/* =========================================================
   THE REAL AI COACH — stylesheet
========================================================= */

:root{
  --primary: #15C7C8;
  --primary-dark: #0FA8A9;
  --primary-light: #6FE3E0;
  --secondary: #0E1E25;
  --white: #FFFFFF;
  --text: #15232D;
  --text-soft: #4C5C64;
  --bg-soft: #F4FBFB;
  --line: rgba(14,30,37,0.08);

  --font-display: 'Space Grotesk', 'Manrope', sans-serif;
  --font-body: 'Manrope', sans-serif;

  --radius-lg: 28px;
  --radius-md: 20px;
  --radius-sm: 12px;

  --shadow-soft: 0 20px 50px -20px rgba(14,30,37,0.18);
  --shadow-glow: 0 10px 40px -10px rgba(21,199,200,0.45);

  --ease: cubic-bezier(.22,1,.36,1);
}

*,*::before,*::after{ box-sizing: border-box; }

html{ scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior: auto; }
  *,*::before,*::after{ animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; }
}

body{
  margin:0;
  font-family: var(--font-body);
  color: var(--text);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img{ max-width:100%; display:block; }

a{ color: inherit; text-decoration: none; }

h1,h2,h3{ font-family: var(--font-display); margin:0; }
p{ margin:0; }

.container{
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 28px;
  position: relative;
}

.skip-link{
  position:absolute; left:-999px; top:0; background:var(--secondary); color:var(--white);
  padding:12px 18px; border-radius:0 0 10px 0; z-index:999;
}
.skip-link:focus{ left:0; }

:focus-visible{
  outline: 2.5px solid var(--primary);
  outline-offset: 3px;
  border-radius: 4px;
}

/* cursor glow (desktop only, subtle) */
.cursor-glow{
  position: fixed; inset:0; pointer-events:none; z-index: 2;
  background: radial-gradient(420px circle at var(--x,50%) var(--y,30%), rgba(21,199,200,0.08), transparent 70%);
  transition: background 0.15s ease;
}
@media (max-width: 860px){ .cursor-glow{ display:none; } }

/* =========================================================
   NAVBAR
========================================================= */
.navbar{
  position: fixed; top: 16px; left: 50%; transform: translateX(-50%);
  width: min(94%, 1080px);
  z-index: 1000;
  border-radius: 999px;
  background: rgba(255,255,255,0.62);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  border: 1px solid rgba(255,255,255,0.7);
  box-shadow: 0 10px 35px -15px rgba(14,30,37,0.22);
  transition: box-shadow .4s var(--ease), background .4s var(--ease), top .4s var(--ease);
}
.navbar.scrolled{
  background: rgba(255,255,255,0.82);
  box-shadow: 0 14px 40px -12px rgba(14,30,37,0.28);
}
.navbar-inner{
  display:flex; align-items:center; justify-content:space-between;
  padding: 9px 14px 9px 18px;
}
.nav-logo{
  display:flex; align-items:center; gap:10px;
  font-family: var(--font-display); font-weight:700; font-size: 15px; letter-spacing: 0.2px;
  color: var(--secondary);
}
.nav-logo img{ width:38px; height:38px; border-radius:10px; object-fit:cover; }

.nav-links{ display:flex; align-items:center; gap: 6px; }
.nav-links a{
  position:relative;
  font-weight:600; font-size: 14.5px; color: var(--text);
  padding: 10px 18px; border-radius: 999px;
  transition: color .25s var(--ease), background .25s var(--ease);
}
.nav-links a:hover{ color: var(--secondary); background: rgba(21,199,200,0.12); }

.nav-toggle{
  display:none; flex-direction:column; justify-content:center; gap:5px;
  width:40px; height:40px; border-radius:50%; border:none; background:transparent; cursor:pointer;
}
.nav-toggle span{ width:20px; height:2px; background: var(--secondary); margin:0 auto; border-radius:2px; transition: transform .3s var(--ease), opacity .3s var(--ease); }
.nav-toggle.open span:nth-child(1){ transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2){ opacity:0; }
.nav-toggle.open span:nth-child(3){ transform: translateY(-7px) rotate(-45deg); }

@media (max-width: 760px){
  .nav-toggle{ display:flex; }
  .nav-links{
    position:absolute; top: calc(100% + 10px); left:0; right:0;
    flex-direction:column; align-items:stretch; gap:4px;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(18px);
    border-radius: 22px;
    border: 1px solid rgba(255,255,255,0.7);
    box-shadow: 0 14px 40px -12px rgba(14,30,37,0.25);
    padding: 10px;
    opacity:0; pointer-events:none; transform: translateY(-8px);
    transition: opacity .25s var(--ease), transform .25s var(--ease);
  }
  .nav-links.open{ opacity:1; pointer-events:auto; transform: translateY(0); }
  .nav-links a{ text-align:center; padding:13px; }
}

/* =========================================================
   BUTTONS
========================================================= */
.btn{
  display:inline-flex; align-items:center; gap:9px;
  font-family: var(--font-body); font-weight:700; font-size: 15px;
  padding: 15px 26px; border-radius: 999px; cursor:pointer; border:none;
  transition: transform .35s var(--ease), box-shadow .35s var(--ease), background .35s var(--ease);
}
.btn svg{ transition: transform .3s var(--ease); }
.btn-primary{
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: var(--white);
  box-shadow: var(--shadow-glow);
}
.btn-primary:hover{ transform: translateY(-3px) scale(1.015); box-shadow: 0 16px 50px -10px rgba(21,199,200,0.6); }
.btn-primary:hover svg{ transform: translateX(4px); }
.btn-ghost{
  background: rgba(14,30,37,0.05);
  color: var(--secondary);
  border: 1.5px solid rgba(14,30,37,0.12);
}
.btn-ghost:hover{ background: rgba(14,30,37,0.09); transform: translateY(-3px); }

/* =========================================================
   HERO
========================================================= */
.hero{
  position:relative;
  min-height: 100vh;
  display:flex; align-items:center; justify-content:center;
  padding: 140px 24px 100px;
  overflow:hidden;
  background: var(--white);
}
.hero-bg{ position:absolute; inset:0; z-index:0; }
.grid-overlay{
  position:absolute; inset:0;
  background-image:
    linear-gradient(to right, rgba(14,30,37,0.035) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(14,30,37,0.035) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 35%, black 30%, transparent 80%);
}
.blob{
  position:absolute; border-radius:50%; filter: blur(70px);
  opacity:.55; will-change: transform;
}
.blob-1{
  width:560px; height:560px; left:-180px; top:-160px;
  background: radial-gradient(circle at 30% 30%, var(--primary-light), var(--primary) 70%);
  animation: float-a 16s ease-in-out infinite;
}
.blob-2{
  width:460px; height:460px; right:-140px; top:60px;
  background: radial-gradient(circle at 60% 40%, #BFF4F2, var(--primary) 75%);
  animation: float-b 19s ease-in-out infinite;
  opacity:.4;
}
.blob-3{
  width:420px; height:420px; left:38%; bottom:-220px;
  background: radial-gradient(circle, var(--secondary), transparent 70%);
  opacity:.12;
  animation: float-c 22s ease-in-out infinite;
}
@keyframes float-a{ 0%,100%{ transform: translate(0,0) scale(1);} 50%{ transform: translate(40px,50px) scale(1.08);} }
@keyframes float-b{ 0%,100%{ transform: translate(0,0) scale(1);} 50%{ transform: translate(-50px,30px) scale(0.95);} }
@keyframes float-c{ 0%,100%{ transform: translate(0,0) scale(1);} 50%{ transform: translate(30px,-40px) scale(1.1);} }

.hero-content{ position:relative; z-index:1; max-width: 880px; text-align:center; margin: 0 auto; }

.hero-eyebrow{
  display:inline-flex; align-items:center; gap:8px;
  font-size: 13.5px; font-weight:700; letter-spacing: 0.06em; text-transform:uppercase;
  color: var(--primary-dark);
  background: rgba(21,199,200,0.1);
  border: 1px solid rgba(21,199,200,0.25);
  padding: 8px 16px; border-radius: 999px;
  margin-bottom: 26px;
}

.hero-title{
  font-size: clamp(2.8rem, 8vw, 6.4rem);
  line-height: 0.98;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--secondary);
}
.hero-title .line{ display:block; }
.gradient-text{
  background: linear-gradient(100deg, var(--primary-dark), var(--primary) 45%, #4FE0DE 75%, var(--primary-dark));
  background-size: 220% auto;
  -webkit-background-clip: text; background-clip:text; color:transparent;
  animation: shine 7s linear infinite;
}
@keyframes shine{ to{ background-position: -220% center; } }

.hero-subtitle{
  margin: 30px auto 0; max-width: 640px;
  font-size: clamp(1.02rem, 1.6vw, 1.2rem);
  line-height:1.6; color: var(--text-soft); font-weight:500;
}

.hero-actions{ margin-top: 42px; display:flex; gap:16px; justify-content:center; flex-wrap:wrap; }

.scroll-cue{
  position:absolute; bottom: 38px; left:50%; transform:translateX(-50%);
  display:flex; flex-direction:column; align-items:center; gap:10px;
  z-index:1;
}
.scroll-cue span{
  width: 22px; height: 36px; border-radius: 14px; border: 2px solid rgba(14,30,37,0.25);
  position:relative;
}
.scroll-cue span::after{
  content:''; position:absolute; top:7px; left:50%; transform:translateX(-50%);
  width:4px; height:8px; border-radius:3px; background: var(--primary);
  animation: scrollDot 1.8s ease-in-out infinite;
}
@keyframes scrollDot{ 0%{ opacity:1; top:7px;} 70%{ opacity:0; top:18px;} 100%{ opacity:0; top:7px;} }
.scroll-cue p{ font-size: 11px; letter-spacing: 0.12em; text-transform:uppercase; color: var(--text-soft); font-weight:700; }

/* reveal-up animation */
.reveal-up{
  opacity:0; transform: translateY(28px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
  transition-delay: var(--delay, 0s);
}
.reveal-up.in-view{ opacity:1; transform: translateY(0); }

/* =========================================================
   SECTION GENERIC
========================================================= */
section{ position:relative; padding: 130px 0; }
.eyebrow{
  display:inline-block; font-size: 13px; font-weight:800; letter-spacing:0.1em; text-transform:uppercase;
  color: var(--primary-dark); margin-bottom: 14px;
}
.eyebrow-light{ color: var(--primary-light); }
.section-title{
  font-size: clamp(2.1rem, 4.4vw, 3.2rem);
  font-weight:700; letter-spacing:-0.01em; color: var(--secondary);
  margin-bottom: 0;
  max-width: 760px;
}
.section-title-light{ color: var(--white); }

/* =========================================================
   CONCEPT
========================================================= */
.concept{
  background: var(--secondary);
  overflow:hidden;
}
.concept-bg{ position:absolute; inset:0; z-index:0; }
.concept-bg img{
  position:absolute; inset:0; width:100%; height:100%; object-fit:cover;
  filter: blur(14px) saturate(118%) brightness(0.62);
  transform: scale(1.12);
}
.concept-bg-overlay{
  position:absolute; inset:0;
  background: linear-gradient(180deg, rgba(14,30,37,0.78), rgba(14,30,37,0.9) 55%, rgba(14,30,37,0.96));
}
.bokeh{
  position:absolute; border-radius:50%;
  background: radial-gradient(circle, rgba(21,199,200,0.9), rgba(21,199,200,0) 70%);
  filter: blur(2px);
  opacity:0.55;
  animation: drift 14s ease-in-out infinite;
}
.bokeh.b1{ width:90px; height:90px; left:8%; top:18%; animation-duration: 13s; }
.bokeh.b2{ width:50px; height:50px; left:78%; top:30%; opacity:.4; animation-duration: 17s; background: radial-gradient(circle, rgba(255,255,255,0.85), transparent 70%); }
.bokeh.b3{ width:140px; height:140px; left:60%; top:70%; animation-duration: 21s; opacity:.3; }
.bokeh.b4{ width:36px; height:36px; left:25%; top:75%; opacity:.5; animation-duration: 11s; background: radial-gradient(circle, rgba(255,255,255,0.9), transparent 70%); }
.bokeh.b5{ width:70px; height:70px; left:45%; top:10%; opacity:.35; animation-duration: 19s; }
@keyframes drift{ 0%,100%{ transform: translate(0,0); } 50%{ transform: translate(24px,-26px); } }

.concept .eyebrow, .concept .section-title{ color: var(--white); position:relative; z-index:1; }
.concept .eyebrow{ color: var(--primary-light); }

.concept-grid{
  position:relative; z-index:1;
  margin-top: 56px;
  display:grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.concept-card{
  background: rgba(255,255,255,0.07);
  border: 1px solid rgba(255,255,255,0.14);
  backdrop-filter: blur(18px) saturate(140%);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  border-radius: var(--radius-lg);
  padding: 38px 30px;
  transition: transform .45s var(--ease), background .45s var(--ease), border-color .45s var(--ease);
}
.concept-card:hover{
  transform: translateY(-8px);
  background: rgba(255,255,255,0.11);
  border-color: rgba(21,199,200,0.5);
}
.concept-icon{
  width:54px; height:54px; border-radius: 16px;
  display:flex; align-items:center; justify-content:center;
  background: linear-gradient(135deg, rgba(21,199,200,0.25), rgba(21,199,200,0.05));
  color: var(--primary-light);
  margin-bottom: 22px;
}
.concept-card h3{ color: var(--white); font-size: 1.3rem; margin-bottom:10px; }
.concept-card p{ color: rgba(255,255,255,0.66); line-height:1.6; font-size: 15px; }

/* =========================================================
   EMISSIONS
========================================================= */
.emissions{ background: var(--white); }
.emissions-grid{
  margin-top: 56px;
  display:grid; grid-template-columns: repeat(3, 1fr); gap: 26px;
}
.show-card{
  border-radius: var(--radius-lg);
  overflow:hidden;
  background: var(--white);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-soft);
  transition: transform .5s var(--ease), box-shadow .5s var(--ease);
}
.show-card:hover{ transform: translateY(-10px); box-shadow: 0 30px 60px -22px rgba(14,30,37,0.28); }

.show-media{
  position:relative; aspect-ratio: 5 / 6; overflow:hidden; background: var(--secondary);
}
.show-media img{
  width:100%; height:100%; object-fit:cover;
  transition: transform .7s var(--ease);
}
.show-card:hover .show-media img{ transform: scale(1.07); }
.show-media-overlay{
  position:absolute; inset:0;
  background: linear-gradient(180deg, transparent 40%, rgba(14,30,37,0.78) 100%);
}
.show-media-soon{
  display:flex; align-items:center; justify-content:center;
}
.soon-gradient{
  position:absolute; inset:0;
  background: linear-gradient(135deg, var(--secondary), var(--primary-dark) 55%, var(--primary) 130%);
  background-size: 220% 220%;
  animation: gradientShift 8s ease infinite;
}
@keyframes gradientShift{ 0%{ background-position: 0% 50%;} 50%{ background-position: 100% 50%;} 100%{ background-position: 0% 50%;} }
.soon-badge{
  position:relative; z-index:1;
  font-family: var(--font-display); font-weight:700; font-size: 14px; letter-spacing: 0.06em; text-transform:uppercase;
  color: var(--white);
  background: rgba(255,255,255,0.16);
  border: 1px solid rgba(255,255,255,0.4);
  padding: 10px 22px; border-radius: 999px;
  backdrop-filter: blur(10px);
}

.show-body{ padding: 26px 26px 30px; }
.show-tag{
  display:inline-block; font-size: 11.5px; font-weight:800; letter-spacing: 0.08em; text-transform:uppercase;
  color: var(--primary-dark); background: rgba(21,199,200,0.1);
  padding: 5px 12px; border-radius:999px; margin-bottom: 12px;
}
.show-body h3{ font-size: 1.35rem; margin-bottom: 10px; color: var(--secondary); }
.show-body p{ color: var(--text-soft); font-size: 14.5px; line-height:1.6; }

/* =========================================================
   100K CHALLENGE
========================================================= */
.challenge{
  background: var(--secondary);
  color: var(--white);
  overflow:hidden;
}
.challenge-glow{
  position:absolute; inset:0;
  background:
    radial-gradient(540px circle at 12% 18%, rgba(21,199,200,0.35), transparent 60%),
    radial-gradient(620px circle at 88% 78%, rgba(21,199,200,0.22), transparent 60%);
  pointer-events:none;
}
.challenge-head{ max-width: 720px; position:relative; z-index:1; }
.challenge-subtitle{
  margin-top: 22px; font-size: 1.08rem; line-height:1.7; color: rgba(255,255,255,0.72); font-weight:500;
}

.timeline{
  position:relative; z-index:1;
  margin-top: 90px;
  display:grid; grid-template-columns: repeat(4, 1fr); gap: 26px;
}
.timeline-line{
  position:absolute; top:-32px; left: 12.5%; right:12.5%; height:2px;
  background: rgba(255,255,255,0.14);
  overflow:hidden;
}
.timeline-progress{
  position:absolute; inset:0 100% 0 0; background: linear-gradient(90deg, var(--primary), var(--primary-light));
  transition: right 1.4s var(--ease);
}
.timeline-progress.filled{ right:0; }

.timeline-step{
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--radius-md);
  padding: 30px 24px;
  transition: transform .4s var(--ease), background .4s var(--ease), border-color .4s var(--ease);
}
.timeline-step:hover{
  transform: translateY(-6px);
  background: rgba(255,255,255,0.08);
  border-color: rgba(21,199,200,0.45);
}
.step-number{
  font-family: var(--font-display); font-weight:700; font-size: 2rem;
  background: linear-gradient(135deg, var(--primary-light), var(--primary));
  -webkit-background-clip:text; background-clip:text; color:transparent;
  margin-bottom: 14px;
}
.timeline-step h3{ font-size: 1.08rem; margin-bottom:8px; }
.timeline-step p{ color: rgba(255,255,255,0.62); font-size: 14px; line-height:1.55; }

/* =========================================================
   SOCIAL
========================================================= */
.social{ background: var(--bg-soft); }
.social-grid{
  margin-top: 56px;
  display:grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.social-card{
  position:relative;
  display:block;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 36px 30px 32px;
  box-shadow: var(--shadow-soft);
  transition: transform .45s var(--ease), box-shadow .45s var(--ease), border-color .45s var(--ease);
  overflow:hidden;
}
.social-card::before{
  content:''; position:absolute; inset:0; opacity:0;
  background: linear-gradient(135deg, rgba(21,199,200,0.08), transparent 60%);
  transition: opacity .4s var(--ease);
}
.social-card:hover{ transform: translateY(-8px); box-shadow: 0 28px 56px -20px rgba(14,30,37,0.25); border-color: rgba(21,199,200,0.35); }
.social-card:hover::before{ opacity:1; }
.social-icon{
  width:56px; height:56px; border-radius:16px;
  display:flex; align-items:center; justify-content:center;
  background: linear-gradient(135deg, rgba(21,199,200,0.16), rgba(21,199,200,0.04));
  color: var(--primary-dark);
  margin-bottom: 22px;
  transition: transform .4s var(--ease);
}
.social-card:hover .social-icon{ transform: scale(1.08) rotate(-4deg); }
.social-card h3{ font-size:1.25rem; color: var(--secondary); margin-bottom: 8px; }
.social-card p{ color: var(--text-soft); font-size: 14.5px; line-height:1.6; }
.social-arrow{
  position:absolute; top:32px; right:30px;
  font-size: 1.3rem; color: var(--primary-dark);
  opacity:0; transform: translate(-6px,6px);
  transition: opacity .35s var(--ease), transform .35s var(--ease);
}
.social-card:hover .social-arrow{ opacity:1; transform:translate(0,0); }

/* =========================================================
   CONTACT
========================================================= */
.contact{ background: var(--white); }
.contact-card{
  position:relative;
  background: linear-gradient(135deg, var(--secondary), #122c35 60%, #0c1b21);
  border-radius: var(--radius-lg);
  padding: 60px 50px;
  display:flex; align-items:center; justify-content:space-between; gap:40px; flex-wrap:wrap;
  overflow:hidden;
  box-shadow: var(--shadow-soft);
}
.contact-card::before{
  content:''; position:absolute; width:380px; height:380px; border-radius:50%;
  background: radial-gradient(circle, rgba(21,199,200,0.45), transparent 70%);
  right:-120px; top:-140px; filter: blur(10px);
  animation: float-a 14s ease-in-out infinite;
}
.contact-text{ position:relative; z-index:1; }
.contact .eyebrow{ color: var(--primary-light); }
.contact .section-title{ color: var(--white); }
.contact-lead{ margin-top: 16px; color: rgba(255,255,255,0.68); font-size: 1.02rem; max-width: 360px; }

.contact-info{ position:relative; z-index:1; display:flex; flex-direction:column; gap: 14px; }
.contact-row{
  display:flex; align-items:center; gap:14px;
  background: rgba(255,255,255,0.07);
  border: 1px solid rgba(255,255,255,0.16);
  padding: 16px 22px; border-radius: 999px;
  font-weight:600; color: var(--white); font-size:15px;
  transition: background .3s var(--ease), transform .3s var(--ease), border-color .3s var(--ease);
}
.contact-row:hover{ background: rgba(21,199,200,0.18); border-color: rgba(21,199,200,0.5); transform: translateX(4px); }
.contact-icon{
  width:34px; height:34px; border-radius:50%; display:flex; align-items:center; justify-content:center;
  background: rgba(21,199,200,0.2); color: var(--primary-light); flex-shrink:0;
}

/* =========================================================
   FOOTER
========================================================= */
.footer{
  position:relative;
  background: var(--secondary);
  color: rgba(255,255,255,0.8);
  padding-top: 70px;
  overflow:hidden;
}
.footer-glow{
  position:absolute; inset:0;
  background: radial-gradient(700px circle at 50% 0%, rgba(21,199,200,0.18), transparent 65%);
  pointer-events:none;
}
.footer-inner{
  position:relative; z-index:1;
  display:flex; align-items:center; justify-content:space-between; gap: 28px; flex-wrap:wrap;
  padding-bottom: 38px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-brand{ display:flex; align-items:center; gap:14px; }
.footer-brand img{ border-radius:10px; }
.footer-name{ font-family: var(--font-display); font-weight:700; color: var(--white); font-size: 16px; }
.footer-tagline{ color: rgba(255,255,255,0.55); font-size: 13.5px; margin-top:4px; }

.footer-links{ display:flex; gap: 26px; }
.footer-links a{ font-weight:600; font-size:14.5px; color: rgba(255,255,255,0.7); transition: color .25s var(--ease); }
.footer-links a:hover{ color: var(--primary-light); }

.footer-social{ display:flex; gap: 12px; }
.footer-social a{
  width:38px; height:38px; border-radius:50%;
  display:flex; align-items:center; justify-content:center;
  background: rgba(255,255,255,0.07); border: 1px solid rgba(255,255,255,0.14);
  color: var(--primary-light);
  transition: background .3s var(--ease), transform .3s var(--ease);
}
.footer-social a:hover{ background: rgba(21,199,200,0.25); transform: translateY(-3px); }

.footer-bottom{
  position:relative; z-index:1;
  padding: 22px 0 28px;
  display:flex; justify-content:center;
}
.footer-bottom p{ font-size: 13px; color: rgba(255,255,255,0.45); }

/* back to top */
.back-to-top{
  position: fixed; right: 22px; bottom: 22px; z-index: 900;
  width: 48px; height:48px; border-radius:50%; border:none; cursor:pointer;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: var(--white);
  box-shadow: var(--shadow-glow);
  display:flex; align-items:center; justify-content:center;
  opacity:0; pointer-events:none; transform: translateY(10px) scale(.9);
  transition: opacity .35s var(--ease), transform .35s var(--ease);
}
.back-to-top.visible{ opacity:1; pointer-events:auto; transform: translateY(0) scale(1); }
.back-to-top:hover{ transform: translateY(-4px) scale(1.05); }

/* =========================================================
   RESPONSIVE
========================================================= */
@media (max-width: 1024px){
  .concept-grid, .emissions-grid, .social-grid{ grid-template-columns: repeat(2, 1fr); }
  .timeline{ grid-template-columns: repeat(2, 1fr); row-gap: 40px; }
  .timeline-line{ display:none; }
}

@media (max-width: 768px){
  section{ padding: 96px 0; }
  .hero{ padding-top: 120px; }
  .contact-card{ padding: 44px 30px; flex-direction:column; align-items:flex-start; }
}

@media (max-width: 640px){
  .concept-grid, .emissions-grid, .social-grid{ grid-template-columns: 1fr; }
  .container{ padding: 0 20px; }
  .hero-actions{ flex-direction:column; width:100%; }
  .hero-actions .btn{ justify-content:center; width:100%; }
  .footer-inner{ flex-direction:column; align-items:flex-start; gap:24px; }
  .footer-bottom{ justify-content:flex-start; }
}

@media (max-width: 414px){
  .hero-title{ font-size: 2.5rem; }
  .section-title{ font-size: 1.75rem; }
}

@media (max-width: 375px){
  .container{ padding: 0 16px; }
  .navbar{ width: 92%; }
}