/* ===================================================
   KOSSOH MESSENGER — PREMIUM LANDING PAGE
   Palette : Noir profond / Or / Orange Kossoh
   =================================================== */

/* --- BASE --- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:'Inter',system-ui,-apple-system,sans-serif;
  background:#060503;
  color:#fff;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
img{max-width:100%;display:block}
a{text-decoration:none;color:inherit}

.wrap{
  max-width:1240px;
  margin:0 auto;
  padding:0 32px;
}

/* --- TYPO --- */
h1{font-size:clamp(2.8rem,6vw,5rem);font-weight:900;line-height:1;letter-spacing:-2px}
h1 em{font-style:normal;background:linear-gradient(90deg,#fde68a,#f59e0b,#ea580c);-webkit-background-clip:text;-webkit-text-fill-color:transparent}
h2{font-size:clamp(2rem,4vw,3rem);font-weight:800;line-height:1.15;letter-spacing:-1px;margin-bottom:20px}
h3{font-size:1.2rem;font-weight:700;margin-bottom:10px;color:#f5e6d0}
h4{font-size:1.1rem;font-weight:700;margin-bottom:8px;color:#f5e6d0}

.kicker{
  display:inline-flex;align-items:center;gap:10px;
  font-size:.78rem;font-weight:700;letter-spacing:2.5px;text-transform:uppercase;
  color:#f59e0b;margin-bottom:18px;
}
.kicker.center{justify-content:center;width:100%;text-align:center}
.dot{width:8px;height:8px;border-radius:50%;background:#f59e0b;display:inline-block;box-shadow:0 0 12px #f59e0b88}
.sub{color:#9a8d7e;font-size:1.1rem;max-width:580px;margin:0 auto;line-height:1.7}
.lead{color:#bfb3a4;font-size:1.15rem;line-height:1.75;margin-bottom:36px}

/* --- BUTTONS --- */
.cta-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  background:linear-gradient(135deg,#f59e0b,#ea580c);
  color:#fff;font-weight:700;font-size:.95rem;
  padding:15px 32px;border-radius:14px;
  box-shadow:0 8px 30px rgba(234,88,12,.35);
  transition:transform .25s,box-shadow .25s;
}
.cta-btn:hover{transform:translateY(-3px);box-shadow:0 14px 40px rgba(234,88,12,.5)}
.cta-btn.sm{padding:11px 22px;font-size:.85rem;border-radius:12px}
.cta-btn.lg{padding:18px 44px;font-size:1.1rem;border-radius:16px}

.ghost-btn{
  color:#f5e6d0;font-weight:600;font-size:.95rem;
  padding:15px 28px;border:1px solid rgba(255,255,255,.15);border-radius:14px;
  transition:background .2s,border-color .2s;
}
.ghost-btn:hover{background:rgba(255,255,255,.06);border-color:rgba(255,255,255,.3)}

/* --- NAVBAR --- */
nav{
  position:fixed;top:0;left:0;right:0;z-index:999;
  height:72px;
  background:rgba(6,5,3,.85);
  backdrop-filter:blur(16px);
  border-bottom:1px solid rgba(255,255,255,.06);
}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:100%}
.brand{display:flex;align-items:center;gap:10px}
.brand-icon{height:46px}
.brand-word{height:26px;filter:invert(1);opacity:.9;margin-left:4px}
.nav-links{display:flex;gap:32px}
.nav-links a{font-size:.9rem;font-weight:500;color:#c9baa9;transition:color .2s}
.nav-links a:hover{color:#fff}

/* --- HERO --- */
.hero{
  position:relative;
  min-height:100vh;
  display:flex;align-items:center;
  padding-top:72px;
  overflow:hidden;
}
.hero-bg{
  position:absolute;inset:0;width:100%;height:100%;
  object-fit:cover;
  opacity:.45;
}
.hero-overlay{
  position:absolute;inset:0;
  background:linear-gradient(180deg,rgba(6,5,3,.5) 0%,rgba(6,5,3,.95) 85%,#060503 100%);
}
.hero-grid{
  position:relative;z-index:2;
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:60px;
  align-items:center;
  padding:60px 0 100px;
}
.hero-text{max-width:560px}

.btn-row{display:flex;gap:14px;margin-bottom:40px}

.store-row{display:flex;gap:14px}
.store-badge{
  display:flex;align-items:center;gap:10px;
  background:rgba(255,255,255,.06);
  border:1px solid rgba(255,255,255,.12);
  padding:10px 18px;border-radius:12px;
  font-size:.82rem;cursor:pointer;
  transition:background .2s;
}
.store-badge:hover{background:rgba(255,255,255,.12)}
.store-badge small{display:block;color:#9a8d7e;font-size:.65rem;line-height:1.2}
.store-badge strong{display:block;font-size:.9rem;line-height:1.2}

/* Phones stack */
.hero-phones{position:relative;height:580px;display:flex;justify-content:center;align-items:center}
.phone-stack{position:relative;width:100%;height:100%;display:flex;justify-content:center;align-items:center}
.device{
  position:absolute;
  width:230px;
  border-radius:32px;
  overflow:hidden;
  box-shadow:0 30px 70px rgba(0,0,0,.8),0 0 0 1px rgba(255,255,255,.08);
  border:6px solid #1a1410;
  transition:transform .5s cubic-bezier(.4,0,.2,1);
}
.device img{width:100%;height:100%;object-fit:cover}
.device.front{z-index:3;border-color:#b45309;box-shadow:0 30px 70px rgba(0,0,0,.8),0 0 40px rgba(245,158,11,.15)}
.device.back-left{z-index:2;transform:translateX(-160px) translateY(30px) rotate(-8deg) scale(.88);opacity:.7}
.device.back-right{z-index:1;transform:translateX(160px) translateY(40px) rotate(8deg) scale(.85);opacity:.55}

.mask-floating{
  position:absolute;
  width:110px;
  right:30px;bottom:20px;
  z-index:4;
  filter:drop-shadow(0 15px 30px rgba(0,0,0,.9)) drop-shadow(0 0 25px rgba(245,158,11,.25));
  animation:floatMask 7s ease-in-out infinite;
}
@keyframes floatMask{
  0%,100%{transform:translateY(0) rotate(0deg)}
  50%{transform:translateY(-18px) rotate(8deg)}
}

/* --- PROOF BAR --- */
.proof{
  border-top:1px solid rgba(255,255,255,.06);
  border-bottom:1px solid rgba(255,255,255,.06);
  background:rgba(255,255,255,.02);
  padding:40px 0;
}
.proof-row{display:flex;align-items:center;justify-content:space-around;flex-wrap:wrap;gap:30px}
.proof-item{text-align:center;opacity:0;transform:translateY(20px);transition:all .6s ease}
.proof-item.visible{opacity:1;transform:translateY(0)}
.proof-item strong{display:block;font-size:1.5rem;font-weight:800;color:#f59e0b}
.proof-item span{display:block;font-size:.85rem;color:#9a8d7e;margin-top:4px}
.proof-divider{width:1px;height:40px;background:rgba(255,255,255,.08)}

/* --- FEATURES --- */
.features-section{padding:120px 0}
.section-intro{text-align:center;margin-bottom:70px;opacity:0;transform:translateY(30px);transition:all .7s ease}
.section-intro.visible{opacity:1;transform:translateY(0)}
.section-intro h2{color:#fff}

.cards-row{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-bottom:24px}
.card{
  background:linear-gradient(160deg,#140f0a,#0e0a06);
  border:1px solid rgba(255,255,255,.06);
  border-radius:24px;
  padding:36px 28px;
  transition:transform .35s,border-color .35s,box-shadow .35s;
  opacity:0;transform:translateY(40px);
}
.card.visible{opacity:1;transform:translateY(0)}
.card:hover{
  transform:translateY(-8px);
  border-color:rgba(245,158,11,.35);
  box-shadow:0 20px 50px rgba(0,0,0,.5),0 0 30px rgba(245,158,11,.08);
}
.card-img{
  width:64px;height:64px;border-radius:16px;overflow:hidden;
  margin-bottom:24px;
  border:1px solid rgba(255,255,255,.08);
  box-shadow:0 4px 12px rgba(0,0,0,.4);
}
.card-img img{width:100%;height:100%;object-fit:cover}
.card p{color:#9a8d7e;font-size:.93rem;line-height:1.65}

/* --- SPLIT (Privacy) --- */
.split-section{
  padding:120px 0;
  background:linear-gradient(180deg,#060503,#0d0906,#060503);
}
.split-grid{
  display:grid;grid-template-columns:1fr 1fr;gap:80px;align-items:center;
}
.split-visual{
  position:relative;
  display:flex;justify-content:center;
  opacity:0;transform:translateX(-40px);transition:all .8s ease;
}
.split-visual.visible{opacity:1;transform:translateX(0)}
.split-phone{
  width:280px;border-radius:32px;
  box-shadow:0 30px 70px rgba(0,0,0,.7),0 0 0 1px rgba(255,255,255,.08);
  border:5px solid #1a1410;
}
.split-mask{
  position:absolute;
  width:90px;top:-20px;left:20px;
  filter:drop-shadow(0 10px 20px rgba(0,0,0,.8));
  transform:rotate(-15deg);
}
.split-text{opacity:0;transform:translateX(40px);transition:all .8s ease}
.split-text.visible{opacity:1;transform:translateX(0)}
.split-text h2{color:#fff}
.split-text p{color:#9a8d7e;font-size:1.05rem;line-height:1.7;margin-bottom:20px}

.check-list{list-style:none;display:flex;flex-direction:column;gap:14px;margin-top:24px}
.check-list li{
  display:flex;align-items:center;gap:12px;
  font-size:.95rem;color:#c9baa9;
}
.check-list li::before{
  content:"✓";
  display:flex;align-items:center;justify-content:center;
  width:28px;height:28px;border-radius:50%;flex-shrink:0;
  background:rgba(245,158,11,.15);
  color:#f59e0b;font-weight:700;font-size:.8rem;
}

/* --- GALLERY --- */
.gallery-section{padding:120px 0}
.gallery-strip{
  display:flex;
  justify-content:center;
  align-items:center;
  gap:20px;
  margin-top:60px;
  overflow-x:auto;
  padding-bottom:20px;
}
.gallery-phone{
  flex-shrink:0;
  width:200px;
  border-radius:28px;
  overflow:hidden;
  border:5px solid #1a1410;
  box-shadow:0 20px 50px rgba(0,0,0,.6);
  opacity:0;transform:scale(.9) translateY(20px);transition:all .6s ease;
}
.gallery-phone.visible{opacity:.6;transform:scale(.95) translateY(0)}
.gallery-phone.featured{
  width:240px;
  border-color:#b45309;
  box-shadow:0 25px 60px rgba(0,0,0,.7),0 0 30px rgba(245,158,11,.12);
}
.gallery-phone.featured.visible{opacity:1;transform:scale(1) translateY(0)}
.gallery-phone img{width:100%;display:block}

/* --- WHY SECTION --- */
.why-section{
  padding:120px 0;
  background:linear-gradient(180deg,#060503,#0c0906);
  border-top:1px solid rgba(255,255,255,.04);
}
.why-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:30px;margin-top:60px}
.why-card{
  text-align:center;
  padding:40px 28px;
  border-radius:24px;
  background:rgba(255,255,255,.02);
  border:1px solid rgba(255,255,255,.06);
  transition:transform .35s,border-color .35s;
  opacity:0;transform:translateY(30px);
}
.why-card.visible{opacity:1;transform:translateY(0)}
.why-card:hover{transform:translateY(-6px);border-color:rgba(245,158,11,.3)}
.why-icon{
  width:70px;height:70px;border-radius:50%;overflow:hidden;
  margin:0 auto 20px;
  border:2px solid rgba(245,158,11,.25);
  box-shadow:0 0 20px rgba(245,158,11,.1);
}
.why-icon img{width:100%;height:100%;object-fit:cover}
.why-card p{color:#9a8d7e;font-size:.9rem;line-height:1.6}

/* --- DOWNLOAD CTA --- */
.download-section{
  position:relative;
  margin:0 32px 80px;
  border-radius:32px;
  overflow:hidden;
  max-width:1240px;
  margin-left:auto;margin-right:auto;
}
.download-bg{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:.35}
.download-overlay{
  position:absolute;inset:0;
  background:linear-gradient(135deg,rgba(6,5,3,.92),rgba(12,9,6,.88));
}
.download-content{
  position:relative;z-index:2;
  text-align:center;
  padding:80px 40px;
}
.download-image-large{height:250px;margin:0 auto 30px;filter:drop-shadow(0 20px 40px rgba(0,0,0,0.6)); border-radius: 20px;}
.download-content h2{color:#fff;margin-bottom:16px}
.download-content p{color:#9a8d7e;font-size:1.15rem;margin-bottom:40px}
.small-note{display:block;margin-top:20px;font-size:.82rem;color:#7a6e60}

/* --- FOOTER --- */
footer{
  border-top:1px solid rgba(255,255,255,.06);
  padding:40px 0;
}
.footer-inner{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:20px}
.footer-brand{display:flex;align-items:center;gap:10px;font-weight:600;color:#9a8d7e;font-size:.9rem}
.footer-links{display:flex;gap:24px}
.footer-links a{font-size:.85rem;color:#6e6358;transition:color .2s}
.footer-links a:hover{color:#f59e0b}
.footer-copy{font-size:.8rem;color:#4a4239;width:100%;text-align:center;margin-top:16px}

/* --- RESPONSIVE --- */
@media(max-width:960px){
  .nav-links{display:none}
  .hero-grid{grid-template-columns:1fr;text-align:center;gap:40px}
  .hero-text{max-width:100%}
  .btn-row,.store-row{justify-content:center}
  .hero-phones{height:420px}
  .device{width:180px}
  .device.back-left{transform:translateX(-100px) translateY(20px) rotate(-8deg) scale(.85)}
  .device.back-right{transform:translateX(100px) translateY(25px) rotate(8deg) scale(.82)}
  .mask-floating{width:80px;right:10px;bottom:10px}
  
  .cards-row{grid-template-columns:1fr}
  .split-grid{grid-template-columns:1fr;gap:50px;text-align:center}
  .check-list{align-items:center}
  .gallery-strip{justify-content:flex-start}
  .why-grid{grid-template-columns:1fr}
  .proof-divider{display:none}
  .footer-inner{justify-content:center;text-align:center}
}

/* Stagger children transitions */
.cards-row .card:nth-child(1){transition-delay:.05s}
.cards-row .card:nth-child(2){transition-delay:.15s}
.cards-row .card:nth-child(3){transition-delay:.25s}
.why-grid .why-card:nth-child(1){transition-delay:.05s}
.why-grid .why-card:nth-child(2){transition-delay:.15s}
.why-grid .why-card:nth-child(3){transition-delay:.25s}
.gallery-strip .gallery-phone:nth-child(1){transition-delay:.05s}
.gallery-strip .gallery-phone:nth-child(2){transition-delay:.1s}
.gallery-strip .gallery-phone:nth-child(3){transition-delay:.15s}
.gallery-strip .gallery-phone:nth-child(4){transition-delay:.2s}
.gallery-strip .gallery-phone:nth-child(5){transition-delay:.25s}