.serdec-slider{
  --accent:#1b57d6; --accent2:#0ea896; --ink:#0f2138;
  position:relative;width:100%;overflow:hidden;isolation:isolate;
  font-family:'Inter',system-ui,-apple-system,sans-serif;
  background:var(--ink);
}
.serdec-slider.h-tall{height:88vh;min-height:560px}
.serdec-slider.h-medium{height:70vh;min-height:460px}
.serdec-slider.h-short{height:54vh;min-height:360px}

.serdec-slides{position:absolute;inset:0}
.serdec-slide{position:absolute;inset:0;opacity:0;visibility:hidden;transform:translateX(100%);
  transition:transform 1s cubic-bezier(.7,0,.2,1),opacity .8s ease,visibility 1s}
.serdec-slide.is-active{opacity:1;visibility:visible;transform:translateX(0);z-index:2}
.serdec-slide.is-prev{opacity:0;visibility:visible;transform:translateX(-100%);z-index:1}
/* fade mode: no horizontal movement, pure crossfade */
.serdec-slider.mode-fade .serdec-slide{transform:none}
.serdec-slider.mode-fade .serdec-slide.is-prev{transform:none}

.serdec-bg{position:absolute;inset:0;background-size:cover;background-position:center;
  transform:scale(1.12);transition:transform 7s ease-out;will-change:transform}
.serdec-slide.is-active .serdec-bg{transform:scale(1)}         /* ken burns */
.serdec-bg[data-noimg]{background:linear-gradient(130deg,var(--accent),var(--accent2))}

.serdec-overlay{position:absolute;inset:0;
  background:linear-gradient(115deg,rgba(15,11,32,.78) 0%,rgba(15,11,32,.45) 46%,rgba(15,11,32,.12) 100%)}

.serdec-inner{position:relative;z-index:3;height:100%;max-width:1180px;margin:0 auto;
  padding:0 clamp(24px,5vw,68px);display:flex;flex-direction:column;justify-content:center;color:#fff}
.serdec-eyebrow{display:inline-flex;align-items:center;gap:9px;align-self:flex-start;
  font-size:13px;font-weight:600;letter-spacing:.14em;text-transform:uppercase;
  padding:8px 15px;border:1px solid rgba(255,255,255,.28);border-radius:100px;
  background:rgba(255,255,255,.08);backdrop-filter:blur(6px);margin-bottom:22px}
.serdec-eyebrow:before{content:"✦";color:var(--accent2)}
.serdec-heading{font-family:'Fraunces',Georgia,serif;font-weight:700;
  font-size:clamp(38px,6.2vw,78px);line-height:1.02;letter-spacing:-.02em;max-width:17ch;margin:0 0 18px}
.serdec-sub{font-size:clamp(16px,1.9vw,21px);line-height:1.55;max-width:54ch;
  color:rgba(255,255,255,.9);margin:0 0 32px}
.serdec-btn{display:inline-flex;align-items:center;gap:10px;font-weight:600;font-size:16px;
  padding:15px 30px;border-radius:100px;background:#fff;color:var(--ink);
  box-shadow:0 14px 34px rgba(0,0,0,.28);transition:transform .3s cubic-bezier(.34,1.56,.64,1),box-shadow .3s;text-decoration:none}
.serdec-btn span{transition:transform .3s cubic-bezier(.34,1.56,.64,1)}
.serdec-btn:hover{transform:translateY(-3px);box-shadow:0 20px 44px rgba(108,77,246,.4);background:var(--accent);color:#fff}
.serdec-btn:hover span{transform:translateX(5px)}

/* text entrance — plays each time a slide becomes active */
.serdec-anim{opacity:0;transform:translateY(28px);filter:blur(4px)}
.serdec-slide.is-active .serdec-anim{opacity:1;transform:none;filter:none;
  transition:opacity .8s ease,transform .8s cubic-bezier(.34,1.56,.64,1),filter .8s ease}
.serdec-slide.is-active .d1{transition-delay:.15s}
.serdec-slide.is-active .d2{transition-delay:.30s}
.serdec-slide.is-active .d3{transition-delay:.45s}
.serdec-slide.is-active .d4{transition-delay:.60s}

/* arrows */
.serdec-arrow{position:absolute;top:50%;transform:translateY(-50%);z-index:6;
  width:54px;height:54px;border-radius:50%;border:1px solid rgba(255,255,255,.35);
  background:rgba(255,255,255,.1);backdrop-filter:blur(8px);color:#fff;font-size:26px;line-height:1;
  cursor:pointer;display:grid;place-items:center;transition:background .25s,transform .25s,border-color .25s}
.serdec-arrow:hover{background:#fff;color:var(--ink);border-color:#fff}
.serdec-prev{left:clamp(14px,3vw,34px)}.serdec-next{right:clamp(14px,3vw,34px)}
.serdec-prev:hover{transform:translateY(-50%) scale(1.08) translateX(-2px)}
.serdec-next:hover{transform:translateY(-50%) scale(1.08) translateX(2px)}
@media(max-width:600px){.serdec-arrow{display:none}}

/* dots */
.serdec-dots{position:absolute;bottom:30px;left:50%;transform:translateX(-50%);z-index:6;
  display:flex;gap:10px}
.serdec-dot{width:11px;height:11px;border-radius:50%;border:none;cursor:pointer;padding:0;
  background:rgba(255,255,255,.4);transition:all .3s cubic-bezier(.34,1.56,.64,1)}
.serdec-dot:hover{background:rgba(255,255,255,.7)}
.serdec-dot.is-active{background:#fff;width:30px;border-radius:6px}

/* progress bar */
.serdec-progress{position:absolute;left:0;right:0;bottom:0;height:4px;z-index:6;background:rgba(255,255,255,.16)}
.serdec-progress-bar{display:block;height:100%;width:0;
  background:linear-gradient(90deg,var(--accent),var(--accent2))}
.serdec-slider.playing .serdec-progress-bar{animation:serdec-grow linear forwards;
  animation-duration:var(--serdec-interval,5s)}
.serdec-slider.paused .serdec-progress-bar{animation-play-state:paused}
@keyframes serdec-grow{from{width:0}to{width:100%}}

.serdec-slider:focus-visible{outline:3px solid var(--accent);outline-offset:-3px}

@media(prefers-reduced-motion:reduce){
  .serdec-slide,.serdec-bg,.serdec-anim{transition:none!important;animation:none!important;
    transform:none!important;opacity:1;filter:none}
  .serdec-slide{visibility:visible}
  .serdec-slide:not(.is-active){display:none}
  .serdec-progress-bar{display:none}
}