/* IntelliNotebook v15 — premium physical book (INBook engine, book.js). Themes: Light (bright white paper),
   Dark (dark-paper notebook), Reader (warm sepia paper). All decorative layers are pointer-events:none. */
:root,html[data-mode=light]{--paper:#ffffff;--grain:.045;--rule:#cfdcf3;--margin-rule:#f2a7a7;--edge-a:#f3f4f8;--edge-b:#d9dce6;
 --board-a:#2b2166;--board-b:#17123f;--board-hi:rgba(255,255,255,.10);--ribbon-a:#d0337a;--ribbon-b:#7e1d4f;--gutter:.16;--endpaper-a:#ede9fe;--endpaper-b:#fce7f3;--ink:#2b2a8c}
html[data-mode=dark]{--paper:#1b1e31;--grain:.07;--rule:rgba(148,163,255,.17);--margin-rule:rgba(244,114,182,.42);--edge-a:#2a2e48;--edge-b:#15172a;
 --board-a:#0f1124;--board-b:#06070f;--board-hi:rgba(167,139,250,.16);--ribbon-a:#f472b6;--ribbon-b:#831843;--gutter:.42;--endpaper-a:#1e1b4b;--endpaper-b:#3b0764;--ink:#c7d2fe}
html[data-mode=reader]{--paper:#f8f0dc;--grain:.085;--rule:#e0cfac;--margin-rule:#cf9b7f;--edge-a:#f1e6cc;--edge-b:#d8c7a2;
 --board-a:#5f4125;--board-b:#3c2815;--board-hi:rgba(255,236,200,.10);--ribbon-a:#8e3030;--ribbon-b:#561c1c;--gutter:.14;--endpaper-a:#efe3c6;--endpaper-b:#e6d4ad;--ink:#3b2716}

.inb-host{position:relative}
.book-area{overflow-x:clip}
.inb{position:relative;outline:none;--readW:1.5px;--leftW:8px;--open:1}
.inb:focus-visible{box-shadow:0 0 0 3px var(--accent,#22d3ee)}
.inb-scene{position:absolute;inset:0;perspective:2600px;perspective-origin:50% 45%;z-index:2}
.inb-portrait .inb-scene{perspective:1700px;perspective-origin:0 45%}
.inb-slot{position:absolute;top:0;width:var(--W);height:var(--H);overflow:hidden;touch-action:pan-y pinch-zoom}
.inb-slot-l{left:0;border-radius:3px 0 0 3px}.inb-slot-r{left:var(--W);border-radius:0 3px 3px 0}
.inb-portrait .inb-slot-r{left:0;border-radius:0 4px 4px 0}.inb-portrait .inb-slot-l{display:none}
.inb .page.inb-page,.inb .page.inb-clone,.inb .page.inb-blank{position:absolute;left:0;top:0;width:var(--W);height:var(--H);background-color:var(--paper)}
.inb .page::after{content:"";position:absolute;inset:0;background:var(--inb-noise);opacity:var(--grain);pointer-events:none;z-index:6}
html[data-mode=dark] .inb .page::after{filter:invert(1)}
.inb .page.inb-blank{background-color:var(--paper)}
.inb-store{display:none!important}
.inb-live{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
/* hardcover board, spine, page-stack edges (book progress) */
.inb-board{position:absolute;top:-8px;bottom:-10px;left:-10px;right:-10px;border-radius:5px 9px 9px 5px;z-index:0;pointer-events:none;
 background:linear-gradient(160deg,var(--board-hi),transparent 40%),linear-gradient(90deg,var(--board-a),var(--board-b) 50%,var(--board-a));
 box-shadow:0 26px 50px -24px rgba(10,8,30,.55),0 6px 14px -8px rgba(10,8,30,.4),inset 0 0 0 1px rgba(255,255,255,.06)}
.inb-board::after{content:"";position:absolute;inset:0;border-radius:inherit;background:var(--inb-noise);opacity:.22;mix-blend-mode:overlay}
.inb-spine{position:absolute;top:0;bottom:0;left:calc(50% - 8px);width:16px;background:linear-gradient(90deg,rgba(0,0,0,.35),var(--board-hi) 45%,rgba(0,0,0,.35))}
.inb-portrait .inb-board{left:-7px;right:-6px;top:-6px;bottom:-8px;border-radius:7px 6px 6px 7px}
.inb-portrait .inb-spine{left:0;width:7px;border-radius:7px 0 0 7px}
.inb-stack{position:absolute;top:3px;bottom:3px;z-index:1;pointer-events:none;background:repeating-linear-gradient(90deg,var(--edge-a) 0 1px,var(--edge-b) 1px 2px);box-shadow:0 1px 2px rgba(0,0,0,.18)}
.inb-stack-r{right:calc(-1 * var(--leftW));width:var(--leftW);border-radius:0 2px 2px 0}
.inb-stack-l{left:calc(-1 * var(--readW));width:var(--readW);border-radius:2px 0 0 2px}
.inb-portrait .inb-stack-r{right:calc(-.55 * var(--leftW));width:calc(.55 * var(--leftW))}
.inb-portrait .inb-stack-l{display:none}
/* gutter / binding shadow */
.inb-gutter{position:absolute;top:0;height:var(--H);pointer-events:none;z-index:4}
.inb-landscape .inb-gutter{left:calc(var(--W) - 48px);width:96px;background:linear-gradient(90deg,transparent,rgba(0,0,0,calc(var(--gutter) * .45)) 38%,rgba(0,0,0,var(--gutter)) 50%,rgba(0,0,0,calc(var(--gutter) * .45)) 62%,transparent),linear-gradient(90deg,transparent 49.4%,rgba(255,255,255,.18) 50%,transparent 50.6%)}
.inb-portrait .inb-gutter{left:0;width:30px;background:linear-gradient(90deg,rgba(0,0,0,calc(var(--gutter) * 1.1)),transparent)}
/* ribbon bookmark */
.inb-ribbon{position:absolute;top:calc(var(--H) - 2px);left:calc(var(--W) + 30px);width:10px;height:44px;z-index:4;pointer-events:none;transform-origin:50% calc(-1 * var(--H));
 --rib:linear-gradient(90deg,var(--ribbon-b),var(--ribbon-a) 35%,color-mix(in srgb,var(--ribbon-a),#fff 22%) 50%,var(--ribbon-a) 62%,var(--ribbon-b));filter:drop-shadow(0 2px 2px rgba(0,0,0,.25))}
.inb-ribbon i{position:absolute;inset:0;background:var(--rib);clip-path:polygon(0 0,100% 0,100% 100%,50% calc(100% - 8px),0 100%)}
.inb-ribbon i::after{content:"";position:absolute;left:0;right:0;top:0;height:5px;background:linear-gradient(rgba(0,0,0,.3),transparent)}
.inb-ribbon::before{content:"";position:absolute;left:0;right:0;top:calc(-1 * var(--H) - 4px);height:16px;background:var(--rib);border-radius:0 0 2px 2px;box-shadow:0 2px 3px rgba(0,0,0,.2)}
.inb-portrait .inb-ribbon{left:auto;right:38px}
.inb-sway .inb-ribbon{animation:inbSway 1.3s cubic-bezier(.2,.7,.3,1)}
@keyframes inbSway{20%{transform:rotate(1.6deg)}45%{transform:rotate(-1deg)}70%{transform:rotate(.45deg)}100%{transform:none}}
/* turning leaf (strip mesh) */
.inb-leaf{position:absolute;top:0;width:0;height:var(--H);transform-style:preserve-3d;z-index:3;display:none;pointer-events:none}
.inb-turning .inb-leaf{display:block}
.inb-F{position:absolute;left:0;top:0;transform-style:preserve-3d;transform-origin:0 0}
.inb-strip{position:absolute;left:0;top:0;transform-style:preserve-3d;transform-origin:0 0 0}
.inb-face{position:absolute;inset:0;overflow:hidden;backface-visibility:hidden;-webkit-backface-visibility:hidden}
.inb-back{transform:rotateY(180deg)}
.inb-wrap{position:absolute;left:0;top:0;width:var(--W);height:var(--H);transform-origin:0 0}
.inb-wrap.inb-paper{background:var(--paper)}
.inb-wrap .inb-clone{pointer-events:none}
.inb-showthrough{opacity:.075;filter:grayscale(1)}
.inb-sh,.inb-hl{position:absolute;inset:0;pointer-events:none;z-index:8;opacity:0}
.inb-sh{background:#000}
.inb-hl{background:#fff}
html[data-mode=reader] .inb-sh{background:#3a2412}
/* cast shadows on the pages below */
.inb-castclip{position:absolute;left:0;top:0;width:100%;height:var(--H);overflow:hidden;pointer-events:none;z-index:2;display:none}
.inb-turning .inb-castclip{display:block}
.inb-castF{position:absolute;top:0;width:0;height:0;transform-origin:0 0}
.inb-cast1,.inb-cast2{position:absolute;top:0;width:60px;height:2400px;opacity:0}
.inb-cast1{left:0;transform-origin:0 0;background:linear-gradient(90deg,rgba(0,0,0,.34),rgba(0,0,0,.12) 35%,transparent)}
.inb-cast2{left:-60px;transform-origin:100% 0;background:linear-gradient(270deg,rgba(0,0,0,.30),rgba(0,0,0,.08) 40%,transparent)}
html[data-mode=reader] .inb-cast1{background:linear-gradient(90deg,rgba(60,36,18,.26),transparent)}
html[data-mode=reader] .inb-cast2{background:linear-gradient(270deg,rgba(60,36,18,.24),transparent)}
.inb-dragging,.inb-dragging *{-webkit-user-select:none!important;user-select:none!important;cursor:grabbing}
.inb[data-state=peek] .inb-slot-r,.inb[data-state=peek]{cursor:grab}
/* reduced motion: short cross-fade, no movement */
.inb-fade .inb-slot{animation:inbFade .16s ease-out}
@keyframes inbFade{from{opacity:.35}to{opacity:1}}
/* hardcover cover + opening */
.inb-cover{position:absolute;top:0;width:var(--W);height:var(--H);transform-origin:0 50%;transform-style:preserve-3d;display:none;z-index:6;pointer-events:none}
.inb-closed .inb-cover{display:block}
.inb-cv-front,.inb-cv-back{position:absolute;inset:-4px -6px -4px 0;backface-visibility:hidden;-webkit-backface-visibility:hidden;border-radius:2px 9px 9px 2px;overflow:hidden}
.inb-cv-front{background:linear-gradient(90deg,var(--board-b),var(--board-a) 8%,var(--board-a));box-shadow:inset 6px 0 10px -6px rgba(0,0,0,.6)}
.inb-cv-front::before{content:"";position:absolute;left:12px;top:0;bottom:0;width:3px;background:rgba(0,0,0,.28);box-shadow:1px 0 0 rgba(255,255,255,.12);z-index:3}
.inb-coverart{position:absolute!important;left:50%;top:50%;width:410px;height:560px;margin:0!important;transform-origin:center;box-shadow:none!important;border-radius:4px 14px 14px 4px!important}
.inb-cv-gloss{position:absolute;inset:0;z-index:4;background:linear-gradient(115deg,rgba(255,255,255,.16),transparent 32%,transparent 70%,rgba(255,255,255,.06));pointer-events:none}
.inb-cv-back{transform:rotateY(180deg);background:radial-gradient(120% 80% at 20% 10%,var(--endpaper-b),transparent 60%),radial-gradient(90% 70% at 90% 90%,var(--endpaper-a),transparent 65%),var(--paper);
 opacity:calc(1 - max(0, (var(--open) - .86) * 7.2))}
.inb-cv-back i{position:absolute;inset:0;background:var(--inb-noise);opacity:.12}
.inb-cv-edge{position:absolute;top:-4px;bottom:-4px;right:-6px;width:5px;transform-origin:100% 50%;transform:rotateY(90deg);background:repeating-linear-gradient(0deg,var(--board-a) 0 2px,var(--board-b) 2px 3px)}
.inb-closed.inb-landscape .inb-slot-l,.inb-closed.inb-landscape .inb-stack-l{opacity:max(0, (var(--open) - .8) * 5)}
.inb-closed.inb-landscape .inb-board{left:calc(var(--W) * (1 - var(--open)) - 10px)}
.inb-closed .inb-ribbon{opacity:var(--open)}
.inb-closed .inb-slot-r::after{content:"";position:absolute;inset:0;z-index:9;pointer-events:none;background:linear-gradient(90deg,rgba(0,0,0,.42),rgba(0,0,0,.12) 55%,transparent);opacity:var(--cvsh,0)}
/* realistic Cornell paper per theme */
.inb .cornell{border:0;border-radius:0;background:transparent;overflow:visible}
.inb .cornell .q{background:transparent;border-right:2px solid var(--margin-rule)}
.inb .cornell .n{background:transparent}
.inb .cornell .s{background:transparent;border-top:3px double var(--margin-rule)}
.inb .cornell textarea,.inb .reflect textarea{background-image:repeating-linear-gradient(transparent 0 21px,var(--rule) 21px 22px);background-attachment:local;color:var(--text)}
@media (max-width:759.98px){.inb .cornell textarea,.inb .reflect textarea{background-image:repeating-linear-gradient(transparent 0 23px,var(--rule) 23px 24px)!important}.inb .cornell .q{border-right:0;border-bottom:2px solid var(--margin-rule)}}
/* fountain-pen ink */
.pg svg.ink path.ink-f{fill:var(--ink);stroke:none;opacity:.93}
/* low quality: fewer effects */
.q-low .inb-cast1,.q-low .inb-cast2{display:none}
.q-low .inb .page::after,.inb.q-low .page::after{opacity:calc(var(--grain) * .6)}
/* sound / ink toggles in the notebook toolbar */
.nb-book{display:inline-flex;gap:2px;align-items:center}
.nb-book .tool[aria-pressed=true]{color:var(--violet-text)}
.nb-book .tool .bl{display:none}
.nb-book .tool .ic .off{display:none}.nb-book .tool:not(.is-on) .ic .on,.bk-b:not(.is-on) .ic .on{display:none}.nb-book .tool:not(.is-on) .ic .off,.bk-b:not(.is-on) .ic .off{display:inline}
.bk-b .ic .off{display:none}
.mode-pop .bk-row{display:flex;flex-direction:column;gap:8px;border-top:1px solid var(--border);padding-top:10px}
.mode-pop .bk-btns{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.mode-pop .bk-b{width:auto;height:auto;min-height:48px;display:flex;gap:8px;align-items:center;justify-content:flex-start;padding:8px 10px;border:1px solid var(--border-strong);border-radius:12px;font-size:13px;font-weight:700;color:var(--text);text-align:left}
.mode-pop .bk-b[aria-pressed=true]{border-color:var(--violet-text);color:var(--violet-text)}
@media (max-width:1279.98px){.nb-book{display:none}.nb-mode .nb-aa{display:inline-flex;min-width:44px;align-items:center;justify-content:center}}
@media (pointer:coarse){.nb-book .tool{min-width:44px;min-height:44px}}
/* text stays selectable (copy for accessibility); only an active drag disables selection */
.flip-book.inb-host,.inb-host .inb-slot .page{-webkit-user-select:text;user-select:text}
:where(.inb-host .inb-slot *){touch-action:pan-y pinch-zoom} /* nested scroll containers (.pg, textareas) must not hand horizontal swipes to the browser */
@media (max-width:759.98px){.toolbar:has(#nbModePop:not([hidden])){backdrop-filter:none;-webkit-backdrop-filter:none;z-index:120}} /* the fixed bottom sheet must anchor to the viewport, not the blurred toolbar */