*{box-sizing:border-box}
html,body{margin:0;background:#fbf6ee;color:#1e0b0a;font:15px/1.55 'Manrope','Segoe UI',Roboto,'Noto Sans','Noto Sans Bengali',Arial,sans-serif;-webkit-font-smoothing:antialiased}
.auth{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:40px 20px}
.auth-brand{display:flex;flex-direction:column;align-items:center;gap:10px;text-decoration:none;margin-bottom:24px}
.auth-brand .brand-badge{width:88px;height:88px;border-radius:50%;background:#fff;box-shadow:0 10px 26px -12px rgba(91,6,9,.5)}
.wordmark{display:inline-flex;align-items:baseline;gap:2px}
.wordmark .w-as{font:800 28px/1.15 'Noto Serif Bengali','Noto Sans Bengali',serif;background:linear-gradient(180deg,#d4141b 0%,#b70e14 45%,#3b0508 100%);-webkit-background-clip:text;background-clip:text;color:transparent}
.wordmark .w-tld{font:800 16px/1 'Manrope',Arial,sans-serif;color:#b70e14}
.auth-card{width:100%;max-width:410px;background:#fffdf8;border:1px solid #eadcc4;border-radius:18px;padding:28px;box-shadow:0 24px 60px -30px rgba(70,20,10,.3)}
.auth-tabs{display:grid;grid-template-columns:1fr 1fr;background:#f3ecdc;border-radius:11px;padding:4px;margin-bottom:22px}
.auth-tabs button{border:0;background:none;padding:9px;border-radius:8px;font:inherit;font-weight:700;color:#8a7464;cursor:pointer}
.auth-tabs button.on{background:#fff;color:#5a0609;box-shadow:0 1px 3px rgba(70,20,10,.12)}
h1{font:700 23px/1.2 'Fraunces',Georgia,serif;color:#5a0609;margin:0 0 6px}
.auth-sub{margin:0 0 20px;color:#8a7464}
.field{margin-bottom:15px}
label{display:block;font-size:13px;font-weight:700;margin-bottom:6px;color:#4a2e26}
input{width:100%;padding:11px 12px;border:1px solid #eadcc4;border-radius:10px;font:inherit;color:#1e0b0a;background:#fff}
input:focus{outline:none;border-color:#b70e14;box-shadow:0 0 0 3px rgba(183,14,20,.12)}
.pw{position:relative}.pw input{padding-right:64px}
.pw button{position:absolute;right:6px;top:50%;transform:translateY(-50%);border:0;background:none;font:inherit;font-size:13px;color:#8a7464;padding:6px 8px;cursor:pointer}
.hint{font-size:12.5px;color:#8a7464;margin:6px 0 0}
.error{background:#fbe4df;color:#7d251d;border-radius:9px;padding:10px 12px;font-size:14px;margin:0 0 14px}
.primary{width:100%;padding:12px;border:0;border-radius:11px;background:linear-gradient(180deg,#c8121a,#b70e14 55%,#8a0a0f);color:#fff;font:inherit;font-weight:700;cursor:pointer;box-shadow:0 10px 22px -12px rgba(183,14,20,.7)}
.primary:hover{background:linear-gradient(180deg,#b70e14,#5a0609)}.primary:disabled{opacity:.65;cursor:wait}
.auth-foot{text-align:center;margin:18px 0 0;color:#8a7464;font-size:14px}
.link{border:0;background:none;color:#b70e14;font:inherit;font-weight:700;text-decoration:underline;cursor:pointer;padding:0}
.auth-note{max-width:410px;text-align:center;color:#8a7464;font-size:12.5px;margin-top:20px}
button:focus-visible,a:focus-visible{outline:3px solid #f1b94c;outline-offset:2px}
[hidden]{display:none!important}
/* v7 readability */
html,body{background:#f6f6f7;color:#14100e;font-family:'Inter','Segoe UI',Roboto,Arial,sans-serif;font-size:16px}
.auth-card{background:#fff;border-color:#e4dfda}
h1{font-family:'Fraunces',Georgia,serif;font-weight:800;color:#14100e}
.auth-sub,.hint,.auth-foot,.auth-note{color:#5a504a}
label{color:#2e2622}
input{border-color:#d9d3cd;font-size:16px}
.auth-tabs{background:#efebe7}
.auth-top{display:flex;flex-direction:column;align-items:center;gap:12px;margin-bottom:22px}
.auth-top .auth-brand{margin-bottom:0}
.lang-switch{display:inline-flex;gap:2px;border:1.5px solid #e4dfda;border-radius:999px;padding:3px;background:#fff}
.lang-switch a{padding:6px 11px;border-radius:999px;font-size:13.5px;font-weight:800;text-decoration:none;color:#2e2622;line-height:1}
.lang-switch a.on{background:#14100e;color:#fff}
.lang-switch a[lang=as]{font-family:'Noto Sans Bengali',sans-serif}
html[lang=as] body{font-family:'Noto Sans Bengali','Inter',sans-serif;font-size:16.5px;line-height:1.7}
html[lang=as] h1{font-family:'Noto Serif Bengali',serif}
/* readable inactive tab and Show button */
.auth-tabs button{color:#4a3f3a}
.pw button{color:#4a3f3a;font-weight:600}

/* ============ v9.4: winning sunrise login ============ */
html,body{background:#fff8f0}
.auth-split{display:grid;min-height:100vh;padding:0;grid-template-columns:minmax(0,1.08fr) minmax(440px,1fr);grid-template-areas:"art panel";align-items:start;justify-content:stretch}
.auth-art{grid-area:art;position:sticky;top:0;height:100vh;margin:0;overflow:hidden;background:#2c2a3e}
.auth-art img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;object-position:50% 55%;display:block}
.auth-art::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(60,8,10,.26) 0%,rgba(60,8,10,0) 34%);pointer-events:none}
.auth-copy{grid-area:art;position:sticky;top:0;align-self:start;justify-self:start;z-index:2;margin:clamp(20px,3vw,40px);max-width:500px;padding:20px 24px;border-radius:18px;color:#fff;
  background:linear-gradient(180deg,rgba(52,7,10,.84),rgba(52,7,10,.72));-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);border:1px solid rgba(255,214,150,.32);box-shadow:0 24px 60px -28px rgba(40,4,6,.7)}
.copy-kicker{margin:0 0 6px;font-size:13px;font-weight:800;letter-spacing:.06em;text-transform:uppercase;color:#ffd58a}
.auth-copy h2{margin:0;font:800 clamp(23px,2.2vw,30px)/1.18 'Fraunces',Georgia,serif;color:#fff}
.copy-offer{display:flex;gap:10px;align-items:flex-start;margin:14px 0 0;padding:10px 14px;border-radius:12px;background:rgba(241,185,76,.18);border:1px solid rgba(241,185,76,.5);color:#fff;font-weight:700;font-size:15px;line-height:1.4}
.copy-offer::before{content:"\2605";flex:none;width:22px;height:22px;border-radius:50%;background:#ffd27a;color:#4a0507;text-align:center;line-height:22px;font-size:13px}
.auth-panel{grid-area:panel;min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:28px 24px;background:radial-gradient(120% 70% at 50% 0%,#fff3e2 0%,#fffaf4 55%,#ffffff 100%)}
.auth-top{margin-bottom:16px}
.auth-brand .brand-badge{width:72px;height:72px}
.auth-card{box-shadow:0 30px 70px -34px rgba(120,40,10,.38);border-color:#efe2d2}
.auth-assure{margin:10px 0 0;text-align:center;font-size:13.5px;color:#2f5a22;font-weight:600}
.auth-assure::before{content:"\2713  ";color:#2f7a3a;font-weight:900}
.auth-trust{width:100%;max-width:410px;margin-top:14px;padding:14px 18px;border-radius:14px;background:#fff;border:1px solid #efe2d2}
.auth-trust h2{margin:0 0 8px;font:800 14px/1.3 'Inter','Noto Sans Bengali',sans-serif;color:#5a0609}
.auth-trust ul{list-style:none;margin:0;padding:0;display:grid;gap:6px}
.auth-trust li{position:relative;padding-left:26px;font-size:14px;line-height:1.45;color:#2e2622}
.auth-trust li::before{content:"\2713";position:absolute;left:0;top:1px;width:18px;height:18px;border-radius:50%;background:#e4f2e6;color:#24672f;font-size:11px;font-weight:900;line-height:18px;text-align:center}
.auth-note{margin-top:14px}
@media (min-width:900px) and (max-height:800px){.copy-kicker{display:none}.auth-copy{padding:16px 20px}.auth-copy h2{font-size:22px}}
@media (max-width:899px){
  .auth-split{grid-template-columns:1fr;grid-template-areas:"art" "copy" "panel"}
  .auth-art{position:relative;height:auto;aspect-ratio:16/7}
  .auth-art img{object-position:center}
  .auth-art::after{display:none}
  .auth-copy{grid-area:copy;position:static;margin:0;max-width:none;justify-self:stretch;border-radius:0;border:0;padding:16px 18px;box-shadow:none;-webkit-backdrop-filter:none;backdrop-filter:none;background:linear-gradient(180deg,#5a0609,#3d0507)}
  .auth-copy h2{font-size:20px}
  .copy-offer{font-size:14px}
  .auth-panel{min-height:0;padding:20px 16px 28px;background:#fffaf4}
  .auth-brand .brand-badge{width:60px;height:60px}
}
html[lang=as] .auth-copy h2{font-family:'Noto Serif Bengali',serif;line-height:1.35}
html[lang=as] .copy-kicker{letter-spacing:0;text-transform:none}

.link{min-height:28px;padding:4px 2px;display:inline-flex;align-items:center}

/* v16.2: CC0 river photo (Syed Nuhel, WordPress Photo Directory) */
.auth-credit{position:absolute;right:12px;bottom:10px;z-index:1;margin:0;padding:4px 10px;border-radius:999px;background:rgba(20,16,24,.55);color:#f3eee9;font:500 12px/1.3 'Inter','Noto Sans Bengali',sans-serif;letter-spacing:0}
@media (max-width:899px){.auth-art img{object-position:50% 50%}.auth-credit{right:8px;bottom:6px;font-size:11px}}

/* ============ v16.3: depth, icon map, micro-interactions ============ */
.ic{display:block;flex:none;width:20px;height:20px}
.ic-lg{width:26px;height:26px}
/* Layered depth on the photo: image plane, warm light plane, glass cards */
.auth-split{--px:0;--py:0}
.auth-art picture{position:absolute;inset:0;display:block;animation:jjSettle 1.8s cubic-bezier(.2,.7,.2,1) both}
.auth-art img{transform:scale(1.06) translate3d(calc(var(--px)*-14px),calc(var(--py)*-10px),0);transition:transform .9s cubic-bezier(.2,.7,.2,1);will-change:transform}
.art-light{position:absolute;inset:-20%;z-index:0;pointer-events:none;mix-blend-mode:screen;opacity:.85;
  background:radial-gradient(32% 26% at 50% 44%,rgba(255,176,104,.34),rgba(255,176,104,0) 70%),radial-gradient(60% 40% at 50% 110%,rgba(40,12,60,.55),rgba(40,12,60,0) 70%);
  transform:translate3d(calc(var(--px)*6%),calc(var(--py)*5%),0);transition:transform 1.1s cubic-bezier(.2,.7,.2,1)}
.auth-copy{transform:perspective(1000px) rotateY(calc(var(--px)*3deg)) rotateX(calc(var(--py)*-2.5deg)) translate3d(calc(var(--px)*8px),calc(var(--py)*6px),0);transition:transform .8s cubic-bezier(.2,.7,.2,1);animation:jjRise .8s .15s cubic-bezier(.2,.7,.2,1) both}
.copy-stats{list-style:none;margin:14px 0 0;padding:0;display:flex;flex-wrap:wrap;gap:8px}
.copy-stats li{display:inline-flex;align-items:center;gap:8px;padding:6px 12px 6px 9px;border-radius:999px;background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.24);font-weight:700;font-size:13.5px;line-height:1.3;color:#fff}
.copy-stats .ic{width:18px;height:18px;color:#ffd58a}

/* Icon map: VEDA journey as a glass dock with extruded 3D tiles */
.auth-map{grid-area:art;position:sticky;bottom:0;align-self:end;justify-self:stretch;z-index:2;margin:0 clamp(20px,3vw,40px) 46px;padding:16px 18px 18px;border-radius:20px;color:#fff;
  background:linear-gradient(180deg,rgba(30,18,40,.8),rgba(24,12,32,.86));-webkit-backdrop-filter:blur(10px) saturate(1.2);backdrop-filter:blur(10px) saturate(1.2);border:1px solid rgba(255,214,150,.28);box-shadow:0 30px 60px -30px rgba(10,2,16,.85),inset 0 1px 0 rgba(255,255,255,.08);
  transform:perspective(1000px) rotateY(calc(var(--px)*2deg)) rotateX(calc(var(--py)*-2deg)) translate3d(calc(var(--px)*5px),calc(var(--py)*4px),0);transition:transform .8s cubic-bezier(.2,.7,.2,1);animation:jjRise .8s .3s cubic-bezier(.2,.7,.2,1) both}
.map-title{margin:0 0 10px;font:800 12.5px/1.3 'Inter','Noto Sans Bengali',sans-serif;letter-spacing:.08em;text-transform:uppercase;color:#ffd58a}
.map-path{position:absolute;left:4%;right:4%;top:40px;width:92%;height:60px;overflow:visible;pointer-events:none}
.map-path path{fill:none;stroke:rgba(255,213,138,.7);stroke-width:2;stroke-linecap:round;vector-effect:non-scaling-stroke;stroke-dasharray:1;stroke-dashoffset:1;animation:jjDraw 1.6s .6s cubic-bezier(.6,.1,.2,1) forwards}
.map-steps{position:relative;list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px;text-align:center}
.map-step{display:flex;flex-direction:column;align-items:center;gap:3px;animation:jjTile .7s calc(var(--i)*130ms + .55s) cubic-bezier(.2,.8,.2,1.15) both}
.map-ico{position:relative;display:grid;place-items:center;width:56px;height:56px;margin-bottom:6px;border-radius:17px;color:#8a0a0f;
  background:linear-gradient(160deg,#fffaf2 0%,#ffe6c4 58%,#f5c98f 100%);
  box-shadow:inset 0 1px 0 rgba(255,255,255,.95),inset 0 -3px 6px rgba(160,80,20,.18),0 3px 0 #c58a52,0 14px 22px -10px rgba(0,0,0,.7);
  transition:transform .35s cubic-bezier(.2,.8,.2,1.2),box-shadow .35s}
.map-step:nth-child(even) .map-ico{transform:translateY(-6px)}
.map-n{position:absolute;top:-7px;right:-7px;width:22px;height:22px;border-radius:50%;background:#b70e14;color:#fff;font:800 12px/22px 'Inter',sans-serif;box-shadow:0 0 0 2px #1e1228}
.map-step strong{font-size:15px;line-height:1.25;color:#fff}
.map-sub{font-size:12.5px;line-height:1.35;color:#efe4da}
@media (hover:hover) and (pointer:fine){.map-step:hover .map-ico{transform:translateY(-9px) rotateX(12deg);box-shadow:inset 0 1px 0 rgba(255,255,255,.95),inset 0 -3px 6px rgba(160,80,20,.18),0 5px 0 #c58a52,0 22px 26px -12px rgba(0,0,0,.75)}}
.auth-credit{bottom:12px}

/* Panel: staged reveal, sliding tab pill */
.auth-top{animation:jjRise .7s .05s cubic-bezier(.2,.7,.2,1) both}
.auth-card{animation:jjRise .7s .15s cubic-bezier(.2,.7,.2,1) both}
.auth-trust{animation:jjRise .7s .3s cubic-bezier(.2,.7,.2,1) both}
h1{font-family:'Inter','Noto Sans Bengali',sans-serif;font-weight:800;letter-spacing:-.02em}
.auth-tabs{position:relative;isolation:isolate}
.auth-tabs::before{content:"";position:absolute;z-index:-1;top:4px;bottom:4px;left:4px;width:calc(50% - 4px);border-radius:8px;background:#fff;box-shadow:0 1px 3px rgba(70,20,10,.14),0 6px 14px -8px rgba(70,20,10,.35);transition:transform .38s cubic-bezier(.2,.8,.2,1)}
.auth-tabs[data-mode=signup]::before{transform:translateX(100%)}
.auth-tabs button{position:relative;min-height:40px;transition:color .25s}
.auth-tabs button.on{background:transparent;box-shadow:none;color:#5a0609}

/* Fields with leading icons */
.ctl{position:relative}
.ctl .ic-field{position:absolute;left:12px;top:50%;transform:translateY(-50%);width:19px;height:19px;color:#7a6f68;pointer-events:none;transition:color .2s}
.ctl input{padding-left:40px;min-height:46px;transition:border-color .2s,box-shadow .2s}
.ctl:focus-within .ic-field{color:#b70e14}
.ctl.pw input{padding-right:52px}
.pw .pw-eye{right:3px;width:44px;height:44px;padding:0;display:grid;place-items:center;border-radius:10px;color:#4a3f3a}
.pw .pw-eye:hover{background:#f4efea}
.pw-eye .ic-eyeoff,.pw-eye.on .ic-eye{display:none}
.pw-eye.on .ic-eyeoff{display:block}
.caps{display:inline-flex;margin:8px 0 0;padding:5px 10px;border-radius:8px;background:#fff4dc;color:#6b4100;font-size:13px;font-weight:700}
.meter{display:flex;align-items:center;gap:10px;margin-top:9px;font-size:13px;color:#5a504a}
.meter-bar{flex:1;height:6px;border-radius:99px;background:#ece6e0;overflow:hidden}
.meter-bar i{display:block;height:100%;width:0;border-radius:inherit;background:#c0392b;transition:width .35s cubic-bezier(.2,.8,.2,1),background-color .35s}
.meter-bar i[data-lv="1"]{background:#d98a00}.meter-bar i[data-lv="2"]{background:#5b9a2f}.meter-bar i[data-lv="3"]{background:#1f7a3a}
.meter-txt b{color:#2e2622}

/* Primary button: arrow nudge, press depth, spinner */
.primary{display:flex;align-items:center;justify-content:center;gap:8px;min-height:48px;transition:transform .15s,box-shadow .25s}
.primary .ic-arrow{width:18px;height:18px;transition:transform .25s cubic-bezier(.2,.8,.2,1)}
.primary:hover .ic-arrow{transform:translateX(4px)}
.primary:active{transform:translateY(1px) scale(.99)}
.primary .spin{display:none;width:16px;height:16px;border-radius:50%;border:2px solid rgba(255,255,255,.4);border-top-color:#fff;animation:jjSpin .8s linear infinite}
.primary.busy .spin{display:inline-block}.primary.busy .ic-arrow{display:none}

/* Trust list with icon chips */
.auth-trust li{display:flex;gap:10px;align-items:flex-start;padding-left:0}
.auth-trust li::before{content:none;display:none}
.auth-trust li .ic{width:30px;height:30px;padding:6px;border-radius:9px;background:#fdf0e3;color:#8a0a0f}
.auth-trust li span{padding-top:4px}

@keyframes jjRise{from{opacity:0;translate:0 16px}to{opacity:1;translate:0 0}}
@keyframes jjTile{from{opacity:0;translate:0 18px;scale:.9}to{opacity:1;translate:0 0;scale:1}}
@keyframes jjSettle{from{scale:1.08}to{scale:1}}
@keyframes jjDraw{to{stroke-dashoffset:0}}
@keyframes jjSpin{to{rotate:360deg}}

@media (min-width:900px) and (max-height:760px){.map-sub{display:none}.auth-map{padding:12px 16px 14px;margin-bottom:42px}.map-ico{width:48px;height:48px;border-radius:15px}.map-path{top:34px}}
@media (max-width:899px){
  .auth-split{grid-template-areas:"art" "copy" "map" "panel"}
  .auth-art img{transform:none}
  .auth-copy,.auth-map{transform:none}
  .auth-map{grid-area:map;position:static;margin:0;border-radius:0;border:0;box-shadow:none;-webkit-backdrop-filter:none;backdrop-filter:none;background:#3d0507;padding:6px 14px 18px}
  .map-title{font-size:12px}
  .map-path{top:30px;height:44px}
  .map-ico{width:48px;height:48px;border-radius:15px}
  .map-n{box-shadow:0 0 0 2px #3d0507}
  .map-step strong{font-size:14px}
}
@media (max-width:599px){.map-sub{display:none}.map-steps{gap:6px}.copy-stats li{font-size:13px}}
@media (prefers-reduced-motion:reduce){
  .auth-art picture,.auth-copy,.auth-map,.map-step,.auth-top,.auth-card,.auth-trust{animation:none}
  .map-path path{animation:none;stroke-dashoffset:0}
  .auth-art img,.art-light,.auth-copy,.auth-map{transform:none;transition:none}
  .auth-art img{transform:scale(1.02)}
  .auth-tabs::before,.meter-bar i,.primary,.primary .ic-arrow,.map-ico{transition:none}
  .primary .spin{animation-duration:2.4s}
}
@media (forced-colors:active){.map-ico,.auth-tabs::before,.copy-stats li{border:1px solid CanvasText}.meter-bar{border:1px solid CanvasText}.meter-bar i{background:Highlight}}
html[lang=as] .map-title{letter-spacing:0;text-transform:none;font-size:13.5px}
html[lang=as] .map-step strong{font-size:14.5px}
html[lang=as] h1{font-family:'Noto Serif Bengali',serif;letter-spacing:0}
/* keep the photo credit visible beneath the map dock (sticky ignores margin) */
@media (min-width:900px){.auth-map{bottom:44px;margin-bottom:44px}}

/* ============ v16.4: kinetic headline + VEDA map that lights up with the form ============ */
.vh{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.kw-line{display:inline}
.kw{display:inline-block;opacity:0;translate:0 .55em;filter:blur(4px);animation:jjWord .6s calc(var(--d,0ms) + var(--w)*70ms) cubic-bezier(.2,.75,.2,1) forwards}
@keyframes jjWord{to{opacity:1;translate:0 0;filter:blur(0)}}
.map-path path.lit{animation:none;stroke:#ffd27a;stroke-width:3.2;stroke-dasharray:1;stroke-dashoffset:1;filter:drop-shadow(0 0 6px rgba(255,190,90,.75));transition:stroke-dashoffset .7s cubic-bezier(.3,.7,.2,1)}
.map-step .map-ico{transition:transform .35s cubic-bezier(.2,.8,.2,1.2),box-shadow .45s,background .45s,color .45s}
.map-step.lit .map-ico{color:#fff;background:linear-gradient(160deg,#e3242b 0%,#b70e14 55%,#7d070b 100%);
  box-shadow:inset 0 1px 0 rgba(255,255,255,.35),inset 0 -3px 6px rgba(0,0,0,.25),0 3px 0 #5a0609,0 0 0 3px rgba(255,210,122,.55),0 16px 26px -10px rgba(255,120,60,.6)}
.map-step.lit .map-n{background:#ffd27a;color:#4a0507}
.map-step.lit strong{color:#ffd58a}
.map-step.next .map-ico{animation:jjPulse 2.2s ease-in-out infinite}
@keyframes jjPulse{0%,100%{box-shadow:inset 0 1px 0 rgba(255,255,255,.95),inset 0 -3px 6px rgba(160,80,20,.18),0 3px 0 #c58a52,0 14px 22px -10px rgba(0,0,0,.7),0 0 0 0 rgba(255,210,122,.6)}
  50%{box-shadow:inset 0 1px 0 rgba(255,255,255,.95),inset 0 -3px 6px rgba(160,80,20,.18),0 3px 0 #c58a52,0 14px 22px -10px rgba(0,0,0,.7),0 0 0 7px rgba(255,210,122,0)}}
@media (prefers-reduced-motion:reduce){.kw{animation:none;opacity:1;translate:none;filter:none}.map-path path.lit{transition:none}.map-step.next .map-ico{animation:none}.map-step .map-ico{transition:none}}
@media (forced-colors:active){.map-step.lit .map-ico{background:Highlight;color:HighlightText}}
/* ============ v16.8 Login Phase 3: WebGL river layer over the CC0 photo ============ */
/* The photo stays underneath as the fallback; the canvas fades in only after its first frame is drawn. */
.art-river{position:absolute;inset:0;width:100%;height:100%;display:block;z-index:0;opacity:0;transition:opacity .9s ease;pointer-events:none}
.art-river.on{opacity:1}
.river-on .auth-art img{transform:scale(1.06)}
.river-toggle{position:absolute;left:12px;bottom:10px;z-index:3;display:inline-flex;align-items:center;gap:6px;min-height:28px;padding:4px 11px 4px 9px;border-radius:999px;border:1px solid rgba(255,255,255,.28);
  background:rgba(20,16,24,.6);color:#f3eee9;font:600 12px/1.3 'Inter','Noto Sans Bengali',sans-serif;cursor:pointer}
.river-toggle:hover{background:rgba(20,16,24,.78)}
.river-toggle:focus-visible{outline:3px solid #ffd58a;outline-offset:2px}
.auth-art.river-on .auth-credit{bottom:10px}
@media (min-width:900px){.river-toggle{bottom:12px}}
@media (max-width:899px),(prefers-reduced-motion:reduce){.art-river,.river-toggle{display:none}}
@media (forced-colors:active){.art-river{display:none}.river-toggle{border:1px solid ButtonText}}