/* ============ SwipeScript AI — design system (light spring theme) ============ */
:root{
  --bg:#e8f5e9; --bg2:#ffffff; --panel:#ffffff;
  --line:rgba(53,88,52,.14);
  --text:#22332a; --muted:#6a7d6c; --dim:#9aab9c;
  --python:#f59e0b; --genai:#65a30d; --agentic:#0d9488; --mcp:#ca8a04;
  --python-deep:#b45309; --genai-deep:#4d7c0f; --agentic-deep:#0f766e; --mcp-deep:#a16207;
  --ok:#16a34a; --danger:#dc2626;
  --rail:64px;
  --sat:env(safe-area-inset-top,0px); --sab:env(safe-area-inset-bottom,0px);
}
*{margin:0;padding:0;box-sizing:border-box;-webkit-tap-highlight-color:transparent}
::selection{background:#ffe082}
html,body{height:100%}
body{
  background:var(--bg); color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"SF Pro Rounded","Segoe UI",Roboto,Inter,system-ui,sans-serif;
  overflow:hidden; user-select:none; -webkit-user-select:none; overscroll-behavior:none;
}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
#app{height:100vh;height:100dvh;display:flex;flex-direction:column;position:relative;overflow:hidden}

/* ---------- top bar ---------- */
#topbar{
  position:absolute;z-index:40;inset-inline:0;top:0;padding:calc(10px + var(--sat)) 14px 10px;
  display:flex;align-items:center;gap:10px;
  background:linear-gradient(rgba(255,255,255,.92),transparent);
}
.brand{font-weight:900;font-size:20px;letter-spacing:-.5px;color:var(--text)}
.brand span{background:linear-gradient(90deg,#65a30d,#f59e0b);-webkit-background-clip:text;background-clip:text;color:transparent;margin-left:2px}
.streak{margin-left:auto;font-size:13px;background:rgba(255,255,255,.9);border:1px solid var(--line);padding:4px 10px;border-radius:999px;font-weight:700;color:var(--text)}
.streak b{margin-left:3px}
.iconbtn{width:36px;height:36px;border-radius:50%;display:grid;place-items:center;background:rgba(255,255,255,.92);border:1px solid var(--line);font-size:16px;box-shadow:0 2px 10px rgba(53,88,52,.1)}
.iconbtn:active{transform:scale(.92)}
.set-row .iconbtn{flex:none;cursor:pointer}
.set-row select{flex:1;min-width:0}

/* ---------- feeds ---------- */
#feeds{flex:1;position:relative}
.feed{position:absolute;inset:0;overflow-y:auto;overflow-x:hidden;scroll-snap-type:y mandatory;scroll-behavior:smooth;display:none;overscroll-behavior:contain;scrollbar-width:none}
.feed::-webkit-scrollbar{display:none}
.feed.active{display:block}

/* ---------- reel ---------- */
.reel{
  height:100%;scroll-snap-align:start;scroll-snap-stop:always;position:relative;overflow:hidden;touch-action:pan-y;
  display:flex;flex-direction:column;
  --accent:var(--genai);--accent-deep:var(--genai-deep);--accent-soft:rgba(101,163,13,.13);
}
.reel[data-section=python]{--accent:var(--python);--accent-deep:var(--python-deep);--accent-soft:rgba(245,158,11,.14)}
.reel[data-section=genai]{--accent:var(--genai);--accent-deep:var(--genai-deep);--accent-soft:rgba(101,163,13,.13)}
.reel[data-section=agentic]{--accent:var(--agentic);--accent-deep:var(--agentic-deep);--accent-soft:rgba(13,148,136,.12)}
.reel-inner{position:absolute;inset:0;display:flex;flex-direction:column}
.reel-bg{position:absolute;inset:0;pointer-events:none;
  background:
    radial-gradient(120% 60% at 50% -10%,var(--accent-soft),transparent 62%),
    radial-gradient(90% 50% at 85% 110%,var(--accent-soft),transparent 60%),
    linear-gradient(rgba(53,88,52,.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(53,88,52,.05) 1px,transparent 1px);
  background-size:auto,auto,44px 44px,44px 44px;
}

/* progress segments */
.segs{position:relative;z-index:6;display:flex;gap:4px;padding:calc(52px + var(--sat)) 12px 0}
.seg{flex:1;height:3px;border-radius:3px;background:rgba(53,88,52,.16);overflow:hidden}
.seg b{display:block;height:100%;width:0;background:var(--accent);border-radius:3px}
.seg.done b{width:100%}
.seg.live b{transition:width .3s linear}

/* stage */
.stage{position:relative;z-index:2;flex:1;display:flex;align-items:center;justify-content:center;padding:8px 18px 150px;min-height:0}
.stage.frozen,.stage.frozen *{animation-play-state:paused!important}
.scene{position:absolute;inset:8px 18px 150px;display:flex;align-items:center;justify-content:center;text-align:center}

/* ---------- caption zone ---------- */
.capzone{position:absolute;z-index:6;left:14px;right:calc(var(--rail) + 16px);bottom:calc(78px + var(--sab));display:flex;flex-direction:column;gap:7px;pointer-events:none}
.cap-chip{align-self:flex-start;font-size:11px;font-weight:800;letter-spacing:1px;text-transform:uppercase;color:var(--accent-deep);background:var(--accent-soft);border:1px solid color-mix(in srgb,var(--accent) 40%,transparent);padding:4px 10px;border-radius:999px;backdrop-filter:blur(6px)}
.cap-title{font-size:19px;font-weight:900;letter-spacing:-.3px;color:var(--text)}
.cap-text{font-size:15.5px;line-height:1.5;font-weight:600;color:#3c5140;min-height:44px;max-height:calc(1.5em * 3.55);overflow-y:auto;pointer-events:auto;scrollbar-width:thin;-webkit-overflow-scrolling:touch}
.cap-text .w{opacity:.5;transition:opacity .15s,color .15s,text-shadow .15s}
.cap-text .w.on{opacity:1;color:#3c5140;text-shadow:none}
.cap-hint{font-size:12px;color:var(--muted);font-weight:700;display:flex;align-items:center;gap:6px;opacity:0;transition:opacity .4s}
.cap-hint.show{opacity:1}
.cap-hint .arr{display:inline-block;animation:hintUp 1.2s ease-in-out infinite}
@keyframes hintUp{0%,100%{transform:translateY(2px)}50%{transform:translateY(-3px)}}

/* ---------- action rail ---------- */
.rail{position:absolute;z-index:7;right:8px;bottom:calc(86px + var(--sab));display:flex;flex-direction:column;align-items:center;gap:16px}
.rail-btn{display:flex;flex-direction:column;align-items:center;gap:3px;color:#40514a}
.rail-btn .ic{width:48px;height:48px;border-radius:50%;display:grid;place-items:center;font-size:21px;background:rgba(255,255,255,.94);border:1px solid var(--line);box-shadow:0 4px 14px rgba(53,88,52,.14);transition:transform .15s,background .2s}
.rail-btn:active .ic{transform:scale(.88)}
.rail-btn .lb{font-size:10.5px;font-weight:800;opacity:.9}
.rail-btn.liked .ic{background:#fee2e2;border-color:rgba(248,113,113,.5)}
.rail-btn.liked .ic,.rail-btn.liked .lb{color:#e11d48}

/* ---------- tab bar ---------- */
#tabbar{
  position:absolute;z-index:40;inset-inline:0;bottom:0;display:flex;padding:8px 10px calc(10px + var(--sab));
  background:rgba(255,255,255,.9);backdrop-filter:blur(14px);border-top:1px solid var(--line);
}
.tab{flex:1;display:flex;flex-direction:column;align-items:center;gap:2px;padding:4px 0;color:var(--dim);font-weight:800;font-size:11.5px;letter-spacing:.2px;position:relative}
.tab .ti{font-size:20px;filter:grayscale(1) opacity(.55);transition:.2s}
.tab.active .ti{filter:none;transform:translateY(-1px) scale(1.08)}
.tab[data-section=python].active{color:var(--python-deep)}
.tab[data-section=genai].active{color:var(--genai-deep)}
.tab[data-section=agentic].active{color:var(--agentic-deep)}
.tp{width:56px;height:3px;border-radius:3px;background:rgba(53,88,52,.13);margin-top:2px;overflow:hidden}
.tp b{display:block;height:100%;width:0;background:currentColor;border-radius:3px;transition:width .5s}

/* ---------- hook ---------- */
.hook{position:absolute;inset:0;z-index:8;display:flex;align-items:center;justify-content:center;padding:30px;text-align:center;background:radial-gradient(100% 70% at 50% 40%,var(--accent-soft),transparent 70%)}
.hook-text{font-size:clamp(26px,7.5vw,40px);font-weight:900;line-height:1.18;letter-spacing:-.8px;opacity:0;transform:scale(.8);color:var(--text)}
.hook-text.pop{animation:hookPop .7s cubic-bezier(.2,1.4,.4,1) forwards}
.hook-text .hl{color:var(--accent-deep);text-shadow:0 2px 20px var(--accent-soft)}
@keyframes hookPop{0%{opacity:0;transform:scale(.7) translateY(24px)}100%{opacity:1;transform:scale(1) translateY(0)}}
.hook-skip{position:absolute;bottom:calc(96px + var(--sab));left:50%;transform:translateX(-50%);font-size:12px;color:var(--muted);font-weight:700;animation:blink 1.6s infinite}
@keyframes blink{50%{opacity:.35}}

/* ---------- big text / bridge / list / compare scenes ---------- */
.kicker{font-size:12px;font-weight:900;letter-spacing:2.5px;text-transform:uppercase;color:var(--accent-deep);margin-bottom:14px;opacity:0}
.big-h{font-size:clamp(26px,7vw,38px);font-weight:900;line-height:1.14;letter-spacing:-.7px;max-width:20ch;opacity:0;color:var(--text)}
.big-h .hl{color:var(--accent-deep);text-shadow:0 2px 20px var(--accent-soft)}
.big-sub{margin-top:16px;font-size:15px;color:var(--muted);font-weight:700;opacity:0}
.pop{animation:popIn .65s cubic-bezier(.2,1.3,.4,1) forwards}
.pop.d1{animation-delay:.12s}.pop.d2{animation-delay:.26s}.pop.d3{animation-delay:.4s}.pop.d4{animation-delay:.54s}
@keyframes popIn{0%{opacity:0;transform:translateY(26px) scale(.92)}100%{opacity:1;transform:none}}
.floaty{animation:floatY 3.4s ease-in-out infinite}
@keyframes floatY{0%,100%{transform:translateY(0)}50%{transform:translateY(-8px)}}

.list-card{display:flex;flex-direction:column;gap:12px;width:min(420px,86vw)}
.list-item{display:flex;align-items:center;gap:14px;text-align:left;background:rgba(255,255,255,.95);border:1px solid var(--line);border-left:3px solid var(--accent);border-radius:16px;padding:14px 16px;box-shadow:0 6px 20px -8px rgba(53,88,52,.18);opacity:0}
.list-item .dot{width:34px;height:34px;flex:none;border-radius:11px;display:grid;place-items:center;background:var(--accent-soft);font-size:17px}
.list-item b{font-size:15.5px;color:var(--text)}
.list-item{transition:border-color .3s,box-shadow .3s,transform .3s}
.list-item.hot{border-color:color-mix(in srgb,var(--accent) 65%,transparent);box-shadow:0 10px 28px -8px var(--accent-soft),0 0 0 4px var(--accent-soft);transform:scale(1.025)}
.list-item small{display:block;color:var(--muted);font-weight:600;font-size:12.5px;margin-top:2px}

.compare{display:flex;gap:12px;width:min(480px,92vw);align-items:stretch}
.vs{flex:none;align-self:center;font-weight:900;font-size:13px;color:var(--muted);background:#eef5ea;border:1px solid var(--line);width:38px;height:38px;border-radius:50%;display:grid;place-items:center}
.cmp-card{flex:1;background:rgba(255,255,255,.95);border:1px solid var(--line);border-radius:20px;padding:18px 14px;text-align:center;box-shadow:0 6px 20px -8px rgba(53,88,52,.18);opacity:0}
.cmp-card .em{font-size:34px}
.cmp-card h3{margin:8px 0 6px;font-size:16.5px;color:var(--text)}
.cmp-card p{font-size:13px;color:var(--muted);font-weight:600;line-height:1.5}
.cmp-card.win{border-color:color-mix(in srgb,var(--accent) 55%,transparent);box-shadow:0 12px 34px -10px var(--accent-soft)}

/* ---------- tokens scene ---------- */
.tokens-wrap{width:min(440px,92vw);display:flex;flex-direction:column;gap:22px;align-items:center}
.token-row{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;min-height:44px}
.tok{background:#ffffff;border:1px solid var(--line);border-radius:12px;padding:8px 13px;font-weight:800;font-size:16px;color:var(--text);opacity:0;box-shadow:0 4px 14px -4px rgba(53,88,52,.2)}
.tok.mask{border:2px dashed var(--accent-deep);color:var(--accent-deep);background:var(--accent-soft);animation:pulseG 1.1s ease-in-out infinite}
@keyframes pulseG{50%{box-shadow:0 0 0 6px var(--accent-soft)}}
.model-node{position:relative;width:118px;height:118px;border-radius:50%;display:grid;place-items:center;font-weight:900;font-size:14px;letter-spacing:.5px;
  background:radial-gradient(circle at 35% 30%,#ffffff,#f0f7ea 75%);
  border:2px solid color-mix(in srgb,var(--accent) 60%,#fff);box-shadow:0 14px 40px -10px var(--accent-soft),0 0 0 8px #ffffff80;color:var(--text)}
.model-node small{display:block;font-size:9.5px;font-weight:800;color:var(--accent-deep);letter-spacing:1.5px;margin-top:2px}
.model-node .orbit{position:absolute;inset:-14px;border-radius:50%;border:1.5px dashed color-mix(in srgb,var(--accent) 45%,transparent);animation:spin 9s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.prob-list{display:flex;flex-direction:column;gap:9px;width:min(320px,78vw)}
.prob{display:flex;align-items:center;gap:10px;font-weight:800;font-size:14px}
.prob .pw{width:64px;text-align:right;color:var(--text)}
.prob .bar{flex:1;height:12px;border-radius:8px;background:rgba(53,88,52,.12);overflow:hidden}
.prob .bar i{display:block;height:100%;width:0;border-radius:8px;background:linear-gradient(90deg,color-mix(in srgb,var(--accent) 55%,#9db892),var(--accent));transition:width .9s cubic-bezier(.2,.9,.3,1)}
.prob .pc{width:42px;color:var(--muted);font-size:12.5px}
.prob.win .pw{color:var(--accent-deep)}
.prob.win .bar i{background:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}
.flowline{display:flex;align-items:center;gap:10px;color:var(--muted);font-size:12px;font-weight:800;letter-spacing:1px;text-transform:uppercase;opacity:.85}

/* ---------- vector / embed scenes ---------- */
.vspace{width:min(440px,94vw);display:flex;flex-direction:column;gap:10px;align-items:center}
.vplane{position:relative;width:100%;aspect-ratio:1.35;background:#ffffff;border:1px solid var(--line);border-radius:20px;overflow:hidden;box-shadow:0 10px 30px -12px rgba(53,88,52,.2);
  background-image:radial-gradient(rgba(53,88,52,.09) 1px,transparent 1px);background-size:22px 22px}
.vdot{position:absolute;display:flex;flex-direction:column;align-items:center;transform:translate(-50%,-50%);opacity:0}
.vdot .p{width:13px;height:13px;border-radius:50%;background:var(--dc,#94a3b8);box-shadow:0 0 0 4px #ffffff,0 0 12px var(--dc,#94a3b8)}
.vdot .n{font-size:11.5px;font-weight:800;margin-top:5px;color:#33463a;text-shadow:0 1px 4px #fff,0 0 6px #fff;white-space:nowrap}
.vdot.hi .p{width:17px;height:17px}
.vline{position:absolute;height:3px;transform-origin:0 50%;border-radius:3px;opacity:0}
.vtag{position:absolute;transform:translate(-50%,-50%);font-size:11.5px;font-weight:900;padding:4px 10px;border-radius:999px;opacity:0;white-space:nowrap;backdrop-filter:blur(4px)}
.embed-wrap{width:min(460px,94vw);display:flex;flex-direction:column;gap:16px;align-items:center}
.embed-eq{display:flex;align-items:center;gap:12px;flex-wrap:wrap;justify-content:center}
.embed-word{font-size:26px;font-weight:900;padding:10px 20px;border-radius:16px;background:var(--accent-soft);border:1.5px solid color-mix(in srgb,var(--accent) 45%,transparent);color:var(--accent-deep)}
.embed-arrow{font-size:22px;color:var(--dim);animation:hintRight 1.3s ease-in-out infinite}
@keyframes hintRight{50%{transform:translateX(6px)}}
.embed-vec{display:flex;gap:5px;flex-wrap:wrap;justify-content:center;max-width:330px}
.dim-chip{min-width:30px;padding:6px 4px;border-radius:8px;background:#ffffff;border:1px solid var(--line);font-size:11px;font-weight:800;color:var(--text);font-variant-numeric:tabular-nums;opacity:0;box-shadow:0 2px 8px -2px rgba(53,88,52,.15)}
.dim-chip.gold{background:#fff8e1;border-color:#ffe082;color:#b45309}
.embed-dims{font-size:13px;font-weight:800;color:var(--muted);letter-spacing:.4px}
.embed-dims b{color:var(--accent-deep)}

/* ---------- agent loop scene ---------- */
.loop-wrap{position:relative;width:min(320px,80vw);aspect-ratio:1;margin-top:6px}
.loop-core{position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);width:96px;height:96px;border-radius:50%;display:grid;place-items:center;text-align:center;
  background:radial-gradient(circle at 35% 30%,#ffffff,#edf5e6 75%);
  border:2px solid color-mix(in srgb,var(--accent) 60%,#fff);box-shadow:0 12px 36px -10px var(--accent-soft),0 0 0 7px #ffffff80;color:var(--text);font-weight:900;font-size:13px;z-index:3}
.loop-core small{display:block;font-size:9px;color:var(--accent-deep);letter-spacing:1.2px;font-weight:800}
.loop-node{position:absolute;width:78px;height:78px;border-radius:22px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:1px;
  background:rgba(255,255,255,.96);border:1.5px solid var(--line);font-weight:900;font-size:11.5px;color:var(--text);box-shadow:0 6px 18px -6px rgba(53,88,52,.2);opacity:0;z-index:2}
.loop-node .e{font-size:20px}
.loop-node.hot{border-color:var(--accent);box-shadow:0 8px 26px -6px var(--accent-soft),0 0 0 4px var(--accent-soft);color:var(--accent-deep)}
.loop-ring{position:absolute;inset:6px;border-radius:50%;border:1.5px dashed color-mix(in srgb,var(--accent) 40%,transparent);animation:spin 12s linear infinite}
.loop-chip{position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);z-index:5;background:#ffffff;border:1.5px solid var(--accent);color:var(--accent-deep);font-size:11px;font-weight:900;padding:6px 11px;border-radius:999px;box-shadow:0 6px 18px -4px var(--accent-soft);opacity:0;white-space:nowrap}

/* ---------- diagram / chat scenes ---------- */
.diagram{display:flex;flex-direction:column;align-items:center;gap:0;width:min(430px,92vw)}
.dia-row{display:flex;align-items:center;gap:10px;width:100%}
.dia-node{flex:1;background:rgba(255,255,255,.96);border:1px solid var(--line);border-radius:16px;padding:12px 8px;text-align:center;font-weight:800;font-size:13px;color:var(--text);opacity:0;position:relative;box-shadow:0 6px 18px -8px rgba(53,88,52,.18)}
.dia-node .e{display:block;font-size:22px;margin-bottom:4px}
.dia-node small{display:block;font-size:10.5px;color:var(--muted);font-weight:700;margin-top:3px;line-height:1.35}
.dia-node.hot{border-color:var(--accent);box-shadow:0 8px 26px -8px var(--accent-soft),0 0 0 4px var(--accent-soft)}
.dia-link{width:26px;flex:none;display:flex;flex-direction:column;align-items:center;gap:2px;opacity:0}
.dia-link .stem{width:100%;height:2px;background:color-mix(in srgb,var(--accent) 55%,#fff);position:relative;overflow:hidden;border-radius:2px}
.dia-link .stem i{position:absolute;top:0;bottom:0;width:8px;background:var(--accent);border-radius:2px;animation:packet 1.15s linear infinite}
@keyframes packet{from{left:-10px}to{left:100%}}
.dia-link .lb{font-size:8.5px;font-weight:900;color:var(--dim);letter-spacing:.6px;text-transform:uppercase}
.chat-wrap{width:min(380px,88vw);display:flex;flex-direction:column;gap:10px}
.bubble{max-width:82%;padding:11px 15px;border-radius:18px;font-size:13.5px;font-weight:600;line-height:1.45;opacity:0;text-align:left;color:var(--text);box-shadow:0 4px 14px -6px rgba(53,88,52,.2)}
.bubble.you{align-self:flex-end;background:color-mix(in srgb,var(--accent) 16%,#fff);border:1px solid color-mix(in srgb,var(--accent) 40%,transparent);border-bottom-right-radius:6px}
.bubble.bot{align-self:flex-start;background:#ffffff;border:1px solid var(--line);border-bottom-left-radius:6px}
.bubble .tool{display:inline-block;margin-top:6px;font-size:11px;font-weight:900;color:var(--accent-deep);background:var(--accent-soft);border:1px solid color-mix(in srgb,var(--accent) 40%,transparent);padding:3px 9px;border-radius:999px}

/* ---------- recap ---------- */
.recap{position:absolute;inset:0;z-index:9;display:flex;flex-direction:column;justify-content:center;gap:12px;padding:26px;background:linear-gradient(rgba(244,250,242,.72),rgba(239,248,236,.92))}
.recap-h{font-size:13px;font-weight:900;letter-spacing:2px;text-transform:uppercase;color:var(--accent-deep);text-align:center;margin-bottom:6px}
.recap-card{display:flex;align-items:center;gap:13px;background:rgba(255,255,255,.97);border:1px solid color-mix(in srgb,var(--accent) 35%,var(--line));border-radius:18px;padding:15px 16px;font-weight:800;font-size:14.5px;text-align:left;color:var(--text);box-shadow:0 8px 24px -10px rgba(53,88,52,.2);opacity:0}
.recap-card .n{flex:none;width:30px;height:30px;border-radius:10px;display:grid;place-items:center;background:var(--accent);color:#fff;font-weight:900;font-size:14px}

/* ---------- quiz ---------- */
.quiz{position:absolute;inset:0;z-index:10;display:flex;align-items:flex-end;justify-content:center;padding:14px 16px calc(92px + var(--sab));background:rgba(28,43,30,.32);backdrop-filter:blur(5px)}
.quiz-card{width:min(430px,100%);max-height:100%;overflow-y:auto;background:var(--panel);border:1px solid var(--line);border-radius:24px;padding:18px 16px 16px;text-align:left;box-shadow:0 -8px 50px rgba(28,43,30,.25);scrollbar-width:thin}
.quiz-tag{display:inline-block;font-size:11px;font-weight:900;letter-spacing:1.5px;text-transform:uppercase;color:var(--accent-deep);background:var(--accent-soft);border:1px solid color-mix(in srgb,var(--accent) 40%,transparent);padding:4px 11px;border-radius:999px;margin-bottom:12px}
.quiz-q{font-size:17.5px;font-weight:900;line-height:1.35;margin-bottom:14px;color:var(--text)}
.quiz-opts{display:flex;flex-direction:column;gap:9px}
.quiz-opt{display:flex;align-items:center;gap:11px;background:#f6faf3;border:1.5px solid var(--line);border-radius:14px;padding:11px 13px;font-weight:700;font-size:13.5px;text-align:left;transition:.18s;color:var(--text);opacity:0;animation:popIn .4s forwards}
.quiz-opt .k{flex:none;width:26px;height:26px;border-radius:8px;display:grid;place-items:center;background:rgba(53,88,52,.09);font-size:12px;font-weight:900}
.quiz-opt:not(:disabled):active{border-color:var(--accent)}
.quiz-opt.right{background:#dcfce7;border-color:var(--ok);animation:rightPulse .5s}
.quiz-opt.right .k{background:var(--ok);color:#fff}
.quiz-opt.wrong{background:#fee2e2;border-color:var(--danger);animation:shakeX .45s}
.quiz-opt.wrong .k{background:var(--danger);color:#fff}
.quiz-opt.dim{opacity:.45}
@keyframes rightPulse{0%{transform:scale(1)}40%{transform:scale(1.03)}100%{transform:scale(1)}}
@keyframes shakeX{0%,100%{transform:translateX(0)}20%,60%{transform:translateX(-7px)}40%,80%{transform:translateX(7px)}}
.quiz-why{margin-top:13px;font-size:13px;font-weight:600;color:var(--muted);line-height:1.5;display:none}
.quiz-why.show{display:block;animation:popIn .4s}
.quiz-next{margin-top:14px;width:100%;padding:13px;border-radius:14px;font-weight:900;font-size:14.5px;background:var(--accent-deep);color:#fff;display:none;box-shadow:0 8px 22px -8px var(--accent-soft)}
.quiz-next.show{display:block;animation:popIn .35s}
.quiz-done{display:flex;align-items:center;justify-content:center;gap:9px;margin-top:14px;font-weight:900;color:var(--ok);font-size:14.5px}

/* ---------- teaser cards ---------- */
.teaser{height:100%;scroll-snap-align:start;scroll-snap-stop:always;position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:30px;text-align:center;
  --accent:var(--genai);--accent-deep:var(--genai-deep);--accent-soft:rgba(101,163,13,.13)}
.teaser[data-section=python]{--accent:var(--python);--accent-deep:var(--python-deep);--accent-soft:rgba(245,158,11,.14)}
.teaser[data-section=agentic]{--accent:var(--agentic);--accent-deep:var(--agentic-deep);--accent-soft:rgba(13,148,136,.12)}
.teaser-card{width:min(420px,90vw);background:rgba(255,255,255,.82);border:1.5px dashed color-mix(in srgb,var(--accent) 45%,var(--line));border-radius:26px;padding:30px 24px;box-shadow:0 12px 34px -14px rgba(53,88,52,.25)}
.teaser .soon{display:inline-block;font-size:11px;font-weight:900;letter-spacing:1.6px;text-transform:uppercase;color:var(--accent-deep);background:var(--accent-soft);padding:5px 12px;border-radius:999px;border:1px solid color-mix(in srgb,var(--accent) 35%,transparent)}
.teaser h3{font-size:22px;font-weight:900;margin:14px 0 8px;letter-spacing:-.4px;color:var(--text)}
.teaser p{color:var(--muted);font-size:13.5px;font-weight:600;line-height:1.55}
.teaser .mini-list{margin-top:16px;display:flex;flex-direction:column;gap:7px;text-align:left}
.teaser .mini-list div{font-size:12.5px;font-weight:700;color:#3c5140;display:flex;gap:9px;align-items:baseline}
.teaser .mini-list div::before{content:"▸";color:var(--accent-deep);flex:none}
.teaser .count{margin-top:16px;font-size:12px;font-weight:800;color:var(--dim);letter-spacing:.4px}

/* ---------- big play / pause ---------- */
.bigplay{position:absolute;z-index:9;left:50%;top:44%;transform:translate(-50%,-50%);width:88px;height:88px;border-radius:50%;display:none;place-items:center;font-size:30px;color:var(--accent-deep);
  background:rgba(255,255,255,.9);border:2px solid var(--accent);box-shadow:0 10px 40px -6px var(--accent-soft);animation:popIn .25s}
.bigplay.show{display:grid}
.speedpill{position:absolute;z-index:9;left:50%;top:26%;transform:translateX(-50%);display:none;font-size:12.5px;font-weight:900;letter-spacing:1px;background:rgba(255,255,255,.94);border:1.5px solid var(--accent);color:var(--accent-deep);padding:7px 15px;border-radius:999px;box-shadow:0 6px 18px -6px var(--accent-soft)}
.speedpill.show{display:block;animation:popIn .2s}

/* ---------- sheets ---------- */
#scrim{position:fixed;inset:0;z-index:60;background:rgba(20,32,22,.4);opacity:0;pointer-events:none;transition:opacity .3s}
#scrim.on{opacity:1;pointer-events:auto}
.sheet{position:fixed;z-index:70;background:var(--bg2);border:1px solid var(--line);display:flex;flex-direction:column;transition:transform .42s cubic-bezier(.32,.9,.3,1)}
.sheet.right{top:0;right:0;bottom:0;width:min(440px,94vw);border-radius:22px 0 0 22px;transform:translateX(105%);box-shadow:-20px 0 60px rgba(28,43,30,.25)}
.sheet.bottom{left:0;right:0;bottom:0;max-height:84dvh;border-radius:26px 26px 0 0;transform:translateY(106%);box-shadow:0 -20px 60px rgba(28,43,30,.25);padding-bottom:var(--sab)}
.sheet.open{transform:none}
.grab{width:44px;height:5px;border-radius:5px;background:rgba(53,88,52,.25);margin:10px auto 2px;flex:none}
.sheet-head{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:10px 16px 10px;flex:none;border-bottom:1px solid var(--line)}
.sheet-title{font-weight:900;font-size:15.5px;letter-spacing:-.2px;color:var(--text)}
.sheet-scroll{overflow-y:auto;padding:16px;flex:1;scrollbar-width:thin}

/* code */
.code{font-family:"SF Mono",ui-monospace,Menlo,Consolas,monospace;font-size:12.8px;line-height:1.75;background:#101826;border:1px solid rgba(255,255,255,.08);border-radius:16px;padding:16px;overflow-x:auto;white-space:pre;color:#dbe4f5;user-select:text;-webkit-user-select:text}
.code .c-k{color:#c792ea}.code .c-s{color:#c3e88d}.code .c-n{color:#f78c6c}.code .c-c{color:#546178;font-style:italic}.code .c-f{color:#82aaff}.code .c-d{color:#89ddff}.code .c-m{color:#ffcb6b}
.annotes{margin-top:14px;display:flex;flex-direction:column;gap:9px}
.annotes div{font-size:13px;font-weight:600;color:#3c5140;background:#f4f8f1;border-left:3px solid var(--genai);border-radius:0 12px 12px 0;padding:10px 12px;line-height:1.55}
.annotes div b{color:var(--genai-deep)}

/* notes */
.notes-body{font-size:14.5px;line-height:1.7;user-select:text;-webkit-user-select:text;color:#3c5140}
.notes-body h3{font-size:18px;font-weight:900;margin:6px 0 12px;letter-spacing:-.3px;color:var(--text)}
.notes-body h4{font-size:15px;font-weight:900;margin:18px 0 7px;color:var(--genai-deep)}
.notes-body p{margin:0 0 11px;font-weight:500}
.notes-body ul{margin:0 0 12px 4px;list-style:none;display:flex;flex-direction:column;gap:6px}
.notes-body ul li{padding-left:18px;position:relative;font-weight:500}
.notes-body ul li::before{content:"▸";position:absolute;left:0;color:var(--genai-deep)}
.notes-body code{font-family:"SF Mono",ui-monospace,Menlo,monospace;font-size:12px;background:#eef6e6;border:1px solid #d3e5bd;padding:1.5px 6px;border-radius:6px;color:#3f6212}
.notes-body .nb{background:#f1f8e9;border:1px solid #dcebc7;border-radius:14px;padding:12px 14px;margin:0 0 12px;font-weight:600;color:#33510f}
.notes-body b{color:#2f4a12;font-weight:800}
.notes-body i{color:#57705a}
.notes-body .ntb{width:100%;border-collapse:collapse;margin:0 0 14px;font-size:13px}
.notes-body .ntb th{text-align:left;color:var(--genai-deep);font-weight:900;padding:8px 10px;border-bottom:1.5px solid rgba(101,163,13,.4)}
.notes-body .ntb td{padding:8px 10px;border-bottom:1px solid var(--line);font-weight:500;vertical-align:top}
.notes-body .ntb tr:last-child td{border-bottom:0}

/* settings */
.set-body{display:flex;flex-direction:column;gap:14px}
.set-row{display:flex;align-items:center;justify-content:space-between;gap:12px;font-weight:800;font-size:14px;background:#f6faf3;border:1px solid var(--line);border-radius:14px;padding:13px 14px;flex-wrap:wrap;color:var(--text)}
.set-row select{background:#fff;color:var(--text);border:1px solid var(--line);border-radius:10px;padding:8px 10px;font-weight:700;max-width:58vw}
.set-row input[type=range]{flex-basis:100%;accent-color:var(--genai)}
.set-row input[type=checkbox]{width:22px;height:22px;accent-color:var(--genai)}
.set-row b{color:var(--genai-deep)}
.danger{padding:13px;border-radius:14px;font-weight:900;background:#fef2f2;border:1px solid #fca5a5;color:#dc2626}
.set-hint{text-align:center;font-size:12px;color:var(--dim);font-weight:600;line-height:1.6}

/* ---------- toast ---------- */
#toast{position:fixed;z-index:90;left:50%;bottom:calc(92px + var(--sab));transform:translateX(-50%) translateY(20px);background:#ffffff;border:1px solid var(--line);color:var(--text);padding:11px 18px;border-radius:999px;font-weight:800;font-size:13px;opacity:0;transition:.35s;pointer-events:none;box-shadow:0 10px 30px rgba(28,43,30,.2);white-space:nowrap;max-width:92vw}
#toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* ---------- fx ---------- */
.fx-heart{position:fixed;z-index:95;font-size:64px;pointer-events:none;transform:translate(-50%,-50%);text-shadow:0 0 26px #f43f5e}
.fx-p{position:fixed;z-index:95;pointer-events:none;border-radius:50%}
.done-pop{position:absolute;z-index:11;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;background:rgba(240,248,236,.55);backdrop-filter:blur(3px)}
.done-pop .ck{width:84px;height:84px;border-radius:50%;display:grid;place-items:center;font-size:38px;background:#dcfce7;border:2px solid var(--ok);box-shadow:0 10px 34px -8px rgba(22,163,74,.4);animation:popIn .5s cubic-bezier(.2,1.5,.4,1)}
.done-pop b{font-size:17px;font-weight:900;color:var(--text)}
.done-pop small{font-size:12.5px;color:var(--muted);font-weight:700}

/* ---------- arch + diffapprove scene components ---------- */
.arch-stack{display:flex;flex-direction:column;align-items:center;width:min(380px,88vw)}
.arch-layer{display:flex;align-items:center;gap:12px;width:100%;background:rgba(255,255,255,.96);border:1.5px solid var(--line);border-radius:16px;padding:12px 14px;text-align:left;box-shadow:0 6px 18px -8px rgba(53,88,52,.18);opacity:0}
.arch-layer .e{font-size:24px;flex:none}
.arch-layer b{font-size:14.5px;color:var(--text);display:block}
.arch-layer small{font-size:11.5px;color:var(--muted);font-weight:600}
.arch-layer.hot{border-color:var(--accent);box-shadow:0 8px 26px -8px var(--accent-soft),0 0 0 4px var(--accent-soft)}
.arch-link-v{width:2.5px;height:26px;position:relative;overflow:hidden;background:color-mix(in srgb,var(--accent) 40%,#fff);border-radius:2px;opacity:0}
.arch-link-v .stem{position:absolute;inset:0}
.arch-link-v i{position:absolute;left:0;right:0;height:8px;background:var(--accent);border-radius:2px;animation:vpacket 1.1s linear infinite;box-shadow:0 0 8px var(--accent)}
@keyframes vpacket{from{top:-10px}to{top:100%}}
.diff-wrap{width:min(430px,92vw);background:#fff;border:1px solid var(--line);border-radius:18px;box-shadow:0 10px 30px -12px rgba(53,88,52,.22);overflow:hidden;text-align:left}
.diff-head{display:flex;align-items:center;justify-content:space-between;padding:11px 14px;border-bottom:1px solid var(--line);background:#f6faf3;font-weight:800;font-size:13px;color:var(--text)}
.diff-head .pill{font-size:11px;padding:4px 10px;border-radius:999px;font-weight:900}
.diff-head .pill.wait{background:#fff8e1;border:1px solid #ffe082;color:#b45309}
.diff-head .pill.ok{background:#dcfce7;border:1px solid #86efac;color:#15803d}
.diff-table{padding:6px 8px 10px}
.diff-row{display:grid;grid-template-columns:44px 1fr 18px 1fr 84px;gap:6px;align-items:center;padding:8px 6px;border-bottom:1px dashed var(--line);font-size:12.5px;font-weight:700;color:var(--text);opacity:0}
.diff-row.hd{opacity:1;font-size:10px;text-transform:uppercase;letter-spacing:.6px;color:var(--dim);border-bottom:1.5px solid var(--line)}
.diff-row:last-child{border-bottom:0}
.diff-row .cell{font-family:ui-monospace,Menlo,monospace;color:var(--accent-deep);font-weight:900}
.diff-row .before{color:var(--dim);text-decoration:line-through;text-decoration-color:rgba(220,38,38,.5)}
.diff-row .arr{color:var(--dim);text-align:center}
.diff-row .after{background:#dcfce7;border-radius:8px;padding:4px 8px;color:#15803d}
.diff-row .rule{font-size:10.5px;color:var(--muted);font-weight:600}

@media (min-width:700px){
  #app{max-width:520px;margin:0 auto;background:linear-gradient(#ffffff,#f2f9ee);border-inline:1px solid var(--line);box-shadow:0 0 60px rgba(53,88,52,.16)}
  body{background:radial-gradient(80% 60% at 50% 0%,#d7ecd2,var(--bg))}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
}

/* ============ LKG — course mode additions ============ */
.top-right{display:flex;align-items:center;gap:10px}
.brand-sub{margin-left:8px;font-size:10px;font-weight:800;letter-spacing:1.6px;text-transform:uppercase;color:var(--muted);align-self:center}
.prog-pill{font-size:12px;font-weight:900;color:var(--genai-deep);background:var(--accent-soft);border:1px solid color-mix(in srgb,var(--accent) 40%,transparent);padding:5px 11px;border-radius:999px;white-space:nowrap}

/* stage dividers inside the feed */
.stage-divider{min-height:100%;display:flex;align-items:center;justify-content:center;padding:30px;scroll-snap-align:start;background:linear-gradient(160deg,#f0f7ea,#e5f2dd)}
.sd-card{text-align:center;background:rgba(255,255,255,.92);border:1px solid var(--line);border-radius:26px;padding:36px 30px;box-shadow:0 18px 50px -18px rgba(53,88,52,.28);max-width:420px}
.sd-kicker{font-size:11px;font-weight:900;letter-spacing:3px;color:var(--accent-deep)}
.sd-card h2{margin:10px 0 8px;font-size:26px;letter-spacing:-.5px;color:var(--text)}
.sd-meta{font-size:13px;font-weight:700;color:var(--muted)}

/* chapter chip + chapter dot bar */
.chap-chip{font-size:10.5px;font-weight:900;letter-spacing:1.2px;text-transform:uppercase;color:var(--muted);min-height:14px}
.chapbar{display:flex;gap:7px;pointer-events:auto;margin-bottom:2px}
.chap-dot{position:relative;width:26px;height:26px;border-radius:50%;border:1.5px solid color-mix(in srgb,var(--accent) 45%,#fff);background:rgba(255,255,255,.85);display:grid;place-items:center;cursor:pointer;padding:0}
.chap-dot span{font-size:11px;font-weight:900;color:var(--muted)}
.chap-dot i{position:absolute;inset:2px;border-radius:50%;background:var(--accent-soft);opacity:0;transform:scale(.4);transition:.25s}
.chap-dot.on{border-color:var(--accent-deep)}
.chap-dot.on span{color:var(--accent-deep)}
.chap-dot.on i{opacity:1;transform:scale(1)}

/* quiz next button already styled by base; welcome + teaser reuse base styles */
@media (prefers-reduced-motion:reduce){
  .loop-ring,.model-node .orbit{animation:none}
}

/* ---------- motion upgrade (canvas bg + lottie) ---------- */
.bg-fx{position:absolute;inset:0;width:100%;height:100%;opacity:.7;pointer-events:none}
.hook-lottie{position:absolute;top:10%;left:50%;transform:translateX(-50%);width:116px;height:116px;pointer-events:none;opacity:.95}
.hook-lottie svg{width:100%!important;height:100%!important}

/* ---------- about sheet ---------- */
.about-body{font-size:14.5px;line-height:1.7;color:#3c5140;text-align:center;user-select:text;-webkit-user-select:text}
.about-hero{display:flex;flex-direction:column;align-items:center;gap:10px;margin-bottom:18px}
.about-logo{width:128px;height:128px;border-radius:32px;box-shadow:0 12px 34px -10px rgba(13,148,136,.35);background:radial-gradient(circle at 35% 30%,#ffffff,#e6f4ea 75%)}
.about-madeby{font-size:15px;font-weight:800;color:var(--muted);letter-spacing:.4px}
.about-madeby b{font-size:17px;font-weight:900;background:linear-gradient(90deg,#0d9488,#65a30d);-webkit-background-clip:text;background-clip:text;color:transparent;letter-spacing:1px}
.about-body p{margin:0 0 12px;font-weight:500}
.about-body b{color:#2f4a12;font-weight:800}
.about-facts{display:flex;flex-direction:column;gap:9px;margin:16px 0;text-align:left}
.about-fact{background:#f6faf3;border:1px solid var(--line);border-left:3px solid var(--genai);border-radius:0 14px 14px 0;padding:11px 13px;font-weight:600;font-size:13.5px;line-height:1.55}
.about-sign{margin-top:16px;font-size:15px}
.about-sign small{color:var(--dim);font-weight:700}
.about-hint{font-size:13px;color:var(--muted);font-weight:600;margin-top:8px}
.about-hint a{color:var(--genai-deep);font-weight:900;text-decoration:none}
.set-btn{width:100%;text-align:left;cursor:pointer}