/* Dùng chung cho trang Hướng dẫn tập và các bài hướng dẫn */
:root{
  --canvas:#0F2427;
  --panel:#16343A;
  --panel-2:#1B3E45;
  --accent:#FF6A3D;
  --accent-hover:#FF8559;
  --mint:#9FD8CB;
  --text-secondary:#A9C6C0;
  --text-primary:#F4F1EA;
  --line:rgba(159,216,203,.16);
  --line-strong:rgba(159,216,203,.42);
  --ease-out:cubic-bezier(.22,1,.36,1);
  --ease-io:cubic-bezier(.65,0,.35,1);
  --tshadow:0 1px 2px rgba(5,14,16,.95),0 3px 12px rgba(5,14,16,.78),0 10px 44px rgba(5,14,16,.8);
  --f-display:"Big Shoulders Display","Arial Narrow",Impact,sans-serif;
  --f-body:"Be Vietnam Pro",system-ui,"Segoe UI",sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,Consolas,monospace;
}
*,*::before,*::after{box-sizing:border-box}
html{overflow-x:hidden;overflow-x:clip;-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:120px}
body{margin:0;overflow-x:hidden;overflow-x:clip;background:var(--canvas);color:var(--text-primary);font:400 17px/1.7 var(--f-body);-webkit-font-smoothing:antialiased;animation:pagein .9s var(--ease-out) both}
@keyframes pagein{from{opacity:0}to{opacity:1}}
img{max-width:100%;display:block}
a{color:inherit}
h1,h2,h3{font-family:var(--f-display);font-weight:900;line-height:1.24;letter-spacing:.01em;margin:0;text-transform:uppercase;text-wrap:balance}
p{margin:0}
.mono{font-family:var(--f-mono);font-weight:500;font-size:.78rem;letter-spacing:.14em;text-transform:uppercase}
.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}
.skip{position:fixed;left:16px;top:-60px;z-index:100;background:var(--accent);color:var(--canvas);padding:10px 16px;border-radius:10px;font-weight:700;text-decoration:none;transition:top .3s var(--ease-out)}
.skip:focus{top:16px}
:focus-visible{outline:3px solid var(--accent);outline-offset:3px;border-radius:6px}

.env{position:fixed;inset:0;z-index:-1;pointer-events:none;overflow:hidden}
.env::before{content:"";position:absolute;inset:-30%;background:radial-gradient(40% 35% at 70% 30%,rgba(255,106,61,.10),transparent 70%),radial-gradient(35% 30% at 25% 75%,rgba(159,216,203,.07),transparent 70%);animation:drift 72s var(--ease-io) -18s infinite alternate}
@keyframes drift{from{transform:translate3d(-4%,-3%,0) rotate(0deg)}to{transform:translate3d(5%,4%,0) rotate(8deg)}}

.nav{position:fixed;top:0;left:0;right:0;z-index:50;display:flex;align-items:center;justify-content:space-between;gap:24px;padding:14px clamp(16px,4vw,48px);background:rgba(15,36,39,.82);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px)}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;font-family:var(--f-display);font-weight:900;font-size:1.35rem;letter-spacing:.03em;text-transform:uppercase}
.brand svg{width:68px;height:68px;flex:none}
.nav ul{display:flex;gap:clamp(12px,2.2vw,30px);list-style:none;margin:0;padding:0}
.nav ul a{text-decoration:none;font-size:.92rem;font-weight:500;position:relative;padding:6px 0}
.nav ul a::after{content:"";position:absolute;left:0;right:0;bottom:0;height:2px;background:var(--accent);transform:scaleX(0);transform-origin:left;transition:transform .4s var(--ease-out)}
.nav ul a:hover::after,.nav ul a[aria-current="page"]::after{transform:scaleX(1)}
@media (max-width:900px){.nav ul{display:none}}

.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;padding:14px 26px;border-radius:999px;background:var(--accent);color:var(--canvas);font-weight:700;font-size:1rem;text-decoration:none;border:0;cursor:pointer;font-family:var(--f-body);transition:background .3s var(--ease-out),transform .3s var(--ease-out)}
.btn:hover{background:var(--accent-hover);transform:translateY(-2px)}
.link{font-weight:500;text-underline-offset:5px;text-decoration-color:var(--line-strong)}
.link:hover{text-decoration-color:var(--accent)}
@media (pointer:coarse){.btn{min-height:44px}}

.wrap{max-width:1180px;margin:0 auto}
.kicker{display:block;color:var(--mint);margin-bottom:18px}

.page-head{position:relative;padding:clamp(130px,16vw,190px) clamp(20px,6vw,96px) clamp(48px,6vw,80px);overflow:hidden}
.page-head > img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:.4}
.page-head::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(15,36,39,.9) 0%,rgba(15,36,39,.55) 45%,rgba(15,36,39,1) 100%)}
.page-head .wrap{position:relative;z-index:1}
.page-head h1{font-size:clamp(2.8rem,6.6vw,6rem);text-shadow:var(--tshadow);max-width:18ch}
.page-head .lede{margin-top:20px;max-width:56ch;font-size:clamp(1.05rem,1.4vw,1.25rem);font-weight:500;text-wrap:pretty;text-shadow:var(--tshadow)}

.pulse{display:block;width:100%;max-width:1180px;height:60px;margin:0 auto;padding:0 clamp(20px,6vw,96px);overflow:visible}
.pulse path{fill:none;stroke:var(--mint);stroke-width:2.5;stroke-linecap:round;stroke-linejoin:round;stroke-dasharray:1;stroke-dashoffset:1;animation:draw 1.8s var(--ease-out) .3s forwards}
@keyframes draw{to{stroke-dashoffset:0}}

main{padding:0 clamp(20px,6vw,96px) clamp(88px,10vw,140px)}

/* guide list */
.guides{margin-top:32px;display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:20px}
.guide{position:relative;display:flex;flex-direction:column;border-radius:22px;background:var(--panel);border:1px solid var(--line);overflow:hidden;text-decoration:none;transition:transform .45s var(--ease-out),border-color .45s var(--ease-out)}
a.guide:hover{transform:translateY(-4px);border-color:var(--line-strong)}
.guide .cover{aspect-ratio:16/10;display:grid;place-items:center;background:radial-gradient(80% 90% at 70% 20%,rgba(255,106,61,.18),transparent 70%),var(--panel-2)}
.guide .cover{overflow:hidden}
.guide .cover img{width:100%;height:100%;object-fit:cover}
.guide .cover svg{width:64px;height:64px;color:var(--mint)}
.guide .body{display:flex;flex-direction:column;gap:10px;padding:20px 22px 24px;flex:1}
.guide h2{font-family:var(--f-body);text-transform:none;letter-spacing:0;font-weight:700;font-size:1.15rem;line-height:1.4}
.guide p{color:var(--text-secondary);font-size:.95rem}
.guide .meta{color:var(--mint)}
.guide .go{margin-top:auto;font-weight:700;color:var(--accent)}
.guide.soon{opacity:.72}
.badge{position:absolute;top:14px;right:14px;padding:4px 10px;border-radius:999px;background:rgba(8,20,22,.8);border:1px solid var(--line-strong);color:var(--mint)}

/* article */
.crumbs{display:flex;flex-wrap:wrap;gap:8px;color:var(--mint);margin-bottom:18px}
.crumbs a{text-decoration:none}
.crumbs a:hover{text-decoration:underline}
.article-meta{margin-top:18px;display:flex;flex-wrap:wrap;gap:8px 18px;color:var(--text-secondary)}
.layout{max-width:1180px;margin:0 auto;display:grid;grid-template-columns:240px minmax(0,1fr);gap:clamp(24px,5vw,72px);align-items:start}
.toc{position:sticky;top:124px;padding:18px 0}
.toc ol{list-style:none;margin:12px 0 0;padding:0;display:grid;gap:8px;counter-reset:t}
.toc a{display:block;text-decoration:none;color:var(--text-secondary);font-size:.92rem;line-height:1.45;padding:4px 0;border-left:2px solid var(--line);padding-left:12px;transition:color .3s,border-color .3s}
.toc a:hover{color:var(--text-primary);border-color:var(--accent)}
@media (max-width:900px){.layout{grid-template-columns:minmax(0,1fr)}.toc{position:static;border:1px solid var(--line);border-radius:18px;padding:18px 20px}}

.prose{max-width:70ch}
.prose section{padding-top:28px;margin-top:28px;border-top:1px solid var(--line)}
.prose section:first-child{border-top:0;margin-top:0;padding-top:0}
.prose h2{font-size:clamp(1.9rem,3.4vw,2.6rem);margin-bottom:16px}
.prose h3{font-size:1.5rem;margin:26px 0 10px}
.faq-list h3{font-size:1.2rem;line-height:1.4;margin:22px 0 6px}
.faq-list h3:first-child{margin-top:4px}
.prose p{margin:0 0 14px;color:var(--text-primary)}
.prose ul,.prose ol{margin:0 0 16px;padding-left:1.3em}
.prose li{margin:6px 0}
.prose li::marker{color:var(--mint)}
.prose strong{color:var(--text-primary)}

.prose .steps{list-style:none;padding:0;margin:20px 0 0;display:grid;gap:18px;counter-reset:s}
.step{counter-increment:s;padding:22px 24px;border-radius:20px;background:var(--panel);border:1px solid var(--line)}
.step-head{display:flex;flex-wrap:wrap;align-items:baseline;gap:8px 14px;margin-bottom:12px}
.step-head::before{content:counter(s,decimal-leading-zero);font-family:var(--f-mono);color:var(--accent);font-size:.9rem}
.step h3{margin:0;font-size:1.55rem}
.chip{display:inline-block;padding:3px 10px;border-radius:999px;border:1px solid var(--line-strong);color:var(--mint);font-family:var(--f-mono);font-size:.74rem}
.step ol{margin:0 0 12px}
.tip,.avoid{margin:8px 0 0!important;padding-left:14px;border-left:3px solid var(--mint);color:var(--text-secondary)!important;font-size:.96rem}
.avoid{border-left-color:var(--accent)}
.tip b,.avoid b{color:var(--text-primary)}

.media{margin:6px 0 22px;border-radius:22px;overflow:hidden;background:var(--panel);border:1px solid var(--line)}
.media img,.media video{display:block;width:100%;height:auto;background:#081517}
.media video{aspect-ratio:1/1;max-height:560px;object-fit:contain}
.media figcaption{padding:12px 16px;color:var(--text-secondary);font-size:.9rem}
.media figcaption a{color:var(--text-primary)}
.callout{margin:20px 0;padding:22px 24px;border-radius:20px;background:linear-gradient(120deg,rgba(255,106,61,.12),rgba(22,52,58,.6));border:1px solid rgba(255,106,61,.4)}
.callout h3{margin-top:0}

.table-wrap{overflow-x:auto;margin:10px 0 18px}
table{border-collapse:collapse;width:100%;min-width:420px;font-size:.95rem}
th,td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--line)}
th{font-family:var(--f-mono);font-weight:500;font-size:.75rem;letter-spacing:.12em;text-transform:uppercase;color:var(--mint)}

.gear{margin-top:18px;display:grid;grid-template-columns:repeat(auto-fill,minmax(170px,1fr));gap:14px}
.gear-card{display:flex;flex-direction:column;border-radius:18px;background:var(--panel);border:1px solid var(--line);overflow:hidden}
.gear-card img{width:100%;height:auto;aspect-ratio:1/1;object-fit:cover;background:#fff}
.gear-card .in{display:flex;flex-direction:column;gap:8px;padding:14px 16px 18px;flex:1}
.gear-card h4{margin:0;font-size:1rem;line-height:1.4}
.gear-card .role{color:var(--mint);font-size:.88rem}
.gear-card .btn{margin-top:auto;align-self:flex-start;padding:10px 18px;font-size:.92rem}
.price{display:flex;flex-wrap:wrap;align-items:baseline;gap:4px 10px;margin:0!important}
.price .now{font-weight:700;font-size:1.05rem}
.price .old{font-size:.86rem;color:var(--text-secondary)}
.price .off{padding:1px 8px;border-radius:999px;border:1px solid var(--line-strong);color:var(--mint);font-family:var(--f-mono);font-size:.72rem}
.price .upd{flex-basis:100%;font-size:.76rem;color:var(--text-secondary)}

.end-cta{margin:clamp(56px,7vw,96px) auto 0;max-width:1180px;padding:clamp(28px,5vw,52px);border-radius:28px;background:linear-gradient(120deg,rgba(22,52,58,.95),rgba(22,52,58,.45));border:1px solid var(--line);display:flex;flex-wrap:wrap;gap:22px;justify-content:space-between;align-items:center}
.end-cta h2{font-size:clamp(1.9rem,3.6vw,3rem)}
.end-cta p{margin-top:8px;color:var(--text-secondary)}

footer{padding:56px clamp(20px,6vw,96px) 40px;border-top:1px solid var(--line);color:var(--text-secondary);font-size:.93rem}
footer .wrap{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.6fr);gap:32px}
footer p+p{margin-top:10px}
@media (max-width:760px){footer .wrap{grid-template-columns:1fr}}
@media (prefers-reduced-motion: reduce){
  *,*::before,*::after{animation:none!important;transition:none!important}
  .pulse path{stroke-dashoffset:0}
}