/* ============================================================
   GRAYNEURA — Hệ giao diện (dark / neural)
   Dùng chung cho PREVIEW và plugin WordPress.
   ============================================================ */
/* Quiet Ascent — dark editorial study system. Tokens: DESIGN.md */
:root{
  --bg:#121319; --bg2:#0e0f15;
  --surface:#191B23; --surface2:#21242E; --surface3:#2A2D39;
  --line:rgba(236,237,244,.08); --line2:rgba(236,237,244,.15);
  --ink:#ECEDF4; --ink2:#c2c5d4; --muted:#9499AC; --faint:#6f7488;
  --accent:#7C88E6; --accent-ink:#9AA4F2; --accent-soft:rgba(124,136,230,.13);
  --ok:#5BB98B; --ok-soft:rgba(91,185,139,.12);
  --bad:#E0696B;
  --r:12px; --r-lg:18px; --r-sm:8px;
  --maxw:1080px;
  --shadow:0 16px 44px rgba(8,9,16,.55);
  --ring:0 0 0 3px rgba(124,136,230,.35);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
html,body{margin:0;padding:0}
body{
  background:var(--bg); color:var(--ink);
  font-family:'Be Vietnam Pro',system-ui,sans-serif;
  font-size:15px; line-height:1.65; -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
body.gn-loading{opacity:0}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
h1,h2,h3,h4,p{margin:0}
em{font-style:italic;color:var(--accent-ink)}
::selection{background:var(--accent-soft);color:#fff}
:focus-visible{outline:none;box-shadow:var(--ring);border-radius:6px}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 22px}
.disp{font-family:'Fraunces','Be Vietnam Pro',Georgia,serif;font-variation-settings:'opsz' 80;letter-spacing:-.015em}

/* ---------- NAV ---------- */
.gn-nav{position:sticky;top:0;z-index:40;background:rgba(13,14,19,.82);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.gn-nav .wrap{display:flex;align-items:center;gap:16px;height:62px}
.gn-logo{display:flex;align-items:center;gap:9px;font-weight:600;font-size:19px;color:#fff;font-family:'Fraunces',serif;letter-spacing:-.01em}
.gn-mark{width:26px;height:26px;border-radius:7px;background:var(--accent);display:flex;align-items:center;justify-content:center;color:#fff;font-size:15px}
.gn-menu{display:flex;gap:4px;margin-left:6px}
.gn-menu a{padding:8px 13px;border-radius:8px;font-size:13.5px;color:var(--ink2);transition:background .2s,color .2s}
.gn-menu a:hover{background:var(--surface2);color:#fff}
.gn-menu a.active{color:#fff;background:var(--surface2);box-shadow:inset 0 -2px 0 var(--accent)}
.gn-nav .spacer{flex:1}
.gn-userchip{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--ink2);background:var(--surface);border:1px solid var(--line);padding:6px 12px;border-radius:99px}
.gn-userchip .av{width:22px;height:22px;border-radius:50%;background:var(--accent-soft);color:var(--accent-ink);display:flex;align-items:center;justify-content:center;font-size:11px;font-weight:600}
.btn{display:inline-flex;align-items:center;gap:7px;border:none;cursor:pointer;font-family:inherit;font-weight:600;font-size:13.5px;padding:11px 18px;border-radius:var(--r);transition:background .2s,transform .2s,box-shadow .2s,border-color .2s;line-height:1}
.btn-primary{background:var(--accent);color:#15161C}
.btn-primary:hover{background:var(--accent-ink);transform:translateY(-1px)}
.btn-primary:active{transform:scale(.98)}
.btn-ghost{background:transparent;color:var(--ink);border:1px solid var(--line2)}
.btn-ghost:hover{background:var(--surface2);border-color:var(--muted)}
.btn-ghost:active{transform:scale(.98)}
.btn-sm{padding:9px 14px;font-size:12.5px;border-radius:var(--r-sm)}
.btn:disabled{opacity:.45;cursor:not-allowed;transform:none}

/* ---------- HERO ---------- */
.hero{position:relative;overflow:hidden;padding:78px 0 60px}
.hero .wrap{position:relative;z-index:2;max-width:760px}
.eyebrow{display:inline-flex;align-items:center;gap:7px;font-size:12px;font-weight:600;letter-spacing:.04em;color:var(--accent-ink);border:1px solid var(--line2);background:var(--accent-soft);padding:6px 13px;border-radius:99px;margin-bottom:22px}
.hero h1{font-size:clamp(36px,6vw,58px);font-weight:600;letter-spacing:-.02em;line-height:1.05;text-wrap:balance}
.hero .sub{color:var(--ink2);font-size:clamp(15px,2vw,18px);margin-top:18px;max-width:560px}
.hero .cta{display:flex;gap:12px;margin-top:28px;flex-wrap:wrap}
.hero .btn{padding:13px 22px;font-size:15px}
.stats{display:flex;gap:26px;margin-top:34px;flex-wrap:wrap;font-size:13px;color:var(--faint)}
.stats b{color:#fff;font-weight:600}
.neural-bg{position:absolute;inset:0;z-index:1;opacity:.5;pointer-events:none}

/* ---------- SECTION ---------- */
.section{padding:56px 0}
.section-head{margin-bottom:30px}
.kicker{font-size:12px;font-weight:600;letter-spacing:.14em;text-transform:uppercase;color:var(--muted);margin-bottom:10px}
.section-head h2{font-size:clamp(23px,3vw,32px);font-weight:600;color:#fff;letter-spacing:-.015em;line-height:1.12;text-wrap:balance}
.section-head p{color:var(--muted);margin-top:8px;max-width:600px}

/* ---------- LEARNING LOOP ---------- */
.loop{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.loop .step{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);padding:22px 20px;position:relative;transition:border-color .2s,transform .2s}
.loop .step:hover{border-color:var(--line2);transform:translateY(-2px)}
.loop .step .n{font-family:'Fraunces',serif;font-weight:600;font-size:15px;color:var(--accent-ink)}
.loop .step .ic{width:42px;height:42px;border-radius:11px;background:var(--accent-soft);display:flex;align-items:center;justify-content:center;color:var(--accent-ink);font-size:21px;margin:12px 0 12px}
.loop .step h3{font-size:15.5px;color:#fff;font-weight:600}
.loop .step p{font-size:13px;color:var(--muted);margin-top:5px}

/* ---------- COURSE GRID ---------- */
.grid{display:grid;gap:16px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);padding:22px;transition:border-color .2s,transform .2s,box-shadow .2s;cursor:pointer;display:block}
.card:hover{border-color:var(--line2);transform:translateY(-2px);box-shadow:var(--shadow)}
.card:active{transform:translateY(0)}
.course-head{display:flex;align-items:center;gap:13px;margin-bottom:14px}
.course-ic{width:46px;height:46px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:23px;flex:none}
.course-head h3{font-size:18px;color:#fff;font-weight:600}
.course-head .meta{font-size:12.5px;color:var(--muted)}
.course-foot{display:flex;align-items:center;justify-content:space-between;margin-top:16px;gap:12px}
.prog{flex:1}
.prog .lbl{display:flex;justify-content:space-between;font-size:11.5px;color:var(--faint);margin-bottom:5px}
.bar{height:7px;border-radius:99px;background:var(--surface3);overflow:hidden}
.bar i{display:block;height:100%;border-radius:99px;background:var(--accent);transition:width .5s}
.badge{font-size:11px;padding:3px 9px;border-radius:99px;background:var(--surface2);color:var(--ink2);border:1px solid var(--line)}
.chip{font-size:11px;padding:3px 9px;border-radius:6px;background:var(--accent-soft);color:var(--accent-ink);font-weight:500}

/* ---------- BREADCRUMB / BACK ---------- */
.crumb{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--muted);margin-bottom:18px;cursor:pointer;width:max-content}
.crumb:hover{color:#fff}

/* ---------- LESSON LIST ---------- */
.lesson-row{display:flex;align-items:center;gap:14px;background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:15px 17px;margin-bottom:10px;cursor:pointer;transition:.15s}
.lesson-row:hover{border-color:var(--line2);background:var(--surface2)}
.lesson-row .ix{width:30px;height:30px;border-radius:8px;background:var(--surface2);display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:600;color:var(--muted);flex:none}
.lesson-row.done .ix{background:rgba(61,220,151,.16);color:var(--ok)}
.lesson-row .info{flex:1}
.lesson-row .info h4{font-size:15px;color:#fff;font-weight:500}
.lesson-row .info .m{font-size:12px;color:var(--muted)}
.lesson-row .stat{font-size:12px;color:var(--faint)}
.lesson-row .stat.ok{color:var(--ok)}

/* ---------- LESSON READER ---------- */
.reader{max-width:720px}
.reader .ttl{font-size:clamp(24px,4vw,34px);font-weight:700;color:#fff;letter-spacing:-.5px;line-height:1.15}
.reader .meta{display:flex;gap:14px;color:var(--muted);font-size:13px;margin:14px 0 26px}
.prose{color:var(--ink2);font-size:16px;line-height:1.8}
.prose p{margin:0 0 16px}
.prose h3{color:#fff;font-size:19px;font-weight:600;margin:28px 0 12px}
.prose ul{margin:0 0 16px;padding-left:22px}
.prose li{margin:0 0 8px}
.prose strong{color:var(--ink);font-weight:600}
.prose blockquote{margin:20px 0;padding:14px 18px;border-left:3px solid var(--accent);background:var(--accent-soft);border-radius:0 var(--r) var(--r) 0;color:var(--ink)}

/* step nav inside lesson */
.lesson-steps{display:flex;gap:8px;margin:30px 0 24px}
.lesson-steps .s{flex:1;height:4px;border-radius:99px;background:var(--surface3)}
.lesson-steps .s.active{background:var(--accent)}
.lesson-steps .s.done{background:var(--ok)}

.panel{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);padding:26px;margin-top:8px}
.panel-head{display:flex;align-items:center;gap:11px;margin-bottom:6px}
.panel-head .pic{width:38px;height:38px;border-radius:10px;background:var(--accent-soft);color:var(--accent-ink);display:flex;align-items:center;justify-content:center;font-size:19px}
.panel-head h3{font-size:19px;color:#fff;font-weight:600}
.panel-head p{font-size:13px;color:var(--muted)}

/* ---------- QUIZ ---------- */
.q{margin:22px 0;padding-bottom:22px;border-bottom:1px solid var(--line)}
.q:last-of-type{border-bottom:none}
.q .qt{font-size:16px;color:#fff;font-weight:500;margin-bottom:13px}
.q .qt .num{color:var(--accent-ink);font-weight:600;margin-right:6px}
.opt{display:flex;align-items:center;gap:12px;padding:12px 15px;border:1px solid var(--line);border-radius:var(--r);margin-bottom:9px;cursor:pointer;transition:.13s;color:var(--ink2)}
.opt:hover{border-color:var(--line2);background:var(--surface2)}
.opt .dot{width:20px;height:20px;border-radius:50%;border:2px solid var(--muted);flex:none;display:flex;align-items:center;justify-content:center;transition:.13s}
.opt.sel{border-color:var(--accent);background:var(--accent-soft);color:#fff}
.opt.sel .dot{border-color:var(--accent);background:var(--accent)}
.opt.sel .dot::after{content:"";width:7px;height:7px;border-radius:50%;background:#fff}
.opt.correct{border-color:var(--ok);background:rgba(61,220,151,.1);color:#fff}
.opt.correct .dot{border-color:var(--ok);background:var(--ok)}
.opt.wrong{border-color:var(--bad);background:rgba(255,107,107,.1);color:#fff}
.opt.wrong .dot{border-color:var(--bad);background:var(--bad)}
.opt.locked{cursor:default;pointer-events:none}
.explain{font-size:13px;color:var(--muted);margin-top:8px;padding-left:2px;display:flex;gap:7px}
.explain i{color:var(--accent-ink);margin-top:2px}

/* quiz result */
.result{text-align:center;padding:14px 0 4px}
.score-ring{width:130px;height:130px;margin:0 auto 16px;position:relative}
.score-ring .val{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center}
.score-ring .val .pct{font-size:36px;font-weight:600;color:#fff;font-family:'Fraunces',serif;letter-spacing:-.02em;line-height:1}
.score-ring .val .sub{font-size:11px;color:var(--muted);margin-top:3px}
.result h3{font-size:22px;color:#fff;font-weight:700;margin-bottom:6px}
.result .msg{color:var(--ink2);max-width:420px;margin:0 auto 18px}
.result.pass h3{color:var(--ok)}
.result.fail h3{color:var(--accent-ink)}

/* ---------- GOAL BUILDER ---------- */
.goal-input{width:100%;background:var(--bg);border:1px solid var(--line2);border-radius:var(--r);color:var(--ink);font-family:inherit;font-size:15px;padding:13px 15px;resize:vertical;min-height:54px}
.goal-input:focus{outline:none;border-color:var(--accent)}
.goal-suggest{display:flex;flex-wrap:wrap;gap:8px;margin:12px 0 4px}
.sg{font-size:12.5px;color:var(--ink2);background:var(--surface2);border:1px dashed var(--line2);padding:7px 12px;border-radius:99px;cursor:pointer;transition:.13s}
.sg:hover{border-color:var(--accent);color:#fff;border-style:solid}
.sg i{color:var(--accent-ink);margin-right:4px}
.addrow{display:flex;gap:9px;margin-top:14px}
.addrow input{flex:1;background:var(--bg);border:1px solid var(--line2);border-radius:var(--r);color:var(--ink);font-family:inherit;font-size:14px;padding:11px 14px}
.addrow input:focus{outline:none;border-color:var(--accent)}

.checklist{margin-top:18px;display:flex;flex-direction:column;gap:9px}
.task{display:flex;align-items:center;gap:13px;background:var(--surface2);border:1px solid var(--line);border-radius:var(--r);padding:13px 15px;transition:.15s}
.task .box{width:22px;height:22px;border-radius:7px;border:2px solid var(--muted);flex:none;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:.13s;color:transparent;font-size:13px}
.task.done .box{background:var(--accent);border-color:var(--accent);color:#15161C}
.task .tx{flex:1;font-size:14.5px;color:var(--ink)}
.task.done .tx{color:var(--muted);text-decoration:line-through}
.task .del{color:var(--faint);cursor:pointer;opacity:0;transition:.13s;font-size:16px}
.task:hover .del{opacity:1}
.task .del:hover{color:var(--bad)}

.goal-prog{display:flex;align-items:center;gap:14px;margin-top:18px;padding:15px 17px;background:var(--surface2);border-radius:var(--r);border:1px solid var(--line)}
.goal-prog .ring{width:46px;height:46px;flex:none}
.goal-prog .txt{flex:1}
.goal-prog .txt b{color:#fff;font-weight:600}
.goal-prog .txt .s{font-size:12.5px;color:var(--muted)}
.goal-prog.complete{border-color:rgba(91,185,139,.35);background:var(--ok-soft)}

.celebrate{text-align:center;padding:20px;border:1px solid rgba(91,185,139,.3);background:var(--ok-soft);border-radius:var(--r-lg);margin-top:18px}
.celebrate .big{font-size:17px;color:#fff;font-weight:600;font-family:'Fraunces',serif;letter-spacing:-.01em}
.celebrate .big i{color:var(--ok)}
.celebrate .s{font-size:13px;color:var(--ink2);margin-top:4px}

/* ---------- APPS ---------- */
.app-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);overflow:hidden;transition:.18s}
.app-card:hover{border-color:var(--line2);transform:translateY(-2px)}
.app-thumb{height:150px;background:var(--surface2);display:flex;align-items:center;justify-content:center;color:#3a3f56;font-size:42px;position:relative;border-bottom:1px solid var(--line)}
.app-thumb img{width:100%;height:100%;object-fit:cover}
.app-thumb .gif-tag{position:absolute;top:10px;left:10px;font-size:10px;font-weight:600;color:var(--ink2);background:var(--surface3);border:1px solid var(--line2);padding:3px 8px;border-radius:6px;letter-spacing:.5px}
.app-body{padding:16px 17px}
.app-body h3{font-size:16px;color:#fff;font-weight:600}
.app-body p{font-size:13px;color:var(--muted);margin-top:5px;min-height:38px}
.app-tags{display:flex;gap:6px;margin:10px 0 14px;flex-wrap:wrap}

/* ---------- AUTH MODAL ---------- */
.modal-veil{position:absolute;inset:0;background:rgba(5,6,10,.7);display:flex;align-items:center;justify-content:center;z-index:80;padding:20px}
.modal{background:var(--surface);border:1px solid var(--line2);border-radius:var(--r-lg);padding:28px;max-width:380px;width:100%;box-shadow:var(--shadow)}
.modal h3{font-size:20px;color:#fff;font-weight:700;text-align:center}
.modal p{color:var(--muted);font-size:13.5px;text-align:center;margin:6px 0 20px}
.modal label{font-size:12.5px;color:var(--ink2);display:block;margin:0 0 6px}
.modal input{width:100%;background:var(--bg);border:1px solid var(--line2);border-radius:var(--r);color:var(--ink);font-family:inherit;font-size:15px;padding:12px 14px;margin-bottom:14px}
.modal input:focus{outline:none;border-color:var(--accent)}
.modal .btn{width:100%;justify-content:center;padding:13px}

/* ---------- FOOTER ---------- */
.gn-foot{border-top:1px solid var(--line);margin-top:40px;padding:30px 0 40px}
.gn-foot .wrap{display:flex;align-items:center;justify-content:space-between;gap:14px;flex-wrap:wrap}
.gn-foot .motto{font-size:17px;color:#fff;font-weight:500;font-family:'Fraunces',serif;letter-spacing:-.01em;font-style:italic}
.gn-foot .c{font-size:12.5px;color:var(--faint)}

/* ---------- TOAST ---------- */
.toast{position:absolute;left:50%;bottom:24px;transform:translateX(-50%) translateY(20px);background:var(--surface2);border:1px solid var(--line2);color:#fff;font-size:13.5px;padding:11px 18px;border-radius:99px;z-index:90;opacity:0;transition:.25s;display:flex;align-items:center;gap:8px;box-shadow:var(--shadow)}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}
.toast i{color:var(--accent-ink)}

/* ---------- RESPONSIVE ---------- */
@media(max-width:820px){
  .loop{grid-template-columns:repeat(2,1fr)}
  .grid-2,.grid-3{grid-template-columns:1fr}
  .gn-menu{display:none}
}
@media(max-width:520px){
  .loop{grid-template-columns:1fr}
  .stats{gap:16px}
  .gn-nav .wrap{gap:10px}
}

.fade{animation:fade .35s ease}
@keyframes fade{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);border:0}
.skip-link:focus{position:fixed;top:12px;left:12px;width:auto;height:auto;clip:auto;margin:0;padding:10px 16px;z-index:200;background:var(--surface2);border:1px solid var(--accent);border-radius:var(--r);color:#fff;box-shadow:var(--shadow)}
@media(prefers-reduced-motion:reduce){
  *{animation-duration:.001ms!important;transition-duration:.001ms!important;scroll-behavior:auto!important}
}