.15);color:var(--green)}
.ntq-opt.wrong{border-color:var(--red);background:rgba(248,113,113,.1);color:var(--red)}
.ntq-opt.disabled{opacity:.6;cursor:default;pointer-events:none}
.ntq-feed{margin-top:10px;font-size:13px;color:var(--muted);display:none}
.ntq-feed.show{display:block}

@media(max-width:560px){
  header h1{font-size:22px}
  .wrap{padding:0 13px}
  .sec-head h2{font-size:20px}
  .topo-wrap,.dns-wrap,.eq-grid{grid-template-columns:1fr}
  .logo-item{width:96px;height:92px}
  .logo-item img,.logo-fallback{width:44px;height:44px}
  .btn{padding:12px 18px;font-size:14px;min-height:44px}
  .btnrow{flex-direction:column}
  .btnrow .btn{width:100%}
  .ans label{padding:12px 14px;min-height:44px}
  .sc-opt,.sec-opt{padding:12px 14px;min-height:44px}
  .eq-chip{padding:12px 14px;min-height:48px}
  .eq-slot{min-height:56px}
  .dns-input input,.pw-input,.q input.txt{font-size:16px;padding:12px 14px}
  .pl-timeline{padding-left:32px}
  .pl-tl-step::before{left:-26px;width:14px;height:14px}
  .pl-tl-step::after{left:-20px}
  .pkt-layer .pl-fields td:first-child{width:auto;white-space:normal}
  .testbar{flex-direction:column;align-items:stretch;text-align:center}
  .testbar > div:last-child{margin-top:8px}
  .quest-bar{flex-direction:column;align-items:stretch}
  .phish-row{flex-direction:column;gap:2px}
  .phish-row .ph-label{min-width:auto}
  .fc-grid{grid-template-columns:1fr}
  .sc-opts,.sec-opts{gap:10px}
  .tblbox{margin-left:-13px;margin-right:-13px;border-radius:0;border-left:none;border-right:none}
}
@media(prefers-reduced-motion:reduce){
  *{animation:none !important; transition:none !important}
}