:root {
  --cream: #f0f7fa;
  --ink: #0c2340;
  --rust: #0891b2;
  --rust-dim: rgba(8,145,178,0.10);
  --sage: #3b82f6;
  --sand: #a5d8e6;
  --sand-light: #d0eef5;
  --warm-white: #f5fbfd;
  --grid: rgba(8,145,178,0.08);
  --glass: rgba(240,247,250,0.88);
}

body.dark {
  --cream: #050d1a;
  --ink: #e0f0ff;
  --rust: #38bdf8;
  --rust-dim: rgba(56,189,248,0.10);
  --sand: #1e3a5f;
  --sand-light: #0f2035;
  --warm-white: #080f1c;
  --grid: rgba(56,189,248,0.07);
  --glass: rgba(5,13,26,0.90);
}

/* dark mode theme toggle */
.theme-toggle {
  width: 36px; height: 20px; border-radius: 10px;
  background: var(--sand); border: none; cursor: none;
  position: relative; transition: background .3s;
  flex-shrink: 0;
}
.theme-toggle::after {
  content: ''; position: absolute; top: 3px; left: 3px;
  width: 14px; height: 14px; border-radius: 50%;
  background: var(--rust); transition: transform .3s;
}
body.dark .theme-toggle::after { transform: translateX(16px); }

/* dark mode - all text white/light */
body.dark .nav-link { color: var(--ink); }
body.dark .form-group label { color: rgba(224,240,255,.55); }
body.dark .checkbox-row label { color: rgba(224,240,255,.55); }
body.dark .plan-label { color: rgba(224,240,255,.5); border-top-color: var(--sand-light); }
body.dark .section-hd { color: var(--ink); border-bottom-color: var(--sand-light); }
body.dark .step-title { color: var(--ink); }
body.dark .step-desc { color: rgba(224,240,255,.4); }
body.dark .feat-title { color: var(--ink); }
body.dark .feat-desc { color: rgba(224,240,255,.45); }
body.dark .stat-lbl { color: rgba(224,240,255,.45); }
body.dark .hero-sub { color: rgba(224,240,255,.6); }
body.dark .feat { background: #080f1c; }
body.dark .feat:hover { background: #0a1525; }
body.dark .features-grid { background: #1e3a5f; }
body.dark .plan-card { background: #080f1c; border-color: var(--sand-light); }
body.dark .room-item { border-bottom-color: var(--sand-light); }
body.dark .room-bar-wrap { background: var(--sand-light); }
body.dark #model-status { color: rgba(224,240,255,.4); }
body.dark .cta-inner p { color: rgba(224,240,255,.5); }
body.dark .section { background: var(--cream); }
body.dark h2.sec-h2 { color: var(--ink); }

/* theme toggle icon */
.theme-toggle-wrap { display:flex; align-items:center; gap:8px; }
.theme-label { font-size:.6rem; letter-spacing:.1em; text-transform:uppercase; color:var(--ink); opacity:.5; }

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  background: var(--cream);
  color: var(--ink);
  font-family: 'DM Mono', monospace;
  overflow-x: hidden;
  cursor: none;
  min-height: 100vh;
  transition: background 0.5s ease, color 0.5s ease;
}
/* all elements inherit smooth transition */
*, *::before, *::after {
  transition: background-color 0.4s ease, color 0.4s ease, border-color 0.4s ease, box-shadow 0.4s ease;
}
/* except transforms and opacity which should stay snappy */
.sr, .cur, .cur-ring, canvas, input, button { transition: none; }
.sr { transition: opacity .65s ease, transform .65s ease; }
.cur { transition: width .15s, height .15s; }
.theme-toggle::after { transition: transform .4s cubic-bezier(.4,0,.2,1) !important; }
.theme-toggle { transition: background 0.4s ease !important; }

/* ── CURSOR ── */
.cur { position:fixed; width:10px; height:10px; background:var(--rust); border-radius:50%; pointer-events:none; z-index:9999; transform:translate(-50%,-50%); transition:width .15s,height .15s; }
.cur-ring { position:fixed; width:32px; height:32px; border:1.5px solid var(--rust); border-radius:50%; pointer-events:none; z-index:9998; transform:translate(-50%,-50%); opacity:.6; }
body.btn-hover .cur { width:20px; height:20px; }

/* ── GRID BG ── */
.grid-bg {
  position: fixed; inset:0; z-index:0; pointer-events:none;
  background-image: linear-gradient(var(--grid) 1px, transparent 1px), linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 44px 44px;
}

/* ── NAV ── */
nav {
  position: fixed; top:0; left:0; right:0; z-index:200;
  display: flex; align-items:center; justify-content:space-between;
  padding: 18px 48px;
  background: var(--glass); backdrop-filter:blur(14px);
  border-bottom: 1px solid var(--sand-light);
}
.nav-logo { font-family:'Syne',sans-serif; font-weight:800; font-size:1rem; letter-spacing:.1em; text-transform:uppercase; }
.nav-logo span { color:var(--rust); }
.nav-right { display:flex; align-items:center; gap:28px; }
.nav-link { font-size:.68rem; letter-spacing:.12em; text-transform:uppercase; text-decoration:none; color:var(--ink); opacity:.5; transition:opacity .2s; }
.nav-link:hover { opacity:1; }
.nav-btn { background:var(--rust); color:#fff; padding:8px 20px; font-family:'DM Mono',monospace; font-size:.68rem; letter-spacing:.1em; text-transform:uppercase; border:none; border-radius:2px; cursor:none; transition:transform .2s,box-shadow .2s; }
.nav-btn:hover { transform:translateY(-1px); box-shadow:0 6px 18px rgba(8,145,178,.3); }

/* ── HERO LAYER ── */
#hero {
  position:relative; z-index:1;
  min-height:100vh; display:flex; align-items:center; justify-content:space-between;
  padding: 120px 48px 80px; gap:60px;
}
.hero-text { flex:1; max-width:580px; }
.badge {
  display:inline-flex; align-items:center; gap:8px;
  font-size:.62rem; letter-spacing:.18em; text-transform:uppercase;
  color:var(--rust); border:1px solid var(--rust); padding:5px 14px; border-radius:2px;
  margin-bottom:32px;
  opacity:0; animation: up .7s .1s forwards;
}
.badge-dot { width:6px; height:6px; background:var(--rust); border-radius:50%; animation:pulse 2s infinite; }
@keyframes pulse { 0%,100%{opacity:1}50%{opacity:.2} }

h1.hero-h1 {
  font-family:'DM Serif Display',serif; font-size:clamp(3rem,5.5vw,6rem);
  line-height:1.02; letter-spacing:-.02em; margin-bottom:28px;
  opacity:0; animation: up .8s .2s forwards;
}
h1.hero-h1 em { font-style:italic; color:var(--rust); }
.hero-sub {
  font-size:.85rem; line-height:1.95; color:rgba(12,35,64,.6);
  max-width:460px; margin-bottom:44px;
  opacity:0; animation: up .8s .35s forwards;
}
.hero-btns { display:flex; gap:16px; opacity:0; animation: up .8s .5s forwards; }
.btn-p { background:var(--rust); color:#fff; padding:14px 32px; font-family:'DM Mono',monospace; font-size:.72rem; letter-spacing:.12em; text-transform:uppercase; text-decoration:none; border:none; border-radius:2px; cursor:none; display:inline-block; transition:transform .2s,box-shadow .2s; }
.btn-p:hover { transform:translateY(-2px); box-shadow:0 8px 24px rgba(8,145,178,.3); }
.btn-s { background:transparent; color:var(--ink); padding:14px 32px; font-family:'DM Mono',monospace; font-size:.72rem; letter-spacing:.12em; text-transform:uppercase; text-decoration:none; border:1.5px solid var(--sand); border-radius:2px; cursor:none; display:inline-block; transition:border-color .2s,transform .2s; }
.btn-s:hover { border-color:var(--ink); transform:translateY(-2px); }

/* animated canvas */
.hero-canvas-wrap {
  flex:1; max-width:500px; aspect-ratio:1;
  background:var(--warm-white); border:1.5px solid var(--sand); border-radius:4px;
  overflow:hidden; box-shadow:20px 20px 0 var(--sand-light); position:relative;
  opacity:0; animation: fadeIn 1.2s .4s forwards;
}
#heroCanvas { width:100%; height:100%; display:block; }
.canvas-label { position:absolute; bottom:14px; right:14px; font-size:.58rem; letter-spacing:.14em; text-transform:uppercase; color:rgba(12,35,64,.3); }

@keyframes up { from{opacity:0;transform:translateY(20px)} to{opacity:1;transform:none} }
@keyframes fadeIn { from{opacity:0} to{opacity:1} }

/* ── STATS BAR ── */
.stats {
  position:relative; z-index:1;
  background:#0c2340; color:#e0f0ff;
  display:flex; justify-content:space-around; padding:36px 48px;
}
.stat-num { font-family:'DM Serif Display',serif; font-size:2.4rem; color:#38bdf8; display:block; }
.stat-lbl { font-size:.62rem; letter-spacing:.15em; text-transform:uppercase; color:rgba(224,240,255,.45); margin-top:4px; }

/* ── APP LAYER — always visible in page flow ── */
#appLayer {
  position:relative; z-index:10;
  background: var(--cream);
}

/* ── APP SHELL ── */
.app-header {
  background:#0c2340; color:#e0f0ff;
  padding:32px 48px 0; display:flex; align-items:flex-start; justify-content:space-between;
  border-bottom:1px solid rgba(255,255,255,.08);
}
.app-title { font-family:'DM Serif Display',serif; font-size:2rem; }
.app-sub { font-size:.72rem; color:rgba(240,244,255,.45); letter-spacing:.1em; margin-top:4px; }
.app-qr { text-align:right; }
.app-qr-box {
  width:80px; height:80px; background:#0a1a2e; border-radius:4px;
  display:flex; align-items:center; justify-content:center;
  font-size:.5rem; text-align:center; color:#38bdf8; padding:6px;
  border:1px solid rgba(56,189,248,.2);
}

/* ── TABS ── */
.tabs {
  display:flex; background:#0c2340; padding:0 48px; gap:0;
  border-bottom:1px solid rgba(56,189,248,.1);
}
.tab {
  padding:16px 28px; font-family:'DM Mono',monospace; font-size:.68rem; letter-spacing:.12em; text-transform:uppercase;
  color:rgba(224,240,255,.4); cursor:none; border:none; background:transparent;
  border-bottom:2px solid transparent; transition:color .2s,border-color .2s; white-space:nowrap;
}
.tab.active { color:#38bdf8; border-bottom-color:#38bdf8; }
.tab:hover:not(.active) { color:rgba(224,240,255,.75); }

/* ── APP CONTENT ── */
.app-body {
  display:flex; min-height:70vh;
}
.app-main {
  flex:1; padding:48px; max-width:calc(100% - 320px);
  transition: max-width 0.4s cubic-bezier(.4,0,.2,1);
}
.app-sidebar {
  width:320px; border-left:1px solid var(--sand-light);
  display:flex; flex-direction:column;
  transition: width 0.45s cubic-bezier(.4,0,.2,1), 
              min-width 0.45s cubic-bezier(.4,0,.2,1),
              opacity 0.35s ease,
              border-color 0.45s ease;
  overflow: hidden;
  flex-shrink: 0;
  min-width: 320px;
}
.app-sidebar.collapsed {
  width: 0 !important;
  min-width: 0 !important;
  opacity: 0;
  pointer-events: none;
  border-left-color: transparent;
}
.app-main {
  flex:1; padding:48px; max-width:calc(100% - 320px);
  transition: max-width 0.45s cubic-bezier(.4,0,.2,1);
}
.app-body.chat-collapsed .app-main {
  max-width: 100%;
}

/* floating chat reopen button - appears on right edge */
.chat-reopen-btn {
  position: fixed;
  right: 0; top: 50%;
  transform: translateY(-50%) translateX(100%);
  background: var(--rust); color: #fff;
  border: none; border-radius: 6px 0 0 6px;
  padding: 14px 10px;
  font-size: .62rem; letter-spacing:.1em; text-transform:uppercase;
  font-family: 'DM Mono', monospace;
  writing-mode: vertical-rl;
  cursor: none; z-index: 300;
  box-shadow: -4px 0 20px rgba(8,145,178,.3);
  transition: transform 0.45s cubic-bezier(.4,0,.2,1), background 0.2s;
}
.chat-reopen-btn.visible {
  transform: translateY(-50%) translateX(0);
}
.chat-reopen-btn:hover { background: var(--sage); }

/* panels */
.panel { display:none; }
.panel.active { display:block; }

/* ── FORM ELEMENTS ── */
.form-row { display:grid; grid-template-columns:1fr 1fr; gap:20px; margin-bottom:20px; }
.form-row.cols3 { grid-template-columns:1fr 1fr 1fr; }
.form-group { display:flex; flex-direction:column; gap:6px; }
.form-group label {
  font-size:.62rem; letter-spacing:.12em; text-transform:uppercase;
  color:rgba(56,189,248,.7);
}
.form-group input, .form-group select {
  background:#0c2340; border:1px solid rgba(56,189,248,.25);
  border-radius:2px; padding:11px 14px;
  font-family:'DM Mono',monospace; font-size:.82rem; color:#e0f0ff;
  cursor:none; transition:border-color .2s, box-shadow .2s; outline:none;
}
.form-group input::placeholder { color:rgba(224,240,255,.3); }
.form-group input:focus, .form-group select:focus {
  border-color:#38bdf8; box-shadow:0 0 0 3px rgba(56,189,248,.12);
}
.form-group select option { background:#0c2340; color:#e0f0ff; }
.area-display {
  background:rgba(56,189,248,.08); border:1px solid rgba(56,189,248,.2);
  padding:12px 16px; border-radius:2px; font-size:.78rem;
  color:#38bdf8; margin-bottom:20px;
}
.checkbox-row { display:flex; align-items:center; gap:10px; margin-bottom:24px; }
.checkbox-row input[type=checkbox] { width:16px; height:16px; accent-color:#38bdf8; cursor:none; }
.checkbox-row label { font-size:.78rem; color:rgba(224,240,255,.55); cursor:none; }

.btn-gen {
  width:100%; background:#0891b2; color:#fff;
  border:none; padding:15px; font-family:'DM Mono',monospace;
  font-size:.75rem; letter-spacing:.14em; text-transform:uppercase;
  border-radius:2px; cursor:none; transition:transform .2s,box-shadow .2s,background .2s;
  margin-bottom:36px;
}
.btn-gen:hover { transform:translateY(-1px); box-shadow:0 8px 20px rgba(56,189,248,.3); background:#38bdf8; }
.btn-gen:disabled { opacity:.5; transform:none; box-shadow:none; }

/* section header */
.section-hd {
  font-family:'Syne',sans-serif; font-weight:700; font-size:1rem;
  margin-bottom:20px; padding-bottom:10px; border-bottom:1px solid rgba(56,189,248,.15);
  color:#e0f0ff;
}
.section-tag { font-size:.6rem; letter-spacing:.16em; text-transform:uppercase; color:#38bdf8; margin-bottom:16px; }

/* ── FLOOR PLAN GRID ── */
.plans-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:20px; margin-bottom:32px; }
.plan-card {
  background:#0a1525; border:1.5px solid rgba(56,189,248,.15); border-radius:4px;
  overflow:hidden; transition:box-shadow .2s,transform .2s,border-color .2s;
}
.plan-card:hover { box-shadow:0 8px 24px rgba(56,189,248,.12); transform:translateY(-2px); border-color:rgba(56,189,248,.35); }
.plan-canvas-wrap { position:relative; aspect-ratio:1; }
.plan-canvas-wrap canvas { width:100%; height:100%; display:block; }
.plan-label {
  padding:10px 14px; font-size:.62rem; letter-spacing:.1em; text-transform:uppercase;
  color:rgba(224,240,255,.4); border-top:1px solid rgba(56,189,248,.1);
  display:flex; justify-content:space-between; align-items:center;
  background:#080f1c;
}
.plan-dl {
  font-size:.6rem; color:#38bdf8; cursor:none; text-decoration:none;
  letter-spacing:.1em; text-transform:uppercase; border:1px solid rgba(56,189,248,.4);
  padding:3px 10px; border-radius:2px; transition:background .2s,color .2s;
}
.plan-dl:hover { background:#0891b2; color:#fff; border-color:#0891b2; }

/* ── DWELLING BADGE ── */
.dwelling-badge {
  display:inline-block; background:rgba(56,189,248,.08); color:#38bdf8;
  border:1px solid rgba(56,189,248,.25); padding:8px 18px; border-radius:2px;
  font-size:.72rem; letter-spacing:.1em; text-transform:uppercase; margin-bottom:24px;
}


/* ── 2D LAYOUT ── */
#canvas2d { width:100%; border-radius:4px; background:#080f1c; border:1.5px solid rgba(56,189,248,.15); }

/* ── SENSOR PANEL ── */
.sensor-card {
  background:#0a1525; border:1.5px solid rgba(56,189,248,.15); border-radius:4px;
  padding:24px; margin-bottom:20px;
}
.sensor-row { display:flex; align-items:center; justify-content:space-between; margin-bottom:16px; }
.sensor-val { font-family:'DM Serif Display',serif; font-size:2rem; color:#38bdf8; }
.sensor-unit { font-size:.65rem; letter-spacing:.1em; text-transform:uppercase; color:rgba(224,240,255,.4); margin-top:4px; }
.sensor-grid { display:grid; grid-template-columns:1fr 1fr; gap:12px; margin-bottom:20px; }
.sensor-mini { background:#0a1525; border:1.5px solid rgba(56,189,248,.15); border-radius:4px; padding:18px; }
.sensor-mini-lbl { font-size:.6rem; letter-spacing:.12em; text-transform:uppercase; color:rgba(224,240,255,.4); margin-bottom:8px; }
.indicator { display:inline-flex; align-items:center; gap:6px; font-size:.75rem; color:#e0f0ff; }
.dot-on { width:8px; height:8px; border-radius:50%; background:#5a8a6a; animation:pulse 1.5s infinite; }
.dot-off { width:8px; height:8px; border-radius:50%; background:rgba(56,189,248,.2); }
.btn-sensor {
  background:transparent; color:#e0f0ff; border:1.5px solid rgba(56,189,248,.3);
  padding:12px 20px; font-family:'DM Mono',monospace; font-size:.7rem; letter-spacing:.1em; text-transform:uppercase;
  border-radius:2px; cursor:none; transition:all .2s; margin-right:10px; margin-bottom:10px;
}
.btn-sensor:hover { border-color:var(--ink); background:var(--ink); color:var(--cream); }
.btn-sensor.danger { border-color:var(--rust); color:var(--rust); }
.btn-sensor.danger:hover { background:var(--rust); color:#fff; }
.sensor-status { font-size:.72rem; color:rgba(12,35,64,.5); padding:10px 0; }
.dim-confirmed { display:grid; grid-template-columns:1fr 1fr; gap:16px; margin-bottom:20px; }
.dim-box { background:var(--ink); color:var(--cream); padding:18px; border-radius:4px; text-align:center; }
.dim-box-val { font-family:'DM Serif Display',serif; font-size:1.8rem; }
.dim-box-lbl { font-size:.6rem; letter-spacing:.12em; text-transform:uppercase; opacity:.4; margin-top:4px; }

/* ── ROOM LIST ── */
.room-list { margin-bottom:28px; }
.room-item {
  display:flex; align-items:center; justify-content:space-between;
  padding:12px 16px; border-bottom:1px solid var(--sand-light);
  font-size:.78rem;
}
.room-item:last-child { border-bottom:none; }
.room-name { text-transform:capitalize; }
.room-area { color:var(--rust); font-weight:500; }
.room-bar-wrap { flex:1; margin:0 16px; height:4px; background:var(--sand-light); border-radius:2px; overflow:hidden; }
.room-bar { height:100%; background:var(--rust); border-radius:2px; }

/* ── RADIO GROUP ── */
.radio-group { display:flex; gap:10px; margin-bottom:20px; flex-wrap:wrap; }
.radio-opt {
  padding:8px 18px; border:1.5px solid var(--sand); border-radius:2px;
  font-size:.7rem; letter-spacing:.1em; text-transform:uppercase; cursor:none;
  transition:all .2s; user-select:none;
}
.radio-opt.selected { border-color:var(--rust); background:var(--rust-dim); color:var(--rust); }

/* ── CHATBOT ── */
.chat-header {
  background:#0c2340; color:#e0f0ff;
  padding:20px 24px; border-bottom:1px solid rgba(56,189,248,.1);
}
.chat-title { font-family:'Syne',sans-serif; font-weight:700; font-size:.9rem; color:#e0f0ff; }
.chat-sub { font-size:.62rem; color:rgba(224,240,255,.4); letter-spacing:.08em; margin-top:3px; }
.chat-msgs {
  flex:1; overflow-y:auto; padding:20px;
  display:flex; flex-direction:column; gap:14px;
  max-height:calc(100vh - 280px); min-height:200px;
  background:#080f1c;
}
.chat-msgs::-webkit-scrollbar { width:4px; }
.chat-msgs::-webkit-scrollbar-track { background:transparent; }
.chat-msgs::-webkit-scrollbar-thumb { background:#1e3a5f; border-radius:2px; }
.msg { max-width:90%; padding:12px 16px; border-radius:4px; font-size:.75rem; line-height:1.7; }
.msg.bot { background:#0f2035; color:#e0f0ff; align-self:flex-start; }
.msg.user { background:#0891b2; color:#fff; align-self:flex-end; }
.msg.typing { background:#0f2035; align-self:flex-start; display:flex; gap:4px; align-items:center; padding:14px 18px; }
.typing-dot { width:6px; height:6px; border-radius:50%; background:rgba(224,240,255,.35); animation:typingDot 1.2s infinite; }
.typing-dot:nth-child(2) { animation-delay:.2s; }
.typing-dot:nth-child(3) { animation-delay:.4s; }
@keyframes typingDot { 0%,100%{transform:translateY(0)}50%{transform:translateY(-5px)} }
.chat-input-row {
  padding:16px 20px; border-top:1px solid rgba(56,189,248,.1);
  display:flex; gap:10px; background:#0a1525;
}
.chat-input {
  flex:1; background:#0c2340; border:1px solid rgba(56,189,248,.2); border-radius:2px;
  padding:10px 14px; font-family:'DM Mono',monospace; font-size:.75rem; color:#e0f0ff;
  outline:none; cursor:none; transition:border-color .2s;
}
.chat-input::placeholder { color:rgba(224,240,255,.3); }
.chat-input:focus { border-color:#38bdf8; }
.chat-send {
  background:#0891b2; color:#fff; border:none; padding:10px 16px;
  border-radius:2px; font-family:'DM Mono',monospace; font-size:.68rem;
  letter-spacing:.1em; text-transform:uppercase; cursor:none; transition:transform .15s, background .2s;
}
.chat-send:hover { transform:scale(1.05); background:#38bdf8; }

/* ── BACK BTN — removed */

/* ── SCROLL REVEAL (bidirectional) ── */
.sr {
  opacity:0; transform:translateY(24px);
  transition: opacity .65s ease, transform .65s ease;
}
.sr.visible { opacity:1; transform:none; }
/* when scrolled past, collapse again */
.sr.past { opacity:0; transform:translateY(-16px); }

/* ── SUCCESS/INFO MESSAGES ── */
.msg-success { background:#dbeafe; border:1px solid #3b82f6; color:#1d4ed8; padding:12px 16px; border-radius:2px; font-size:.75rem; margin-bottom:16px; }
.msg-info { background:var(--rust-dim); border:1px solid rgba(8,145,178,.2); color:var(--rust); padding:12px 16px; border-radius:2px; font-size:.75rem; margin-bottom:16px; }

/* ── REMAINING SECTIONS (landing page) ── */
.section {
  position:relative; z-index:1; padding:90px 48px;
}
.sec-tag { font-size:.62rem; letter-spacing:.18em; text-transform:uppercase; color:var(--rust); margin-bottom:16px; }
h2.sec-h2 { font-family:'DM Serif Display',serif; font-size:clamp(2rem,3.5vw,3.2rem); letter-spacing:-.02em; line-height:1.1; margin-bottom:48px; }
.features-grid { display:grid; grid-template-columns:1fr 1fr; gap:2px; background:var(--sand-light); border:1.5px solid var(--sand-light); }
.feat {
  background:var(--cream); padding:44px 38px; position:relative; overflow:hidden;
  transition:background .2s;
}
.feat::before { content:''; position:absolute; top:0; left:0; width:3px; height:0; background:var(--rust); transition:height .4s; }
.feat:hover::before { height:100%; }
.feat:hover { background:var(--warm-white); }
.feat-icon { font-size:1.7rem; margin-bottom:18px; display:block; }
.feat-title { font-family:'Syne',sans-serif; font-weight:700; font-size:1rem; margin-bottom:10px; }
.feat-desc { font-size:.76rem; line-height:1.9; color:rgba(12,35,64,.55); }

.steps-row {
  display: grid; grid-template-columns: repeat(4,1fr);
  gap: 0; margin-top: 0; position: relative;
}
/* connector line — between steps only, not extending past circle 4 */
.steps-row::before { display: none; }
.step-item { padding: 0 0 0 0; position: relative; }
.step-item:last-child { padding-right: 0; }
/* line drawn from right edge of circle to the next circle's left edge */
.step-item:not(:last-child)::after {
  content: '';
  position: absolute;
  top: 26px;
  left: 52px;
  width: calc(100% - 52px);
  height: 1px;
  background: rgba(8,145,178,0.35);
  z-index: 0;
}
.step-item { padding: 0 28px 0 0; position: relative; }
.step-item:last-child { padding-right: 0; }
.step-num {
  width: 52px; height: 52px; border-radius: 50%;
  border: 1.5px solid var(--rust);
  display: flex; align-items: center; justify-content: center;
  font-family: 'DM Serif Display', serif; font-size: 1.1rem; color: var(--rust);
  margin-bottom: 32px; background: #0c2340;
  position: relative; z-index: 1;
  flex-shrink: 0;
}
.step-title {
  font-family: 'Syne', sans-serif; font-weight: 700; font-size: .95rem;
  margin-bottom: 10px; color: var(--cream);
}
.step-desc { font-size: .72rem; line-height: 1.85; color: rgba(240,244,255,.4); font-family: 'DM Mono', monospace; }

.tech-pills { display:flex; flex-wrap:wrap; gap:10px; margin-top:32px; }
.pill { font-size:.65rem; letter-spacing:.12em; text-transform:uppercase; border:1px solid var(--sand); padding:7px 15px; border-radius:2px; transition:border-color .2s,color .2s; }
.pill:hover { border-color:var(--rust); color:var(--rust); }

/* big watermark */
.cta-section { position:relative; z-index:1; padding:120px 48px; text-align:center; overflow:hidden; }
.cta-wm { position:absolute; font-family:'DM Serif Display',serif; font-size:17vw; color:var(--sand-light); opacity:.5; white-space:nowrap; top:50%; left:50%; transform:translate(-50%,-50%); pointer-events:none; letter-spacing:-.03em; }
.cta-inner { position:relative; z-index:1; }
.cta-inner h2 { font-family:'DM Serif Display',serif; font-size:clamp(2.5rem,5vw,4.5rem); margin-bottom:20px; }
.cta-inner p { font-size:.82rem; color:rgba(12,35,64,.5); max-width:460px; margin:0 auto 44px; line-height:1.9; }

footer {
  position:relative; z-index:1; background:var(--ink); color:var(--cream);
  padding:44px 48px; display:flex; align-items:center; justify-content:space-between;
}
.footer-logo { font-family:'Syne',sans-serif; font-weight:800; font-size:.95rem; letter-spacing:.1em; text-transform:uppercase; }
.footer-logo span { color:var(--rust); }
.footer-links { display:flex; gap:24px; list-style:none; }
.footer-links a { font-size:.62rem; letter-spacing:.12em; text-transform:uppercase; color:rgba(240,244,255,.35); text-decoration:none; transition:color .2s; }
.footer-links a:hover { color:var(--cream); }
.footer-c { font-size:.6rem; color:rgba(240,244,255,.2); }

/* ══════════════════════════════════════
   RESPONSIVE — TABLET ≤900px
══════════════════════════════════════ */
@media(max-width:900px){
  nav { padding:14px 20px; }
  .nav-link { display:none; }
  .nav-right { gap:14px; }

  #hero { flex-direction:column; padding:100px 28px 56px; gap:32px; min-height:auto; }
  .hero-canvas-wrap { display:none; }
  .hero-text { max-width:100%; }

  .stats { padding:24px 20px; flex-wrap:wrap; gap:0; }
  .stat { min-width:50%; text-align:center; padding:16px 12px; }

  .section { padding:72px 28px; }
  .features-grid { grid-template-columns:1fr 1fr; }
  .steps-row { grid-template-columns:1fr 1fr; gap:36px; }
  .step-item:not(:last-child)::after { display:none; }

  .app-header { padding:24px 28px 0; }
  .tabs { padding:0 20px; overflow-x:auto; -webkit-overflow-scrolling:touch; }
  .tabs::-webkit-scrollbar { display:none; }

  .app-body { flex-direction:column; }
  .app-main { padding:28px; max-width:100% !important; }
  .app-sidebar {
    width:100% !important; min-width:0 !important;
    border-left:none !important;
    border-top:1px solid rgba(56,189,248,.1);
    transition: max-height 0.45s cubic-bezier(.4,0,.2,1), opacity 0.35s ease;
  }
  .app-sidebar.collapsed { max-height:0 !important; min-height:0 !important; overflow:hidden; opacity:0; pointer-events:none; border-top:none; }
  .chat-reopen-btn { writing-mode:horizontal-tb; right:16px; top:auto; bottom:20px; transform:translateY(80px); border-radius:4px; padding:10px 16px; }
  .chat-reopen-btn.visible { transform:translateY(0); }

  .plans-grid { grid-template-columns:1fr 1fr; }
  .form-row { grid-template-columns:1fr 1fr; }

  .cta-section { padding:80px 28px; }
  footer { padding:36px 28px; flex-direction:column; gap:20px; text-align:center; }
  .footer-links { justify-content:center; flex-wrap:wrap; }
}

/* ══════════════════════════════════════
   RESPONSIVE — PHONE ≤600px
══════════════════════════════════════ */
@media(max-width:600px){
  .cur, .cur-ring { display:none !important; }
  body { cursor:auto !important; }
  * { cursor:auto !important; }

  nav { padding:12px 16px; }
  .nav-right { gap:10px; }
  .nav-btn { padding:7px 14px; font-size:.6rem; }
  .theme-label { display:none; }

  #hero { padding:80px 16px 48px; gap:28px; }
  .hero-h1 { font-size:clamp(1.9rem,9vw,2.8rem); line-height:1.05; margin-bottom:18px; }
  .hero-sub { font-size:.78rem; margin-bottom:28px; }
  .hero-btns { flex-direction:column; gap:10px; }
  .btn-p, .btn-s { width:100%; text-align:center; padding:13px 20px; font-size:.68rem; }
  .badge { font-size:.55rem; margin-bottom:20px; }

  .stats { display:grid; grid-template-columns:1fr 1fr; padding:0; }
  .stat { padding:20px 12px; border-right:1px solid rgba(56,189,248,.1); border-bottom:1px solid rgba(56,189,248,.1); }
  .stat:nth-child(2n) { border-right:none; }
  .stat:nth-child(3), .stat:nth-child(4) { border-bottom:none; }
  .stat-num { font-size:1.8rem; }
  .stat-lbl { font-size:.55rem; }

  .section { padding:52px 16px; }
  h2.sec-h2 { font-size:clamp(1.7rem,7vw,2.4rem); margin-bottom:28px; }
  .sec-tag { font-size:.55rem; }

  .features-grid { grid-template-columns:1fr; gap:1px; }
  .feat { padding:28px 20px; }
  .feat-icon { font-size:1.4rem; margin-bottom:12px; }
  .feat-title { font-size:.9rem; }
  .feat-desc { font-size:.72rem; }

  .steps-row { grid-template-columns:1fr; gap:24px; }
  .step-item { display:flex; flex-direction:row; gap:16px; align-items:flex-start; padding-right:0; }
  .step-num { width:40px; height:40px; font-size:.9rem; margin-bottom:0; flex-shrink:0; }
  .step-title { font-size:.85rem; margin-bottom:6px; }
  .step-desc { font-size:.68rem; }

  .pill { font-size:.58rem; padding:6px 10px; }

  .app-header { padding:18px 16px 0; }
  .app-title { font-size:1.3rem; }
  .app-sub { font-size:.6rem; }
  .app-qr { display:none; }

  .tabs { padding:0 16px; }
  .tab { padding:12px 14px; font-size:.58rem; letter-spacing:.07em; }

  .app-main { padding:16px; }
  .app-sidebar { max-height:360px; }

  .form-row, .form-row.cols3 { grid-template-columns:1fr; gap:12px; margin-bottom:14px; }
  .form-group input, .form-group select { padding:11px 12px; font-size:.78rem; }
  .form-group label { font-size:.58rem; }
  .area-display { font-size:.72rem; padding:10px 12px; }
  .btn-gen { padding:13px; font-size:.68rem; margin-bottom:20px; }
  .checkbox-row label { font-size:.72rem; }

  .section-hd { font-size:.86rem; }
  .section-tag { font-size:.56rem; }

  .plans-grid { grid-template-columns:1fr; gap:14px; }

  .radio-group { flex-wrap:wrap; }
  .radio-opt { font-size:.65rem; padding:7px 14px; }

  .chat-msgs { max-height:180px; min-height:120px; }
  .chat-header { padding:14px 16px; }
  .chat-title { font-size:.82rem; }
  .chat-sub { font-size:.58rem; }
  .chat-input-row { padding:10px 12px; gap:8px; }
  .chat-input { font-size:.72rem; padding:9px 10px; }
  .chat-send { padding:9px 12px; font-size:.6rem; }

  .dwelling-badge { font-size:.65rem; padding:7px 14px; }

  .sensor-grid { grid-template-columns:1fr; }
  .sensor-card { padding:18px; }
  .sensor-val { font-size:1.6rem; }

  .cta-section { padding:56px 16px; }
  .cta-inner h2 { font-size:clamp(1.5rem,7vw,2.2rem); margin-bottom:14px; }
  .cta-inner p { font-size:.75rem; margin-bottom:28px; }
  .cta-wm { font-size:22vw; }
  .cta-btns { flex-direction:column; gap:10px; }
  .cta-btns .btn-p, .cta-btns .btn-s { width:100%; text-align:center; }

  footer { padding:28px 16px; gap:16px; }
  .footer-links { gap:14px; justify-content:center; flex-wrap:wrap; }
  .footer-links a { font-size:.58rem; }
  .footer-c { font-size:.56rem; }

  .room-item { flex-direction:column; align-items:flex-start; gap:6px; }
}

/* ══════════════════════════════════════
   RESPONSIVE — SMALL PHONE ≤380px
══════════════════════════════════════ */
@media(max-width:380px){
  .hero-h1 { font-size:1.75rem; }
  .nav-btn { display:none; }
  .tab { padding:11px 10px; font-size:.54rem; }
  .stat-num { font-size:1.5rem; }
  .app-main { padding:12px; }
  .chat-msgs { max-height:150px; }
}