/* styles.css */
:root{
  --bg0:#040c18;
  --bg1:#071224;

  --panel:#0a1930;
  --card:#081727;
  --border:#14304a;

  --text:#e8eef7;
  --muted:#a7b7cc;

  --accent:#2dd4bf;
  --accent2:#60a5fa;

  /* Nav distinct colours */
  --nav-bg: #0d1f3c;
  --nav-border: #1e3a5f;

  /* Diagram knobs */
  --diag-right-width: 45%;
  --diag-left-minh: 260px;
}

*{ box-sizing:border-box; }
html{ scroll-behavior:smooth; }

body{
  margin:0;
  font-family:-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  line-height:1.7;

  background:
    radial-gradient(800px 600px at 5% 85%, rgba(45,212,191,0.11), transparent 65%),
    radial-gradient(900px 700px at 88% 12%, rgba(45,212,191,0.18), transparent 68%),
    radial-gradient(1000px 800px at 12% 8%, rgba(96,165,250,0.22), transparent 65%),
    radial-gradient(700px 500px at 80% 55%, rgba(20,184,166,0.09), transparent 60%),
    radial-gradient(1200px 900px at 50% 95%, rgba(30,64,175,0.18), transparent 70%),
    radial-gradient(600px 400px at 100% 40%, rgba(34,211,238,0.07), transparent 55%),
    linear-gradient(180deg, #040c18 0%, #071224 50%, #040d1a 100%);

  color:var(--text);
  -webkit-font-smoothing:antialiased;
}

a{ color:inherit; }

.container{
  max-width:1040px;
  margin:0 auto;
  padding:72px 24px;
}

/* NAV */
nav{
  position:fixed;
  top:0;
  width:100%;
  z-index:1000;
  background: var(--nav-bg);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--nav-border);
  box-shadow: 0 1px 0 rgba(45,212,191,0.18), 0 4px 24px rgba(0,0,0,0.45);
}

nav::before{
  content:'';
  position:absolute;
  top:0;
  left:0;
  right:0;
  height:2px;
  background: linear-gradient(90deg, rgba(45,212,191,0.9) 0%, rgba(96,165,250,0.7) 50%, rgba(34,211,238,0.6) 100%);
}

.nav-container{
  max-width:1100px;
  margin:0 auto;
  padding:16px 24px;
  display:flex;
  justify-content:space-between;
  align-items:center;
}

.nav-left{
  display:flex;
  align-items:center;
  gap:8px;
}

.logo{
  font-weight:650;
  letter-spacing:0.8px;
  background: linear-gradient(90deg, #2dd4bf, #60a5fa);
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
  background-clip:text;
}

.nav-links{
  display:flex;
  align-items:center;
  gap:6px;
}

.nav-links a{
  text-decoration:none;
  color:var(--muted);
  padding: 6px 12px;
  font-size:0.95rem;
  transition:0.18s ease;
  border-radius: 8px;
}
.nav-links a:hover{ color:var(--accent); }

.nav-cta{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  padding: 8px 16px;
  border-radius:8px;
  border:none;
  text-decoration:none;
  font-weight:650;
  font-size:0.95rem;
  background:linear-gradient(90deg, rgba(45,212,191,1), rgba(96,165,250,0.9));
  color:#05131f !important;
  transition:0.18s ease;
  margin-left: 8px;
}
.nav-cta:hover{ opacity:0.9; }

/* HERO */
.hero{
  padding-top:120px;
  padding-bottom:72px;
}

.hero-grid{
  display:grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap:36px;
  align-items:start;
}

.hero h1{
  font-size:3.0rem;
  line-height:1.12;
  margin:0 0 18px;
  font-weight:700;
  letter-spacing:-0.4px;
}

.subtitle{
  font-size:1.22rem;
  color:var(--muted);
  max-width:60ch;
  margin:0 0 22px;
}

.cta-row{
  display:flex;
  gap:14px;
  flex-wrap:wrap;
  margin-top:20px;
}

.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  padding:12px 16px;
  border-radius:10px;
  border:1px solid rgba(20,48,74,0.9);
  text-decoration:none;
  font-weight:650;
  transition:0.18s ease;
}

.btn-primary{
  background:linear-gradient(90deg, rgba(45,212,191,1), rgba(96,165,250,0.9));
  color:#05131f;
  border:none;
}
.btn-primary:hover{ opacity:0.9; }

.btn-secondary{
  background:rgba(8,23,39,0.6);
  color:var(--text);
}
.btn-secondary:hover{
  border-color:rgba(45,212,191,0.5);
  transform: translateY(-1px);
}

/* HERO IMAGE */
.hero-image{
  position: relative;
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

.base-image{
  width: 60%;
  max-width: 460px;
  height: auto;
  display: block;
  border-radius: 0;
  box-shadow: 0 20px 40px rgba(0,0,0,0.45);

  -webkit-mask-image:
    linear-gradient(to right, transparent 0%, black 30%, black 100%),
    linear-gradient(to bottom, transparent 0%, black 30%, black 100%);
  -webkit-mask-composite: intersect;
  mask-image:
    linear-gradient(to right, transparent 0%, black 30%, black 100%),
    linear-gradient(to bottom, transparent 0%, black 30%, black 100%);
  mask-composite: intersect;
}

.overlay-image{
  position: absolute;
  top: 40%;
  left: 40%;
  transform: translate(-50%, -50%);
  width: 55%;
  max-width: 300px;
  z-index: 3;
  pointer-events: none;
}

/* SECTIONS */
.section{ background:transparent; }

h2{
  font-size:1.75rem;
  margin:0 0 18px;
  font-weight:700;
  letter-spacing:-0.2px;
}

.kicker{
  color:var(--muted);
  margin:0 0 18px;
  max-width:80ch;
}

ul{
  padding-left:18px;
  margin:12px 0 0;
}
li{ margin:10px 0; color:var(--muted); }

/* WHO SECTION GRID */
.who-grid{
  display:grid;
  grid-template-columns: repeat(3, 1fr);
  gap:16px;
  margin-top:24px;
}

.who-card{
  background: rgba(8,23,39,0.6);
  border: 1px solid rgba(20,48,74,0.9);
  border-radius: 14px;
  padding: 18px 16px;
  display:flex;
  align-items:center;
  transition: 0.2s ease;
}

.who-card p{
  margin:0;
  color: var(--muted);
  font-weight: 500;
}

.who-card:hover{
  border-color: rgba(45,212,191,0.6);
  transform: translateY(-2px);
}

/* CONTACT */
.contact-wrap{
  display:grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap:18px;
  margin-top:18px;
}

.contact-note{
  background:rgba(8,23,39,0.55);
  border:1px solid rgba(20,48,74,0.9);
  border-radius:14px;
  padding:16px;
  color:var(--muted);
}

form{
  display:flex;
  flex-direction:column;
  gap:14px;
}

input, textarea{
  padding:14px;
  font-size:1rem;
  border-radius:12px;
  border:1px solid rgba(20,48,74,0.95);
  background:rgba(8,23,39,0.75);
  color:var(--text);
}

textarea{ min-height:140px; }
input::placeholder, textarea::placeholder{ color:#6e87a3; }

button{
  padding:13px 14px;
  font-size:1rem;
  border-radius:12px;
  border:none;
  cursor:pointer;
  font-weight:750;
  background:linear-gradient(90deg, rgba(45,212,191,1), rgba(96,165,250,0.9));
  color:#05131f;
}
button:hover{ opacity:0.92; }

/* FOOTER */
footer{
  padding:60px 20px;
  color:#6e87a3;
  text-align:center;
  font-size:0.82rem;
  line-height:1.6;
}

footer p {
  max-width:760px;
  margin:0 auto 12px;
}

footer p:last-child{ margin-bottom:0; }

section{ scroll-margin-top: 110px; }

/* RESPONSIVE (general) */
@media (max-width: 1000px){
  .who-grid{ grid-template-columns: 1fr 1fr; }
}

@media (max-width: 900px){
  .hero-grid{ grid-template-columns:1fr; }
  .hero h1{ font-size:2.3rem; }
  .contact-wrap{ grid-template-columns:1fr; }
  .nav-links a{ padding: 6px 8px; }
  .nav-cta{ margin-left: 4px; padding: 7px 12px; }
}

@media (max-width: 640px){
  .who-grid{ grid-template-columns: 1fr; }
}

strong{
  font-weight:700;
  color: var(--accent);
}

/* ── INLINE DIAGRAM ── */
.diagram-wrap{ margin: 0 0 28px; }

.diag-tabs{
  display:flex;
  gap:8px;
  margin-bottom:18px;
  flex-wrap:wrap;
}

.diag-tab{
  padding:8px 18px;
  border-radius:8px;
  border:1px solid rgba(20,48,74,0.9);
  background: rgba(8,23,39,0.6);
  color:var(--muted);
  font-size:0.88rem;
  font-weight:600;
  cursor:pointer;
  transition:0.18s ease;
  font-family:inherit;
}
.diag-tab:hover{ color:var(--accent); border-color: rgba(45,212,191,0.4); }
.diag-tab.active{
  background: linear-gradient(90deg, rgba(45,212,191,0.15), rgba(96,165,250,0.1));
  border-color: rgba(45,212,191,0.6);
  color: var(--accent);
}

/* NEW: stage holds constant height so layout doesn't jump */
.diag-stage{
  position: relative;
  width: 100%;
}

/* NEW: panels overlap and fade (no reflow) */
.diag-panel{
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;

  opacity: 0;
  visibility: hidden;
  pointer-events: none;

  transition: opacity 0.5s ease;
}

.diag-panel.active{
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

/* Desktop layout */
.diag-split{
  display:flex;
  gap:16px;
  align-items:flex-start;
}

/* min-width:0 prevents flex overflow weirdness in Chrome */
.diag-left{
  flex: 1 1 auto;
  display:flex;
  flex-direction:column;
  gap:10px;
  min-width:0;
  min-height: var(--diag-left-minh);
}

/* Keeps result boxes aligned across tabs on desktop */
.diag-left .diag-result{
  margin-top:auto;
}

.diag-right{
  flex: 0 0 var(--diag-right-width);
  max-width: var(--diag-right-width);
  min-width: 0;
}

.diag-card{
  background: rgba(8,23,39,0.62);
  border: 1px solid rgba(20,48,74,0.9);
  border-radius: 14px;
  padding: 20px 16px 16px;
  overflow: visible;
}

.diag-card-media{ padding: 14px; }

.diagram-frame{
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: 10px;
}

.diag-img{
  position:absolute;
  top: 50%;
  transform: translateY(-50%);
  height:auto;
  display:block;
  max-width: none;
}

/* Per-image tuning */
.diag-problem{ width: 100%; left: -5%; }
.diag-a{       width: 100%; left: -5%; }
.diag-b{       width: 100%; left: -5%; }

.diag-result{
  padding: 10px 14px;
  border-radius: 10px;
  font-size: 0.85rem;
  color: var(--muted);
  line-height: 1.55;
  background: rgba(52,211,153,0.05);
  border: 1px solid rgba(52,211,153,0.18);
}

.diag-result-red{
  background: rgba(248,113,113,0.06);
  border: 1px solid rgba(248,113,113,0.18);
}

/* Mobile: stack Text → Diagram → Result, without changing diagram sizing model */
@media (max-width: 900px){
  .diag-split{
    flex-direction: column;
    align-items: stretch;
  }

  .diag-left{
    min-height: 0;
  }

  .diag-right{
    max-width: 100%;
    width: 100%;
    flex: 0 0 auto;
  }

  .diag-right{ order: 2; }
  .diag-left .diag-result{
    order: 3;
    margin-top: 12px;
  }
}