/* Study library and guide articles */
.lib3{display:flex;gap:10px;align-items:flex-end;justify-content:center;height:260px;perspective:700px}
.lib3 .bk{width:54px;border-radius:8px 8px 3px 3px;background:linear-gradient(90deg,rgba(0,0,0,.25),transparent 22%),var(--c);box-shadow:0 18px 30px rgba(0,0,0,.35);animation:bkf 6s ease-in-out infinite;position:relative}
.lib3 .bk:after{content:"";position:absolute;left:10px;right:10px;top:18px;height:3px;background:rgba(255,255,255,.55);box-shadow:0 8px 0 rgba(255,255,255,.35)}
.lib3 .b1{height:170px;--c:#12907f}.lib3 .b2{height:220px;--c:#ffb84d;animation-delay:-1s}.lib3 .b3{height:190px;--c:#2a6f9a;animation-delay:-2s}.lib3 .b4{height:240px;--c:#e8eef3;animation-delay:-3s}.lib3 .b5{height:160px;--c:#d96a4e;animation-delay:-4s}
@keyframes bkf{50%{transform:translateY(-12px) rotateY(10deg)}}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin:6px 0 4px}.chips a{padding:8px 16px;border-radius:99px;border:1.5px solid var(--line);background:#fff;color:var(--ink);font-weight:700;font-size:.9rem;min-height:40px;display:inline-flex;align-items:center}.chips a:hover{background:var(--navy);color:#fff;text-decoration:none;border-color:var(--navy)}
.gg{display:grid;grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:16px;margin-top:14px}
.gcard{display:flex;flex-direction:column;gap:8px;background:#fff;border:1px solid var(--line);border-radius:22px;padding:24px;color:var(--text);transition:transform .3s,box-shadow .3s,border-color .3s;position:relative;overflow:hidden}
.gcard:before{content:"";position:absolute;left:0;top:0;width:100%;height:4px;background:linear-gradient(90deg,var(--teal),var(--gold));transform:scaleX(0);transform-origin:0 50%;transition:transform .4s}
.gcard:hover{transform:translateY(-5px);box-shadow:var(--sh);text-decoration:none;border-color:var(--teal)}.gcard:hover:before{transform:none}
.gc-cat{font:700 .7rem var(--mono);letter-spacing:.14em;text-transform:uppercase;color:var(--teal)}
.gcard h3{font-size:1.2rem;margin:0}.gcard p{margin:0;font-size:.94rem;color:#2c3d4f;flex:1}
.gc-foot{display:flex;justify-content:space-between;align-items:center;margin-top:6px;font-size:.86rem}.gc-foot i{color:var(--mut);font-style:normal}.gc-foot b{color:var(--teal)}
/* guide article */
.ph5{padding-bottom:48px}.gd-hero{max-width:860px;margin:0 auto}.ph5 h1{font-size:clamp(1.9rem,4.2vw,3rem)}
.crumb-l{color:#8fb0c4;font-size:.86rem;margin-bottom:16px}.crumb-l a{color:#cfe0ea}
.gd-meta{color:#8fb0c4;font-size:.9rem;margin:10px 0 0}
.gd-wrap{display:grid;grid-template-columns:230px minmax(0,1fr);gap:48px;max-width:1040px;padding-top:26px;padding-bottom:30px}
.gd-toc{position:sticky;top:96px;align-self:start;font-size:.9rem;display:flex;flex-direction:column;gap:2px;border-left:2px solid var(--line)}
.gd-toc p{font:700 .7rem var(--mono);letter-spacing:.14em;text-transform:uppercase;color:var(--mut);margin:0 0 8px 14px}
.gd-toc a{padding:6px 14px;color:#33465a;border-left:2px solid transparent;margin-left:-2px;line-height:1.35}.gd-toc a:hover{color:var(--teal);text-decoration:none}.gd-toc a.on{border-color:var(--gold);color:var(--ink);font-weight:700}
.gd-art{font-size:1.06rem;line-height:1.75;color:#1f3042;max-width:none}
.gd-art h2{font-size:1.65rem;margin:2em 0 .5em;scroll-margin-top:96px}.gd-art h2:first-child{margin-top:0}
.gd-art h3{font-size:1.15rem}
.gd-steps{list-style:none;counter-reset:g;padding:0;margin:1em 0}.gd-steps li{counter-increment:g;position:relative;padding:4px 0 14px 54px}
.gd-steps li:before{content:counter(g);position:absolute;left:0;top:2px;width:36px;height:36px;border-radius:50%;background:var(--navy);color:var(--gold);display:grid;place-items:center;font:800 .95rem var(--disp)}
.gd-list{padding-left:1.2em}.gd-list li{margin:.35em 0}.gd-list li::marker{color:var(--teal)}
.gd-note,.gd-tip{margin:1.4em 0;padding:16px 18px;border-radius:16px;font-size:.97rem;line-height:1.6}
.gd-note{background:#fff7e6;border:1px solid #f1d18f;color:#5a4210}.gd-tip{background:var(--rose);border:1px solid #b9e0d8;color:#0b4a41}
.gd-tbl{overflow-x:auto;margin:1.2em 0;border:1px solid var(--line);border-radius:16px;background:#fff}.gd-tbl table{border-collapse:collapse;width:100%;min-width:420px}
.gd-tbl th{background:var(--navy);color:#fff;text-align:left;padding:10px 14px;font-size:.84rem;letter-spacing:.04em;white-space:normal}.gd-tbl td{padding:10px 14px;border-top:1px solid var(--line);vertical-align:top;white-space:normal;font-size:.96rem}.gd-tbl td:first-child{font:700 .95rem var(--mono);color:var(--teal);white-space:nowrap}
.gd-code{font:600 1rem var(--mono);padding:16px;border-radius:14px;background:#02090f;color:#6ff0cf;overflow-x:auto;white-space:nowrap}
.gd-cmp{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:1.2em 0}.gd-cmp>div{background:#fff;border:1px solid var(--line);border-radius:18px;padding:18px}.gd-cmp h3{margin-top:0}.gd-cmp ul{margin:0;padding-left:1.1em}
.gd-faq details{background:#fff;border:1px solid var(--line);border-radius:14px;margin-bottom:8px}.gd-faq summary{cursor:pointer;padding:14px 18px;font-weight:700;color:var(--ink);min-height:48px}.gd-faq p{padding:0 18px 14px;margin:0}
.gd-cta{display:flex;justify-content:space-between;align-items:center;gap:18px;flex-wrap:wrap;margin:2.2em 0 1em;padding:24px;border-radius:22px;background:linear-gradient(120deg,#0a1b2e,#12507a);color:#cfe0ea}.gd-cta b{color:#fff;font:800 1.2rem var(--disp)}.gd-cta p{margin:4px 0 0}.gd-ctab{display:flex;gap:10px;flex-wrap:wrap}
.gd-disc{font-size:.84rem;color:var(--mut)}
/* alphabet trainer */
.nato{margin:1.4em 0;padding:18px;border-radius:22px;background:linear-gradient(160deg,#0a1b2e,#10304a);color:#cfe0ea}
.nato-h{margin:0 0 12px;font-size:.92rem}
.nato-g{display:grid;grid-template-columns:repeat(auto-fill,minmax(92px,1fr));gap:8px}
.nt{position:relative;height:84px;border-radius:14px;border:1px solid #1d4262;background:#0c2236;color:#fff;cursor:pointer;perspective:600px;padding:0;font:inherit;transition:border-color .2s}
.nt:hover{border-color:var(--gold)}
.nt span{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;backface-visibility:hidden;transition:transform .45s}
.nt-f{font:800 2.2rem var(--disp);color:var(--gold)}.nt-b{transform:rotateY(180deg);line-height:1.2}.nt-b b{font-size:.98rem}.nt-b small{font:600 .62rem var(--mono);color:#7fe3cb;letter-spacing:.04em}
.nt[aria-pressed=true] .nt-f{transform:rotateY(180deg)}.nt[aria-pressed=true] .nt-b{transform:none}
@media(max-width:900px){.gd-wrap{grid-template-columns:1fr;gap:10px}.gd-toc{position:static;flex-direction:row;overflow-x:auto;border:0;gap:6px;padding-bottom:8px;scrollbar-width:none}.gd-toc p{display:none}.gd-toc a{flex:none;border:1.5px solid var(--line);border-radius:99px;margin:0;background:#fff;padding:8px 14px}.gd-toc a.on{background:var(--navy);color:#fff;border-color:var(--navy)}.gd-cmp{grid-template-columns:1fr}.lib3{height:190px}.lib3 .bk{width:40px}}
@media(prefers-reduced-motion:reduce){.lib3 .bk{animation:none}.nt span{transition:none}}
.gd-art .nato-h,.gd-art .gd-cta p{color:#cfe0ea}
.gd-art .gd-list li{background:none;border:0;padding:0;box-shadow:none}
.gd-wrap>*,.gd-art{min-width:0}.gd-code{max-width:100%}
@media(max-width:900px){.gd-wrap{grid-template-columns:minmax(0,1fr)}}