/* ==========================================================================
   NABD - EMS Continuous Learning Hub
   Design system: dark, teal, medical but friendly.
   ========================================================================== */

:root{
  --teal:#4BB5C8;
  --teal-soft:#7fd0de;
  --teal-dim:rgba(75,181,200,.14);
  --teal-line:rgba(75,181,200,.30);

  --bg:#0B1416;
  --bg-2:#0F1B1E;
  --surface:#122225;
  --surface-2:#16292D;
  --surface-3:#1C3338;
  --line:rgba(255,255,255,.08);
  --line-strong:rgba(255,255,255,.14);

  --text:#E8F1F2;
  --text-2:#A7BCC0;
  --text-3:#6F8A8F;

  --ok:#3FD08A;
  --ok-dim:rgba(63,208,138,.14);
  --warn:#F2B84B;
  --warn-dim:rgba(242,184,75,.14);
  --bad:#FF6B6B;
  --bad-dim:rgba(255,107,107,.14);

  --src-caroline:#B98CFF;
  --src-srca:#4BB5C8;
  --src-kfsh:#3FD08A;
  --src-moh:#F2B84B;

  --r-sm:10px; --r-md:16px; --r-lg:22px; --r-xl:28px;
  --shadow:0 18px 40px -18px rgba(0,0,0,.75);
  --tap:52px;

  --font:'Inter',system-ui,-apple-system,'Segoe UI',sans-serif;
  --font-ar:'IBM Plex Sans Arabic','Inter',system-ui,sans-serif;

  --safe-b:env(safe-area-inset-bottom,0px);
}

html[lang="ar"]{ --font:'IBM Plex Sans Arabic','Inter',system-ui,sans-serif; }

*{box-sizing:border-box;margin:0;padding:0}
html,body{height:100%}
body{
  background:
    radial-gradient(1100px 620px at 12% -8%, rgba(75,181,200,.13), transparent 60%),
    radial-gradient(900px 520px at 92% 4%, rgba(75,181,200,.07), transparent 55%),
    var(--bg);
  color:var(--text);
  font-family:var(--font);
  font-size:16px;
  line-height:1.55;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
  padding-bottom:calc(78px + var(--safe-b));
}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
svg.ico{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
input,select,textarea{font:inherit;color:inherit}
::selection{background:var(--teal);color:#04191d}

/* ---------- Splash ---------------------------------------------------- */
.splash{
  position:fixed;inset:0;z-index:999;display:grid;place-items:center;
  background:var(--bg);transition:opacity .5s ease,visibility .5s;
}
.splash.gone{opacity:0;visibility:hidden}
.splash-inner{text-align:center}
.splash-name{
  margin-top:10px;font-weight:800;letter-spacing:.42em;font-size:15px;
  color:var(--teal);text-indent:.42em;
  animation:fadeUp .8s .25s both;
}
.pulse-logo .ecg,.brand-mark .ecg{
  fill:none;stroke:var(--teal);stroke-width:2.6;stroke-linecap:round;stroke-linejoin:round;
}
.pulse-logo .ecg{
  stroke-dasharray:210;stroke-dashoffset:210;
  animation:draw 1.5s .1s ease forwards, glow 2s 1.4s ease-in-out infinite;
}
@keyframes draw{to{stroke-dashoffset:0}}
@keyframes glow{0%,100%{filter:drop-shadow(0 0 0 rgba(75,181,200,0))}50%{filter:drop-shadow(0 0 9px rgba(75,181,200,.75))}}
@keyframes fadeUp{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:none}}

/* ---------- Top bar ---------------------------------------------------- */
.topbar{
  position:sticky;top:0;z-index:50;
  display:flex;align-items:center;justify-content:space-between;gap:12px;
  padding:12px 16px;
  background:rgba(11,20,22,.82);
  backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);
  border-bottom:1px solid var(--line);
}
.brand{display:flex;align-items:center;gap:8px}
.brand-mark{width:44px;height:18px}
.brand-text{font-weight:800;letter-spacing:.22em;font-size:13px;color:var(--teal)}
.topbar-actions{display:flex;gap:8px}
.chip-btn{
  display:flex;align-items:center;gap:7px;
  padding:9px 14px;border-radius:999px;
  background:var(--surface-2);border:1px solid var(--line);
  font-size:13px;font-weight:600;color:var(--text-2);
  transition:.2s;min-height:40px;
}
.chip-btn:hover{border-color:var(--teal-line);color:var(--text)}
.chip-btn .ico{width:18px;height:18px}

/* ---------- Layout ----------------------------------------------------- */
.view{max-width:820px;margin:0 auto;padding:18px 16px 30px;animation:viewIn .35s ease}
@keyframes viewIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

.page-title{font-size:26px;font-weight:800;letter-spacing:-.02em;margin-bottom:4px}
.page-sub{color:var(--text-2);font-size:14.5px;margin-bottom:20px}
.section-title{
  font-size:12px;font-weight:700;letter-spacing:.16em;text-transform:uppercase;
  color:var(--text-3);margin:26px 0 12px;
}

/* ---------- Cards ------------------------------------------------------ */
.card{
  background:linear-gradient(180deg,var(--surface),var(--bg-2));
  border:1px solid var(--line);border-radius:var(--r-lg);
  padding:18px;box-shadow:var(--shadow);
}
.grid{display:grid;gap:12px}
.grid-2{grid-template-columns:repeat(2,1fr)}
@media(min-width:640px){.grid-3{grid-template-columns:repeat(3,1fr)}}

/* hero */
.hero{
  position:relative;overflow:hidden;
  background:linear-gradient(135deg,rgba(75,181,200,.20),rgba(75,181,200,.04) 55%,transparent),var(--surface);
  border:1px solid var(--teal-line);border-radius:var(--r-xl);
  padding:24px 22px;margin-bottom:8px;
}
.hero h1{font-size:24px;font-weight:800;letter-spacing:-.02em}
.hero p{color:var(--text-2);font-size:14.5px;margin-top:6px;max-width:44ch}
.hero-ecg{position:absolute;inset-inline-end:-10px;bottom:-6px;width:190px;opacity:.14}
.hero-ecg .ecg{stroke:var(--teal);stroke-width:3;fill:none}

/* stat tiles */
.stats{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-top:14px}
.stat{
  background:var(--surface-2);border:1px solid var(--line);border-radius:var(--r-md);
  padding:14px 12px;text-align:center;
}
.stat b{display:block;font-size:21px;font-weight:800;color:var(--teal)}
.stat span{font-size:11.5px;color:var(--text-3);letter-spacing:.04em}

/* action tiles */
.tiles{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin-top:16px}
.tile{
  display:flex;flex-direction:column;gap:8px;align-items:flex-start;text-align:start;
  background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);
  padding:18px 16px;min-height:118px;transition:.22s cubic-bezier(.2,.8,.3,1);
}
.tile:hover,.tile:active{transform:translateY(-3px);border-color:var(--teal-line);background:var(--surface-2)}
.tile .bubble{
  width:42px;height:42px;border-radius:13px;display:grid;place-items:center;
  background:var(--teal-dim);color:var(--teal);
}
.tile .bubble .ico{width:22px;height:22px}
.tile b{font-size:15.5px;font-weight:700}
.tile small{color:var(--text-3);font-size:12.5px;line-height:1.4}

/* ---------- Buttons ---------------------------------------------------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:9px;
  min-height:var(--tap);padding:0 22px;border-radius:14px;
  font-weight:700;font-size:15px;letter-spacing:.01em;
  background:var(--teal);color:#052026;border:1px solid transparent;
  transition:.2s;width:100%;
}
.btn:hover{background:var(--teal-soft);transform:translateY(-1px)}
.btn:active{transform:translateY(0) scale(.99)}
.btn.ghost{background:var(--surface-2);color:var(--text);border-color:var(--line-strong)}
.btn.ghost:hover{background:var(--surface-3);border-color:var(--teal-line)}
.btn.small{min-height:42px;font-size:13.5px;padding:0 16px;width:auto}
.btn.danger{background:var(--bad-dim);color:var(--bad);border-color:rgba(255,107,107,.3)}
.btn-row{display:flex;gap:10px;margin-top:14px}

/* ---------- Search ----------------------------------------------------- */
.searchwrap{position:sticky;top:64px;z-index:30;padding:6px 0 12px;background:linear-gradient(180deg,var(--bg) 70%,transparent)}
.searchbox{
  display:flex;align-items:center;gap:10px;
  background:var(--surface-2);border:1.5px solid var(--line-strong);
  border-radius:16px;padding:0 16px;min-height:58px;transition:.2s;
}
.searchbox:focus-within{border-color:var(--teal);box-shadow:0 0 0 4px var(--teal-dim)}
.searchbox .ico{color:var(--text-3);flex:none}
.searchbox input{background:none;border:0;outline:0;flex:1;font-size:16.5px;font-weight:500;min-width:0}
.searchbox input::placeholder{color:var(--text-3);font-weight:400}
.clearx{color:var(--text-3);font-size:20px;line-height:1;padding:6px}

.hotwords{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}
.hot{
  padding:9px 14px;border-radius:999px;font-size:13px;font-weight:600;
  background:var(--surface-2);border:1px solid var(--line);color:var(--text-2);transition:.18s;
}
.hot:hover{border-color:var(--teal-line);color:var(--teal);background:var(--teal-dim)}

/* ---------- Source badges --------------------------------------------- */
.src{
  display:inline-flex;align-items:center;gap:6px;
  padding:5px 11px;border-radius:999px;
  font-size:11.5px;font-weight:700;letter-spacing:.03em;white-space:nowrap;
}
.src::before{content:"";width:7px;height:7px;border-radius:50%;background:currentColor}
.src.caroline{color:var(--src-caroline);background:rgba(185,140,255,.13);border:1px solid rgba(185,140,255,.28)}
.src.srca{color:var(--src-srca);background:var(--teal-dim);border:1px solid var(--teal-line)}
.src.kfsh{color:var(--src-kfsh);background:var(--ok-dim);border:1px solid rgba(63,208,138,.28)}
.src.moh{color:var(--src-moh);background:var(--warn-dim);border:1px solid rgba(242,184,75,.28)}

/* ---------- Protocol result ------------------------------------------- */
.result{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);
  padding:16px;margin-bottom:12px;animation:viewIn .3s ease both;
}
.result-head{display:flex;align-items:flex-start;justify-content:space-between;gap:10px;margin-bottom:10px}
.result-head h3{font-size:17px;font-weight:700;line-height:1.3}
.steps{list-style:none;display:grid;gap:9px;margin-top:10px}
.steps li{display:flex;gap:11px;font-size:14.5px;color:var(--text-2);line-height:1.5}
.steps li::before{
  content:counter(s);counter-increment:s;
  flex:none;width:23px;height:23px;border-radius:8px;
  background:var(--teal-dim);color:var(--teal);
  font-size:11.5px;font-weight:800;display:grid;place-items:center;margin-top:1px;
}
.steps{counter-reset:s}

.dose{
  display:flex;justify-content:space-between;align-items:center;gap:12px;
  background:var(--surface-2);border:1px solid var(--line);
  border-radius:12px;padding:11px 14px;margin-top:8px;
}
.dose .k{font-size:13.5px;color:var(--text-2)}
.dose .v{font-size:15px;font-weight:800;color:var(--teal);text-align:end;font-variant-numeric:tabular-nums}

.cite{
  margin-top:12px;padding-top:11px;border-top:1px dashed var(--line-strong);
  font-size:12.5px;color:var(--text-3);display:flex;align-items:center;gap:7px;
}
.cite .ico{width:15px;height:15px;flex:none}

/* compare */
.compare{display:grid;gap:12px;margin-top:6px}
@media(min-width:700px){.compare.two{grid-template-columns:1fr 1fr}.compare.three{grid-template-columns:repeat(3,1fr)}}
.diffnote{
  background:var(--warn-dim);border:1px solid rgba(242,184,75,.3);color:var(--warn);
  border-radius:12px;padding:11px 14px;font-size:13.5px;font-weight:600;margin-bottom:12px;
  display:flex;gap:9px;align-items:flex-start;
}

/* ---------- Topic list ------------------------------------------------- */
.topic{
  display:flex;align-items:center;gap:14px;width:100%;text-align:start;
  background:var(--surface);border:1px solid var(--line);border-radius:var(--r-md);
  padding:15px 16px;transition:.2s;
}
.topic:hover{border-color:var(--teal-line);background:var(--surface-2);transform:translateX(2px)}
html[dir="rtl"] .topic:hover{transform:translateX(-2px)}
.topic .bubble{width:44px;height:44px;border-radius:14px;display:grid;place-items:center;background:var(--teal-dim);color:var(--teal);flex:none;font-size:20px}
.topic .meta{flex:1;min-width:0}
.topic .meta b{display:block;font-size:15.5px;font-weight:700}
.topic .meta small{color:var(--text-3);font-size:12.5px}
.topic .arrow{color:var(--text-3);flex:none}
html[dir="rtl"] .topic .arrow{transform:scaleX(-1)}

.bar{height:5px;border-radius:99px;background:var(--surface-3);overflow:hidden;margin-top:7px}
.bar i{display:block;height:100%;border-radius:99px;background:linear-gradient(90deg,var(--teal),var(--ok));transition:width .7s cubic-bezier(.2,.8,.3,1)}

/* ---------- Lesson ----------------------------------------------------- */
.lesson h2{font-size:22px;font-weight:800;margin-bottom:6px;letter-spacing:-.02em}
.lesson-block{margin-top:18px}
.lesson-block h4{
  font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--teal);
  margin-bottom:10px;font-weight:700;
}
.bullets{list-style:none;display:grid;gap:9px}
.bullets li{display:flex;gap:11px;font-size:14.8px;color:var(--text-2);line-height:1.55}
.bullets li::before{content:"";flex:none;width:6px;height:6px;border-radius:50%;background:var(--teal);margin-top:9px}
.redflags li::before{background:var(--bad)}
.pearls li::before{background:var(--warn)}

.numgrid{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:10px}
.num{background:var(--surface-2);border:1px solid var(--line);border-radius:14px;padding:13px}
.num .k{font-size:12px;color:var(--text-3);margin-bottom:3px}
.num .v{font-size:17px;font-weight:800;color:var(--teal);font-variant-numeric:tabular-nums}

/* ---------- Exam ------------------------------------------------------- */
.exam-top{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:14px}
.qcount{font-size:12.5px;color:var(--text-3);font-weight:600;letter-spacing:.06em}
.progline{height:6px;border-radius:99px;background:var(--surface-3);overflow:hidden;margin-bottom:20px}
.progline i{display:block;height:100%;background:linear-gradient(90deg,var(--teal),var(--teal-soft));transition:width .45s ease}

.qtext{font-size:19px;font-weight:700;line-height:1.45;margin-bottom:18px;letter-spacing:-.01em}
.opts{display:grid;gap:10px}
.opt{
  display:flex;align-items:center;gap:13px;text-align:start;width:100%;
  background:var(--surface);border:1.5px solid var(--line-strong);border-radius:15px;
  padding:15px 16px;min-height:var(--tap);font-size:15.5px;font-weight:500;
  transition:.18s;
}
.opt:hover:not(:disabled){border-color:var(--teal);background:var(--surface-2)}
.opt .k{
  flex:none;width:29px;height:29px;border-radius:9px;background:var(--surface-3);
  display:grid;place-items:center;font-size:13px;font-weight:800;color:var(--text-2);
}
.opt.right{border-color:var(--ok);background:var(--ok-dim)}
.opt.right .k{background:var(--ok);color:#04241a}
.opt.wrong{border-color:var(--bad);background:var(--bad-dim)}
.opt.wrong .k{background:var(--bad);color:#2a0505}
.opt:disabled{cursor:default;opacity:.85}
.opt.right,.opt.wrong{opacity:1}

.feedback{margin-top:16px;border-radius:var(--r-md);padding:16px;animation:fadeUp .3s ease both}
.feedback.ok{background:var(--ok-dim);border:1px solid rgba(63,208,138,.3)}
.feedback.no{background:var(--bad-dim);border:1px solid rgba(255,107,107,.3)}
.feedback .fb-title{display:flex;align-items:center;gap:9px;font-weight:800;font-size:15.5px;margin-bottom:8px}
.feedback.ok .fb-title{color:var(--ok)}
.feedback.no .fb-title{color:var(--bad)}
.feedback p{font-size:14.5px;color:var(--text-2);line-height:1.6}

.review-box{
  margin-top:13px;background:rgba(0,0,0,.24);border:1px solid var(--line);
  border-radius:14px;padding:14px;
}
.review-box h5{font-size:11.5px;letter-spacing:.14em;text-transform:uppercase;color:var(--teal);margin-bottom:9px}
.review-box .bullets li{font-size:14px}

/* result screen */
.score-ring{width:168px;height:168px;margin:6px auto 18px;position:relative}
.score-ring svg{transform:rotate(-90deg)}
.score-ring .track{fill:none;stroke:var(--surface-3);stroke-width:12}
.score-ring .val{fill:none;stroke:var(--teal);stroke-width:12;stroke-linecap:round;transition:stroke-dashoffset 1.1s cubic-bezier(.2,.8,.3,1)}
.score-ring .mid{position:absolute;inset:0;display:grid;place-content:center;text-align:center}
.score-ring .mid b{font-size:40px;font-weight:800;line-height:1}
.score-ring .mid span{font-size:12px;color:var(--text-3);letter-spacing:.1em}

/* ---------- Game ------------------------------------------------------- */
.letters{display:grid;grid-template-columns:repeat(auto-fit,minmax(58px,1fr));gap:10px;margin-top:16px}
.lt{
  aspect-ratio:1;border-radius:16px;display:grid;place-items:center;
  background:var(--surface-2);border:1.5px solid var(--line-strong);
  font-size:24px;font-weight:800;font-family:var(--font-ar);
  transition:.2s cubic-bezier(.2,.8,.3,1);
}
.lt:hover:not(:disabled){transform:translateY(-3px) scale(1.04);border-color:var(--teal);color:var(--teal)}
.lt.done-ok{background:var(--ok-dim);border-color:var(--ok);color:var(--ok)}
.lt.done-no{background:var(--bad-dim);border-color:var(--bad);color:var(--bad)}
.lt:disabled{cursor:default}

.teams{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:6px}
.team{background:var(--surface);border:1.5px solid var(--line);border-radius:var(--r-md);padding:14px;text-align:center;transition:.2s}
.team.active{border-color:var(--teal);background:var(--teal-dim);box-shadow:0 0 0 3px var(--teal-dim)}
.team .nm{font-size:12.5px;color:var(--text-3);letter-spacing:.08em;text-transform:uppercase;font-weight:700}
.team .sc{font-size:32px;font-weight:800;color:var(--teal);line-height:1.1}

/* ---------- Reference cards ------------------------------------------- */
.refcard{
  background:linear-gradient(160deg,var(--surface-2),var(--bg-2));
  border:1px solid var(--teal-line);border-radius:var(--r-lg);
  padding:18px;margin-bottom:12px;
}
.refcard h3{font-size:17px;font-weight:800;margin-bottom:3px}
.refcard .sub{font-size:12.5px;color:var(--text-3);margin-bottom:13px}
table.ref{width:100%;border-collapse:collapse;font-size:14px}
table.ref th{
  text-align:start;font-size:11px;letter-spacing:.1em;text-transform:uppercase;
  color:var(--text-3);padding:8px 10px;border-bottom:1px solid var(--line-strong);font-weight:700;
}
table.ref td{padding:10px;border-bottom:1px solid var(--line);color:var(--text-2)}
table.ref td:first-child{font-weight:600;color:var(--text)}
table.ref td.v{color:var(--teal);font-weight:700;font-variant-numeric:tabular-nums;white-space:nowrap}
table.ref tr:last-child td{border-bottom:0}
.tablescroll{overflow-x:auto;-webkit-overflow-scrolling:touch}

/* ---------- Misc ------------------------------------------------------- */
.empty{text-align:center;padding:50px 20px;color:var(--text-3)}
.empty .big{font-size:44px;margin-bottom:12px;opacity:.5}
.back{
  display:inline-flex;align-items:center;gap:7px;color:var(--text-3);
  font-size:13.5px;font-weight:600;margin-bottom:14px;padding:8px 0;
}
.back:hover{color:var(--teal)}
html[dir="rtl"] .back .ico{transform:scaleX(-1)}

.notice{
  background:var(--teal-dim);border:1px solid var(--teal-line);border-radius:14px;
  padding:13px 15px;font-size:13.5px;color:var(--text-2);line-height:1.55;
  display:flex;gap:10px;align-items:flex-start;margin-bottom:16px;
}
.notice .ico{color:var(--teal);flex:none;width:19px;height:19px;margin-top:1px}

.pill{
  display:inline-block;padding:4px 10px;border-radius:999px;font-size:11px;font-weight:700;
  background:var(--surface-3);color:var(--text-3);letter-spacing:.04em;
}
.pill.ok{background:var(--ok-dim);color:var(--ok)}
.pill.warn{background:var(--warn-dim);color:var(--warn)}

/* ---------- Bottom tab bar -------------------------------------------- */
.tabbar{
  position:fixed;inset-inline:0;bottom:0;z-index:60;
  display:grid;grid-template-columns:repeat(6,1fr);
  gap:2px;padding:8px 6px calc(8px + var(--safe-b));
  background:rgba(15,27,30,.92);
  backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px);
  border-top:1px solid var(--line);
}
.tab{
  display:flex;flex-direction:column;align-items:center;gap:4px;
  padding:7px 2px;border-radius:13px;color:var(--text-3);
  font-size:10.5px;font-weight:600;transition:.18s;
}
.tab .ico{width:21px;height:21px}
.tab.on{color:var(--teal);background:var(--teal-dim)}
.tab:hover{color:var(--text-2)}

/* ---------- Sheet ------------------------------------------------------ */
.sheet{position:fixed;inset:0;z-index:200;display:flex;align-items:flex-end;justify-content:center}
.sheet[hidden],.toast[hidden]{display:none}
.sheet-backdrop{position:absolute;inset:0;background:rgba(0,0,0,.6);backdrop-filter:blur(3px);animation:fadeIn .25s ease}
.sheet-body{
  position:relative;width:100%;max-width:520px;max-height:82vh;overflow-y:auto;
  background:var(--surface);border:1px solid var(--line-strong);
  border-radius:var(--r-xl) var(--r-xl) 0 0;padding:22px 18px calc(26px + var(--safe-b));
  animation:slideUp .3s cubic-bezier(.2,.8,.3,1);
}
@keyframes fadeIn{from{opacity:0}to{opacity:1}}
@keyframes slideUp{from{transform:translateY(100%)}to{transform:none}}
.sheet-body h3{font-size:19px;font-weight:800;margin-bottom:14px}
.field{margin-bottom:13px}
.field label{display:block;font-size:12.5px;color:var(--text-3);margin-bottom:6px;font-weight:600}
.field input,.field select{
  width:100%;background:var(--surface-2);border:1.5px solid var(--line-strong);
  border-radius:13px;padding:14px 15px;font-size:15.5px;outline:0;transition:.2s;
}
.field input:focus,.field select:focus{border-color:var(--teal);box-shadow:0 0 0 3px var(--teal-dim)}

/* ---------- Toast ------------------------------------------------------ */
.toast{
  position:fixed;bottom:calc(92px + var(--safe-b));inset-inline:0;margin:auto;
  width:max-content;max-width:88%;z-index:300;
  background:var(--surface-3);border:1px solid var(--teal-line);
  border-radius:999px;padding:12px 20px;font-size:14px;font-weight:600;
  box-shadow:var(--shadow);animation:fadeUp .25s ease;
}

/* ---------- Desktop ---------------------------------------------------- */
@media(min-width:900px){
  body{padding-bottom:0}
  .tabbar{
    inset-inline:auto;inset-inline-start:0;top:0;bottom:0;
    grid-template-columns:1fr;grid-auto-rows:max-content;
    width:96px;padding:88px 12px 12px;gap:6px;
    border-top:0;border-inline-end:1px solid var(--line);
  }
  .tab{padding:13px 6px;font-size:11px}
  .view{margin-inline-start:96px;padding-top:26px}
  .topbar{padding-inline-start:112px}
}

@media(prefers-reduced-motion:reduce){
  *{animation-duration:.01ms!important;transition-duration:.01ms!important}
}

/* ---------- Signature ------------------------------------------------- */
.sig{
  display:flex;justify-content:flex-end;margin:34px 4px 6px;
}
html[dir="rtl"] .sig{justify-content:flex-start}
.sig-inner{
  display:inline-flex;flex-direction:column;align-items:center;gap:2px;
  padding:8px 16px 10px;border-radius:14px;
  background:var(--surface);border:1px solid var(--line);
  opacity:.85;transition:.25s;
}
.sig-inner:hover{opacity:1;border-color:var(--teal-line)}
.sig-name{
  font-family:'Great Vibes','Inter',cursive;
  font-size:21px;line-height:1.1;color:var(--teal);
  letter-spacing:.02em;
}
.sig-line{width:100%;max-width:110px}
.sig-line path{fill:none;stroke:var(--teal);stroke-width:1.6;stroke-linecap:round;opacity:.7}

/* ---------- Deep lesson checkpoints ----------------------------------- */
.cp{background:var(--surface);border:1.5px solid var(--teal-line);border-radius:var(--r-md);padding:16px;margin-top:18px;animation:fadeUp .3s ease}
.cp h5{font-size:11.5px;letter-spacing:.14em;text-transform:uppercase;color:var(--teal);margin-bottom:10px}
.cp .qtext{font-size:16px;margin-bottom:12px}
.cp.shake{animation:shakeX .4s ease}
@keyframes shakeX{0%,100%{transform:none}25%{transform:translateX(-6px)}75%{transform:translateX(6px)}}
.cp-done{display:flex;align-items:center;gap:10px;background:var(--ok-dim);border:1px solid rgba(63,208,138,.3);border-radius:12px;padding:12px 14px;color:var(--ok);font-weight:700;font-size:14px;margin-top:14px}
.flagbtn{display:block;width:100%;text-align:start;background:var(--surface-2);border:1.5px solid var(--line-strong);border-radius:12px;padding:12px 14px;margin-top:8px;font-size:14px;transition:.15s}
.flagbtn.sel{border-color:var(--warn);background:var(--warn-dim)}
.flagbtn.hit{border-color:var(--bad);background:var(--bad-dim);color:var(--bad)}
.flagbtn.safe{opacity:.55}
.term{background:var(--surface-2);border:1px solid var(--line);border-radius:12px;padding:11px 14px;margin-top:8px}
.term b{color:var(--teal);font-size:14px}
.term div{color:var(--text-2);font-size:13.5px;margin-top:2px}
.noselect{-webkit-user-select:none;user-select:none}

/* ---------- Locked-preview tiles + guide ------------------------------ */
.tile{position:relative}
.tile-lock{
  position:absolute;top:10px;inset-inline-end:10px;
  font-size:13px;background:var(--surface-3);border:1px solid var(--line-strong);
  border-radius:999px;padding:3px 8px;line-height:1;
}
.tile.locked{opacity:.6}
.tile.locked:hover{transform:none;border-color:var(--line)}
.guide-dot{width:7px;height:7px;border-radius:50%;background:var(--surface-3);transition:.2s}
.guide-dot.on{background:var(--teal);width:20px;border-radius:99px}

/* ---------- Embedded video ------------------------------------------- */
.videowrap{position:relative;width:100%;aspect-ratio:16/9;border-radius:var(--r-md);overflow:hidden;border:1px solid var(--line-strong);background:#000}
.videowrap iframe{position:absolute;inset:0;width:100%;height:100%;border:0}