/* =========================================================
   Forever Renew Energy – Flipbook viewer
   ========================================================= */
:root{
  --navy-950:#070e1b;
  --navy-900:#0b1424;
  --navy-800:#12213d;
  --green:#22b35a;
  --green-600:#1d9b4b;
  --gold:#f5b301;
  --text:#eef3fa;
  --text-dim:rgba(238,243,250,.68);
  --glass:rgba(14,24,44,.62);
  --glass-brd:rgba(255,255,255,.10);
  --hover:rgba(255,255,255,.10);
  --radius:999px;
  --topbar-h:64px;
  --toolbar-h:86px;
  --ease:cubic-bezier(.22,.61,.36,1);
  --font:"Manrope",system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;
}
*{box-sizing:border-box}
html,body{margin:0;height:100%;overflow:hidden;background:var(--navy-900);color:var(--text);font-family:var(--font);-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer;padding:0}
svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
:focus-visible{outline:2px solid var(--green);outline-offset:2px}

/* ---------- Background ---------- */
.bg{position:fixed;inset:0;z-index:0;overflow:hidden}
.bg__img{position:absolute;inset:-60px;background:url("../pages/page-01.webp") center/cover no-repeat;filter:blur(48px) saturate(1.25);transform:scale(1.1);opacity:.55}
.bg__tint{position:absolute;inset:0;background:
  radial-gradient(ellipse 70% 60% at 50% 45%,rgba(11,20,36,.25),rgba(7,14,27,.88) 75%),
  linear-gradient(180deg,rgba(7,14,27,.55),rgba(7,14,27,.2) 40%,rgba(7,14,27,.75))}

/* ---------- Loader ---------- */
.loader{position:fixed;inset:0;z-index:100;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:18px;background:radial-gradient(circle at 50% 40%,#13284a,var(--navy-950));transition:opacity .6s var(--ease),visibility .6s}
.loader.is-done{opacity:0;visibility:hidden}
.loader__mark{width:76px;height:76px;border-radius:50%;display:grid;place-items:center;background:rgba(34,179,90,.12);box-shadow:0 0 0 1px rgba(34,179,90,.35),0 0 50px rgba(34,179,90,.25)}
.loader__turbine{width:46px;height:46px;stroke:var(--green);stroke-width:4}
.loader__turbine g{transform-origin:32px 32px;animation:spin 1.6s linear infinite}
.loader__turbine circle{fill:var(--gold);stroke:none}
.loader__title{font-weight:800;font-size:20px;letter-spacing:.02em}
.loader__bar{width:220px;height:4px;border-radius:4px;background:rgba(255,255,255,.1);overflow:hidden}
.loader__bar span{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--green),var(--gold));transition:width .25s var(--ease)}
.loader__pct{font-size:13px;color:var(--text-dim)}
@keyframes spin{to{transform:rotate(360deg)}}

/* ---------- Layout ---------- */
.app{position:relative;z-index:1;height:100%;display:flex;flex-direction:column;opacity:0;transition:opacity .8s var(--ease)}
.app.is-ready{opacity:1}

.topbar{height:var(--topbar-h);flex:none;display:flex;align-items:center;justify-content:space-between;padding:0 clamp(14px,3vw,36px);transition:transform .4s var(--ease),opacity .4s}
.brand{display:flex;align-items:center;gap:12px;color:var(--text);text-decoration:none;min-width:0}
.brand__dot{width:12px;height:12px;border-radius:50%;background:var(--green);box-shadow:0 0 0 4px rgba(34,179,90,.18),0 0 18px rgba(34,179,90,.6);flex:none}
.brand__name{font-weight:700;font-size:17px;white-space:nowrap}
.brand__name b{font-weight:800;color:var(--green)}
.brand__sep{width:1px;height:20px;background:var(--glass-brd)}
.brand__sub{font-size:14px;color:var(--text-dim);white-space:nowrap}
.topbar__actions{display:flex;gap:4px}

.icon-btn{width:42px;height:42px;border-radius:50%;display:grid;place-items:center;color:var(--text-dim);transition:background .2s,color .2s,transform .15s}
.icon-btn:hover{background:var(--hover);color:var(--text)}
.icon-btn:active{transform:scale(.92)}
.icon-btn--sm{width:36px;height:36px}

/* ---------- Stage ---------- */
.stage{position:relative;flex:1;min-height:0;display:flex}
.viewport{position:absolute;inset:8px clamp(12px,7vw,96px) 4px;overflow:visible}
.zoom-layer{position:absolute;inset:0;transform-origin:50% 50%;transition:transform .45s var(--ease);will-change:transform}
.zoom-layer.no-anim{transition:none}
.shift-layer{position:absolute;inset:0;transition:transform .9s cubic-bezier(.45,.05,.25,1)}
.shift-layer.no-anim{transition:none}
.book{position:absolute!important;inset:0;width:100%;height:100%}
.book-shadow{position:absolute;pointer-events:none;border-radius:2px;
  box-shadow:0 30px 60px -12px rgba(0,0,0,.65),0 18px 36px -18px rgba(0,0,0,.55),0 0 0 1px rgba(0,0,0,.08);
  transition:left .9s cubic-bezier(.45,.05,.25,1),width .9s cubic-bezier(.45,.05,.25,1),opacity .4s}

/* pages */
.page{background:#fff;overflow:hidden;user-select:none;-webkit-user-select:none}
.page img{display:block;width:100%;height:100%;object-fit:cover;pointer-events:none;-webkit-user-drag:none}
.page__shade{position:absolute;inset:0;pointer-events:none}
/* soft binding crease & page curvature light */
.page.--left .page__shade{background:linear-gradient(to left,rgba(0,0,0,.22) 0,rgba(0,0,0,.08) 2.5%,rgba(0,0,0,0) 7%,rgba(255,255,255,0) 85%,rgba(255,255,255,.06) 100%)}
.page.--right .page__shade{background:linear-gradient(to right,rgba(0,0,0,.22) 0,rgba(0,0,0,.08) 2.5%,rgba(0,0,0,0) 7%,rgba(255,255,255,0) 85%,rgba(255,255,255,.06) 100%)}
.book.--portrait .page .page__shade,.page.is-cover .page__shade{background:linear-gradient(to right,rgba(0,0,0,.12),rgba(0,0,0,0) 3%)}
.page.is-back.--left .page__shade{background:linear-gradient(to left,rgba(0,0,0,.12),rgba(0,0,0,0) 3%)}

/* zoom pan */
.pan-layer{position:absolute;inset:0;display:none;cursor:grab;touch-action:none}
.pan-layer.is-active{display:block}
.pan-layer.is-grabbing{cursor:grabbing}

/* arrows */
.nav-arrow{position:absolute;top:50%;z-index:5;width:54px;height:54px;margin-top:-27px;border-radius:50%;display:grid;place-items:center;
  background:var(--glass);border:1px solid var(--glass-brd);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  color:var(--text);transition:opacity .3s,transform .2s var(--ease),background .2s}
.nav-arrow svg{width:26px;height:26px}
.nav-arrow:hover{background:rgba(34,179,90,.85);border-color:transparent}
.nav-arrow:active{transform:scale(.92)}
.nav-arrow--prev{left:clamp(8px,2vw,28px)}
.nav-arrow--next{right:clamp(8px,2vw,28px)}
.nav-arrow[disabled]{opacity:0;pointer-events:none}

/* hint */
.hint{position:fixed;left:50%;top:13px;transform:translate(-50%,-8px);z-index:30;display:flex;align-items:center;gap:10px;
  padding:9px 16px;border-radius:var(--radius);background:var(--glass);border:1px solid var(--glass-brd);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  font-size:13px;color:var(--text-dim);opacity:0;pointer-events:none;transition:opacity .5s,transform .5s var(--ease);white-space:nowrap}
.hint.is-show{opacity:1;transform:translate(-50%,0)}
.hint__hand{width:8px;height:8px;border-radius:50%;background:var(--gold);box-shadow:0 0 0 0 rgba(245,179,1,.6);animation:pulse 1.6s infinite}
@keyframes pulse{70%{box-shadow:0 0 0 10px rgba(245,179,1,0)}100%{box-shadow:0 0 0 0 rgba(245,179,1,0)}}

/* ---------- Toolbar ---------- */
.toolbar-wrap{flex:none;height:var(--toolbar-h);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;padding:0 12px 6px;transition:transform .4s var(--ease),opacity .4s}
.progress{width:min(520px,80vw);height:3px;border-radius:3px;background:rgba(255,255,255,.1);overflow:hidden}
.progress span{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--green),var(--gold));transition:width .6s var(--ease)}
.toolbar{display:flex;align-items:center;gap:2px;padding:5px 8px;border-radius:var(--radius);background:var(--glass);border:1px solid var(--glass-brd);
  backdrop-filter:blur(18px) saturate(1.3);-webkit-backdrop-filter:blur(18px) saturate(1.3);box-shadow:0 12px 32px rgba(0,0,0,.35)}
.tb-btn{width:40px;height:40px;border-radius:50%;display:grid;place-items:center;color:var(--text-dim);transition:background .2s,color .2s,transform .15s}
.tb-btn:hover{background:var(--hover);color:var(--text)}
.tb-btn:active{transform:scale(.9)}
.tb-btn[disabled]{opacity:.3;pointer-events:none}
.tb-btn.is-on{background:var(--green);color:#fff}
.tb-sep{width:1px;height:22px;background:var(--glass-brd);margin:0 6px}
.pager{min-width:86px;height:34px;padding:0 12px;border-radius:var(--radius);display:flex;align-items:center;justify-content:center;gap:5px;font-weight:700;font-size:14px;font-variant-numeric:tabular-nums;background:rgba(255,255,255,.06);transition:background .2s}
.pager:hover{background:rgba(255,255,255,.12)}
.pager__total{color:var(--text-dim);font-weight:600}
.pager-form input{width:86px;height:34px;border-radius:var(--radius);border:1px solid var(--green);background:rgba(0,0,0,.3);color:var(--text);text-align:center;font:700 14px var(--font);outline:none;-moz-appearance:textfield}
.pager-form input::-webkit-outer-spin-button,.pager-form input::-webkit-inner-spin-button{-webkit-appearance:none;margin:0}

/* ---------- Drawer ---------- */
.drawer{position:fixed;left:50%;bottom:calc(var(--toolbar-h) + 4px);z-index:20;width:min(1100px,calc(100vw - 24px));transform:translate(-50%,24px);opacity:0;visibility:hidden;
  border-radius:20px;background:rgba(10,18,34,.86);border:1px solid var(--glass-brd);backdrop-filter:blur(22px);-webkit-backdrop-filter:blur(22px);
  box-shadow:0 24px 60px rgba(0,0,0,.5);transition:transform .4s var(--ease),opacity .3s,visibility .4s}
.drawer.is-open{transform:translate(-50%,0);opacity:1;visibility:visible}
.drawer__head{display:flex;align-items:center;justify-content:space-between;padding:10px 10px 0 20px}
.drawer__title{font-weight:700;font-size:14px;color:var(--text-dim);letter-spacing:.06em;text-transform:uppercase}
.drawer__track{display:flex;gap:18px;overflow-x:auto;padding:12px 20px 18px;scroll-snap-type:x proximity;scrollbar-width:thin;scrollbar-color:rgba(255,255,255,.2) transparent}
.thumb{flex:none;display:flex;flex-direction:column;align-items:center;gap:8px;scroll-snap-align:center;padding:6px;border-radius:12px;transition:background .2s}
.thumb:hover{background:rgba(255,255,255,.06)}
.thumb__imgs{display:flex;height:112px;box-shadow:0 6px 16px rgba(0,0,0,.4);border-radius:3px;overflow:hidden;outline:2px solid transparent;outline-offset:3px;transition:outline-color .2s,transform .25s var(--ease)}
.thumb:hover .thumb__imgs{transform:translateY(-3px)}
.thumb__imgs img{height:100%;width:auto;display:block}
.thumb__label{font-size:12px;font-weight:600;color:var(--text-dim)}
.thumb.is-active .thumb__imgs{outline-color:var(--green)}
.thumb.is-active .thumb__label{color:var(--green)}

/* ---------- Toast ---------- */
.toast{position:fixed;left:50%;top:76px;z-index:50;transform:translate(-50%,-10px);padding:10px 18px;border-radius:var(--radius);background:var(--green-600);color:#fff;font-weight:600;font-size:14px;opacity:0;pointer-events:none;transition:opacity .3s,transform .3s var(--ease);box-shadow:0 8px 24px rgba(0,0,0,.35)}
.toast.is-show{opacity:1;transform:translate(-50%,0)}

/* ---------- Fullscreen / idle ---------- */
body.is-idle .topbar,body.is-idle .toolbar-wrap{opacity:.0}
body.is-idle .nav-arrow{opacity:.15}

/* ---------- Responsive ---------- */
@media (max-width:900px){
  .brand__sep,.brand__sub{display:none}
}
@media (max-width:640px){
  :root{--topbar-h:54px;--toolbar-h:78px}
  .hide-sm{display:none}
  .viewport{inset:6px 10px 2px}
  .nav-arrow{width:42px;height:42px;margin-top:-21px}
  .nav-arrow svg{width:22px;height:22px}
  .nav-arrow--prev{left:4px}.nav-arrow--next{right:4px}
  .brand__name{font-size:15px}
  .icon-btn{width:38px;height:38px}
  .thumb__imgs{height:92px}
  .tb-btn{width:38px;height:38px}
  .tb-sep{margin:0 3px}
}
@media (max-width:1199px){ .hint{position:absolute;top:auto;bottom:14px;transform:translate(-50%,8px)} }
@media (max-width:380px){ .hide-xs{display:none} }
@media (prefers-reduced-motion:reduce){
  .shift-layer,.book-shadow,.zoom-layer{transition:none}
}
.topbar,.toolbar-wrap{position:relative;z-index:10}
.stage.is-zoomed{overflow:hidden}

/* ---------- Short screens (phone landscape, small laptops) ---------- */
@media (max-height:620px){
  :root{--topbar-h:48px;--toolbar-h:62px}
  .progress{display:none}
  .toolbar{padding:3px 6px}
  .tb-btn{width:36px;height:36px}
  .pager{height:30px;min-width:76px}
  .icon-btn{width:36px;height:36px}
  .viewport{inset:4px clamp(56px,7vw,96px) 2px}
  .nav-arrow{width:42px;height:42px;margin-top:-21px}
  .thumb__imgs{height:80px}
}
@media (max-height:420px){
  :root{--topbar-h:40px;--toolbar-h:52px}
  .brand__name{font-size:14px}
  .brand__dot{width:9px;height:9px}
  .tb-btn{width:32px;height:32px}
  .tb-btn svg,.icon-btn svg{width:19px;height:19px}
  .hint{display:none}
}
/* large desktops: a bit more breathing room */
@media (min-width:1600px) and (min-height:900px){
  .viewport{inset:14px 110px 8px}
}