/* style.css — Cipher Works: steampunk cipher academy */
:root{
  --bg:#0e0a06; --bg-2:#1a140e; --panel:#241c12; --panel-2:#2e2318; --panel-3:#382c1e;
  --border:#4a3820; --border-light:#6a5030; --border-bright:#8a6a3e;
  --brass:#c9a14a; --brass-bright:#f0d078; --brass-dark:#7a5e22;
  --copper:#b87333; --copper-bright:#e0985a; --copper-dark:#6a3e18;
  --text:#e8dcc8; --text-dim:#9a8870; --text-bright:#f8efda;
  --accent:#d4a843; --success:#8aaa5a; --success-bright:#a8c46e; --error:#d45a3a;
  --steam:rgba(220,200,170,0.05);
  --rivet:#7a5e22;
  --font-display:Georgia,'Times New Roman',serif;
  --font-body:Georgia,'Times New Roman',serif;
  --font-mono:ui-monospace,'SF Mono','Courier New',Consolas,monospace;
  --panel-grad:linear-gradient(165deg,var(--panel) 0%,var(--panel-2) 100%);
  --brass-grad:linear-gradient(180deg,var(--brass-bright) 0%,var(--brass) 50%,var(--brass-dark) 100%);
  --copper-grad:linear-gradient(180deg,var(--copper-bright) 0%,var(--copper) 50%,var(--copper-dark) 100%);
  --sh-sm:0 2px 6px rgba(0,0,0,0.4);
  --sh-md:0 4px 16px rgba(0,0,0,0.5);
  --sh-lg:0 10px 32px rgba(0,0,0,0.55);
  --sh-inset:inset 0 1px 0 rgba(255,220,180,0.07);
  color-scheme:dark;
}
@media (prefers-color-scheme:light){
  :root{
    --bg:#e8dcc0; --bg-2:#ddd0b0; --panel:#f0e4c8; --panel-2:#e6d8b4; --panel-3:#ddd0a8;
    --border:#a08030; --border-light:#8a6a20; --border-bright:#7a5a10;
    --brass:#8a6818; --brass-bright:#6a4e10; --brass-dark:#b89030;
    --copper:#7a4218; --copper-bright:#5a3210; --copper-dark:#a06828;
    --text:#2a1a08; --text-dim:#5a4828; --text-bright:#1a0a00;
    --steam:rgba(255,250,240,0.4);
    --rivet:#a08030;
    --panel-grad:linear-gradient(165deg,var(--panel) 0%,var(--panel-2) 100%);
    --brass-grad:linear-gradient(180deg,var(--brass-bright) 0%,var(--brass) 50%,var(--brass-dark) 100%);
    --copper-grad:linear-gradient(180deg,var(--copper-bright) 0%,var(--copper) 50%,var(--copper-dark) 100%);
    --sh-sm:0 2px 6px rgba(60,40,10,0.15);
    --sh-md:0 4px 16px rgba(60,40,10,0.2);
    --sh-lg:0 10px 32px rgba(60,40,10,0.22);
    --sh-inset:inset 0 1px 0 rgba(255,250,240,0.5);
    color-scheme:light;
  }
}
html[data-theme="dark"]{
  --bg:#0e0a06; --bg-2:#1a140e; --panel:#241c12; --panel-2:#2e2318; --panel-3:#382c1e;
  --border:#4a3820; --border-light:#6a5030; --border-bright:#8a6a3e;
  --brass:#c9a14a; --brass-bright:#f0d078; --brass-dark:#7a5e22;
  --copper:#b87333; --copper-bright:#e0985a; --copper-dark:#6a3e18;
  --text:#e8dcc8; --text-dim:#9a8870; --text-bright:#f8efda;
  --steam:rgba(220,200,170,0.05);
  --rivet:#7a5e22; color-scheme:dark;
}
html[data-theme="light"]{
  --bg:#e8dcc0; --bg-2:#ddd0b0; --panel:#f0e4c8; --panel-2:#e6d8b4; --panel-3:#ddd0a8;
  --border:#a08030; --border-light:#8a6a20; --border-bright:#7a5a10;
  --brass:#8a6818; --brass-bright:#6a4e10; --brass-dark:#b89030;
  --copper:#7a4218; --copper-bright:#5a3210; --copper-dark:#a06828;
  --text:#2a1a08; --text-dim:#5a4828; --text-bright:#1a0a00;
  --steam:rgba(255,250,240,0.4);
  --rivet:#a08030; color-scheme:light;
}

*{box-sizing:border-box;}
html,body{margin:0;padding:0;height:100%;overflow:hidden;}
body{
  font-family:var(--font-mono);
  background:var(--bg);color:var(--text);
  touch-action:manipulation;-webkit-tap-highlight-color:transparent;
  -webkit-font-smoothing:antialiased;
}
#app{
  display:flex;flex-direction:column;height:100vh;height:100dvh;
  position:relative;overflow:hidden;
  background:
    radial-gradient(ellipse at 20% 0%,rgba(184,115,51,0.08),transparent 50%),
    radial-gradient(ellipse at 80% 100%,rgba(201,161,74,0.06),transparent 50%),
    radial-gradient(ellipse at 50% 50%,rgba(0,0,0,0.12),transparent 70%),
    var(--bg);
}
html[data-theme="light"] #app{
  background:
    radial-gradient(ellipse at 20% 0%,rgba(184,115,51,0.12),transparent 50%),
    radial-gradient(ellipse at 80% 100%,rgba(201,161,74,0.1),transparent 50%),
    var(--bg);
}

/* Background gears */
.bg-gears{position:absolute;inset:0;pointer-events:none;z-index:0;overflow:hidden;}
.bg-gear{position:absolute;}
.steam-layer{
  position:absolute;inset:0;pointer-events:none;z-index:0;
  background:
    radial-gradient(ellipse 60% 40% at 50% -10%,var(--steam),transparent),
    radial-gradient(ellipse 40% 30% at 10% 50%,var(--steam),transparent),
    radial-gradient(ellipse 50% 35% at 90% 60%,var(--steam),transparent);
  animation:steam-drift 12s ease-in-out infinite alternate;
}
@keyframes steam-drift{0%{opacity:0.5;transform:translateY(0);}100%{opacity:0.8;transform:translateY(-10px);}}
@keyframes gear-spin{from{transform:rotate(0deg);}to{transform:rotate(360deg);}}

/* Pipe frame */
.pipe-frame{position:absolute;inset:0;pointer-events:none;z-index:0;}
.pipe{
  position:absolute;
  background:linear-gradient(180deg,var(--copper-dark),var(--copper),var(--copper-dark));
  box-shadow:inset 0 1px 0 rgba(255,220,180,0.2),inset 0 -1px 0 rgba(0,0,0,0.3),0 0 8px rgba(0,0,0,0.3);
}
.pipe-top{top:0;left:0;right:0;height:3px;}
.pipe-bottom{bottom:0;left:0;right:0;height:3px;}
.pipe-left{top:0;bottom:0;left:0;width:3px;background:linear-gradient(90deg,var(--copper-dark),var(--copper),var(--copper-dark));}
.pipe-right{top:0;bottom:0;right:0;width:3px;background:linear-gradient(90deg,var(--copper-dark),var(--copper),var(--copper-dark));}
.pipe-corner{
  position:absolute;width:14px;height:14px;
  background:radial-gradient(circle,var(--brass-bright),var(--brass),var(--brass-dark));
  border-radius:50%;box-shadow:0 0 6px rgba(0,0,0,0.4),inset 0 1px 1px rgba(255,240,200,0.3);
  border:1px solid var(--brass-dark);
}
.pipe-tl{top:-5px;left:-5px;}
.pipe-tr{top:-5px;right:-5px;}
.pipe-bl{bottom:-5px;left:-5px;}
.pipe-br{bottom:-5px;right:-5px;}

/* Steam wisps */
.steam-wisp{
  position:absolute;
  width:22px;height:22px;
  background:radial-gradient(circle,rgba(220,200,170,0.12),transparent 70%);
  border-radius:50%;
  filter:blur(7px);
  pointer-events:none;
  animation:steam-rise 4.5s ease-out infinite;
}
.sw-tl{top:-12px;left:8px;animation-delay:0s;}
.sw-tr{top:-12px;right:8px;animation-delay:1.4s;}
.sw-bl{bottom:-12px;left:8px;animation-delay:2.8s;}
.sw-br{bottom:-12px;right:8px;animation-delay:3.6s;}
@keyframes steam-rise{
  0%{opacity:0;transform:translateY(0) scale(0.4);}
  15%{opacity:0.5;}
  50%{opacity:0.25;transform:translateY(-35px) scale(1.1);}
  100%{opacity:0;transform:translateY(-70px) scale(1.8);}
}

/* Header */
.factory-header{
  display:flex;align-items:center;justify-content:space-between;
  padding:0.75rem 1.1rem;gap:0.5rem;
  background:linear-gradient(180deg,var(--panel),var(--panel-2));
  border-bottom:3px solid var(--border);
  box-shadow:var(--sh-md),inset 0 -1px 0 rgba(0,0,0,0.3);
  position:relative;z-index:10;
}
.factory-header::after{
  content:'';position:absolute;bottom:-3px;left:0;right:0;height:3px;
  background:linear-gradient(90deg,transparent 5%,var(--copper) 20%,var(--brass) 50%,var(--copper) 80%,transparent 95%);
}
.factory-header::before{
  content:'';position:absolute;top:4px;left:8px;width:5px;height:5px;
  background:radial-gradient(circle,var(--brass-bright),var(--rivet));
  border-radius:50%;box-shadow:0 1px 1px rgba(0,0,0,0.4);
}
.header-left{display:flex;align-items:center;gap:0.7rem;min-width:0;}
.logo-gear{flex-shrink:0;filter:drop-shadow(0 0 8px rgba(201,161,74,0.4));}
.factory-name{
  font-family:var(--font-display);font-weight:900;font-size:1.35rem;
  margin:0;color:var(--brass-bright);letter-spacing:0.08em;line-height:1;
  text-shadow:0 1px 3px rgba(0,0,0,0.5),0 0 12px rgba(201,161,74,0.15);
}
.factory-sub{
  margin:0.2rem 0 0;font-size:0.6rem;color:var(--text-dim);
  letter-spacing:0.1em;font-family:var(--font-body);font-style:italic;
}
.header-stats{display:flex;gap:0.5rem;flex-shrink:0;}
.stat-chip{
  display:flex;align-items:center;gap:0.3rem;
  background:var(--bg-2);border:1px solid var(--border);
  border-radius:20px;padding:0.3rem 0.7rem;
  font-family:var(--font-display);font-weight:700;font-size:0.85rem;color:var(--brass-bright);
  box-shadow:inset 0 1px 3px rgba(0,0,0,0.3),0 1px 2px rgba(0,0,0,0.2);
  transition:transform 0.2s ease,box-shadow 0.2s ease;
}
.stat-chip:hover{transform:translateY(-1px);box-shadow:inset 0 1px 3px rgba(0,0,0,0.3),0 3px 8px rgba(0,0,0,0.3);}
.chip-icon{width:16px;height:16px;color:var(--copper);}
.chip-label{font-size:0.5rem;letter-spacing:0.1em;color:var(--text-dim);font-family:var(--font-mono);}

/* View */
.view{
  flex:1;overflow-y:auto;overflow-x:hidden;
  padding:1.1rem;position:relative;z-index:1;
  -webkit-overflow-scrolling:touch;
  scroll-behavior:smooth;
}
.view::-webkit-scrollbar{width:10px;}
.view::-webkit-scrollbar-track{background:var(--bg-2);border-left:1px solid var(--border);}
.view::-webkit-scrollbar-thumb{
  background:var(--copper-grad);border-radius:5px;border:1px solid var(--copper-dark);
}
.view-enter{animation:view-enter 0.35s cubic-bezier(0.22,0.61,0.36,1);}
@keyframes view-enter{
  0%{opacity:0;transform:translateY(8px);}
  100%{opacity:1;transform:translateY(0);}
}

/* Bottom nav */
.bottom-nav{
  display:flex;background:linear-gradient(180deg,var(--panel-2),var(--panel));
  border-top:3px solid var(--border);padding:0.35rem;gap:0.35rem;
  position:relative;z-index:10;box-shadow:0 -4px 16px rgba(0,0,0,0.4),var(--sh-inset);
}
.bottom-nav::before{
  content:'';position:absolute;top:-3px;left:0;right:0;height:3px;
  background:linear-gradient(90deg,transparent 5%,var(--copper) 20%,var(--brass) 50%,var(--copper) 80%,transparent 95%);
}
.nav-btn{
  flex:1;display:flex;flex-direction:column;align-items:center;gap:0.2rem;
  background:transparent;border:1px solid transparent;border-radius:10px;
  padding:0.5rem 0.3rem;color:var(--text-dim);cursor:pointer;
  transition:all 0.2s ease;font-family:inherit;
}
.nav-btn:hover,.nav-btn:active{
  background:var(--bg-2);color:var(--brass-bright);
  border-color:var(--border);box-shadow:inset 0 1px 3px rgba(0,0,0,0.3);
}
.nav-icon{width:22px;height:22px;transition:transform 0.2s ease;}
.nav-btn:hover .nav-icon{transform:scale(1.1);}
.nav-label{font-size:0.6rem;letter-spacing:0.08em;text-transform:uppercase;font-family:var(--font-display);font-weight:700;}

/* Ornate divider */
.ornate-divider{
  display:flex;align-items:center;gap:0.8rem;margin:1.4rem 0;
}
.od-line{
  flex:1;height:2px;
  background:linear-gradient(90deg,transparent,var(--brass-dark),var(--brass),var(--brass-dark),transparent);
}

/* ═══ LOBBY ═══ */
.lobby{max-width:920px;margin:0 auto;}
.welcome-banner{
  display:flex;align-items:center;gap:1.1rem;
  background:var(--panel-grad);
  border:2px solid var(--border);border-radius:16px;
  padding:1.3rem;margin-bottom:0.5rem;position:relative;overflow:hidden;
  box-shadow:var(--sh-lg),var(--sh-inset);
}
.welcome-banner::before{
  content:'';position:absolute;top:0;left:0;right:0;height:3px;
  background:linear-gradient(90deg,var(--copper-dark),var(--copper),var(--brass),var(--copper),var(--copper-dark));
}
.welcome-banner::after{
  content:'';position:absolute;bottom:6px;right:8px;width:5px;height:5px;
  background:radial-gradient(circle,var(--brass-bright),var(--rivet));
  border-radius:50%;box-shadow:0 1px 1px rgba(0,0,0,0.4);
}
.banner-gear{flex-shrink:0;filter:drop-shadow(0 0 10px rgba(201,161,74,0.25));}
.welcome-title{font-family:var(--font-display);font-weight:900;font-size:1.55rem;color:var(--brass-bright);margin:0 0 0.35rem;letter-spacing:0.05em;text-shadow:0 1px 3px rgba(0,0,0,0.5);}
.welcome-msg{margin:0;font-size:0.85rem;line-height:1.65;color:var(--text-dim);font-family:var(--font-body);}
.welcome-msg strong{color:var(--brass);font-family:var(--font-display);}

.floor-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:0.9rem;}
.floor-card{
  background:var(--panel-grad);
  border:2px solid var(--border);border-radius:14px;overflow:hidden;
  cursor:pointer;transition:transform 0.25s cubic-bezier(0.22,0.61,0.36,1),box-shadow 0.25s ease,border-color 0.25s ease;
  position:relative;
  box-shadow:var(--sh-md),var(--sh-inset);
}
.floor-card:hover{transform:translateY(-5px);box-shadow:var(--sh-lg),0 0 16px rgba(201,161,74,0.12);border-color:var(--brass-dark);}
.floor-card:active{transform:translateY(-2px);}
.floor-card.locked{opacity:0.5;cursor:not-allowed;}
.floor-card.locked:hover{transform:none;box-shadow:var(--sh-md);border-color:var(--border);}
.floor-card-top{
  display:flex;align-items:center;justify-content:space-between;
  padding:0.85rem;border-bottom:2px solid var(--border);position:relative;
  background:rgba(0,0,0,0.15);
}
.floor-number{
  font-family:var(--font-display);font-weight:900;font-size:2rem;
  color:var(--brass);line-height:1;text-shadow:0 1px 2px rgba(0,0,0,0.5),0 0 8px rgba(201,161,74,0.2);
}
.floor-gear{filter:drop-shadow(0 0 6px rgba(201,161,74,0.2));}
.badge-stamp{position:absolute;top:0.4rem;right:0.4rem;width:30px;height:30px;display:flex;align-items:center;justify-content:center;}
.badge-check{
  position:absolute;font-size:0.7rem;color:var(--bg);font-weight:900;
  font-family:var(--font-display);
}
.floor-card-body{padding:0.85rem;}
.floor-label{font-size:0.58rem;letter-spacing:0.12em;color:var(--text-dim);margin:0 0 0.35rem;text-transform:uppercase;font-family:var(--font-display);font-weight:700;}
.floor-name{font-family:var(--font-display);font-weight:700;font-size:1.02rem;color:var(--text-bright);margin:0 0 0.25rem;letter-spacing:0.02em;}
.floor-era{font-size:0.7rem;color:var(--copper-bright);margin:0 0 0.55rem;font-family:var(--font-body);font-style:italic;}
.floor-status{font-size:0.7rem;color:var(--text-dim);margin:0;font-family:var(--font-mono);}
.floor-status.done{color:var(--success);}
.floor-lock{font-size:0.7rem;color:var(--error);margin:0;font-family:var(--font-mono);}

.achievement-banner{
  display:flex;align-items:center;gap:1rem;
  background:var(--panel-grad);
  border:2px solid var(--brass);border-radius:16px;
  padding:1.3rem;margin-top:1.4rem;
  box-shadow:var(--sh-lg),var(--sh-inset);
}
.achievement-banner.gold{border-color:var(--brass-bright);box-shadow:0 0 28px rgba(201,161,74,0.28),var(--sh-lg);}
.ach-gear{flex-shrink:0;}
.achievement-banner h3{font-family:var(--font-display);color:var(--brass-bright);margin:0 0 0.35rem;font-size:1.18rem;letter-spacing:0.04em;}
.achievement-banner p{margin:0;font-size:0.82rem;color:var(--text-dim);font-family:var(--font-body);line-height:1.55;}

/* ═══ LESSON ═══ */
.lesson{max-width:720px;margin:0 auto;}
.lesson-back{margin-bottom:0.9rem;}
.lesson-header{
  display:flex;align-items:center;gap:1.1rem;
  background:var(--panel-grad);
  border:2px solid var(--border);border-left:5px solid var(--accent,var(--brass));
  border-radius:14px;padding:1.3rem;margin-bottom:1.2rem;
  box-shadow:var(--sh-md),var(--sh-inset);
}
.lesson-header-gear{flex-shrink:0;filter:drop-shadow(0 0 10px rgba(201,161,74,0.2));}
.lesson-floor-label{font-size:0.58rem;letter-spacing:0.12em;color:var(--text-dim);margin:0;text-transform:uppercase;font-family:var(--font-display);font-weight:700;}
.lesson-title{font-family:var(--font-display);font-weight:900;font-size:1.6rem;color:var(--brass-bright);margin:0.25rem 0;letter-spacing:0.03em;text-shadow:0 1px 3px rgba(0,0,0,0.5);}
.lesson-era{font-size:0.75rem;color:var(--copper-bright);margin:0;font-family:var(--font-body);font-style:italic;}

.lesson-section{
  background:var(--panel);border:2px solid var(--border);border-radius:14px;
  padding:1.3rem;margin-bottom:0.9rem;position:relative;
  box-shadow:var(--sh-md),var(--sh-inset);
}
.lesson-section h3{
  display:flex;align-items:center;gap:0.6rem;
  font-family:var(--font-display);font-weight:700;font-size:1.18rem;
  color:var(--brass);margin:0 0 0.8rem;letter-spacing:0.03em;
}
.section-icon{flex-shrink:0;display:inline-block;}
.lesson-intro{font-size:0.95rem;line-height:1.7;color:var(--text-bright);margin:0;font-family:var(--font-body);}
.lesson-how{font-size:0.85rem;line-height:1.7;color:var(--text-dim);margin:0 0 1rem;font-family:var(--font-body);}

/* Demo diagrams */
.demo-diagram{margin-top:1.1rem;padding-top:1.1rem;border-top:1px dashed var(--border);}
.caesar-wheel-container{display:flex;flex-direction:column;align-items:center;gap:0.3rem;}
.caesar-wheel-svg{width:220px;height:220px;max-width:100%;filter:drop-shadow(0 4px 12px rgba(0,0,0,0.4));}
.diagram-caption{font-size:0.75rem;color:var(--text-dim);text-align:center;margin:0.6rem 0 0;font-style:italic;font-family:var(--font-body);line-height:1.5;}
.caesar-mapping{
  font-family:var(--font-display);font-weight:700;font-size:0.85rem;
  color:var(--brass-bright);text-align:center;margin:0.4rem 0 0;
  letter-spacing:0.05em;line-height:1.6;
}

.sub-table{display:flex;flex-direction:column;align-items:center;overflow-x:auto;padding:0.5rem 0;}
.sub-row{display:flex;gap:2px;}
.sub-cell{
  display:flex;align-items:center;justify-content:center;
  width:22px;height:26px;font-size:0.7rem;font-weight:700;
  font-family:var(--font-display);color:var(--brass-bright);
  background:var(--bg-2);border:1px solid var(--border);border-radius:3px;
  box-shadow:var(--sh-inset);
}
.sub-arrows{display:flex;gap:2px;color:var(--copper);font-size:0.6rem;}
.sub-arrow{width:22px;text-align:center;}

.vig-demo{overflow-x:auto;}
.vig-table{border-collapse:collapse;width:100%;min-width:300px;}
.vig-table td{text-align:center;padding:0.45rem 0.2rem;border:1px solid var(--border);font-family:var(--font-display);font-weight:700;}
.vig-label{font-size:0.58rem;color:var(--text-dim);background:var(--bg-2);text-transform:uppercase;letter-spacing:0.08em;}
.vig-key{color:var(--copper-bright);font-size:0.9rem;}
.vig-plain{color:var(--text-bright);font-size:0.9rem;}
.vig-shift{color:var(--text-dim);font-size:0.75rem;}
.vig-cipher{color:var(--brass-bright);font-size:1.1rem;text-shadow:0 0 8px rgba(201,161,74,0.2);}

.sym-demo{display:flex;gap:1.1rem;flex-wrap:wrap;align-items:flex-start;}
.sym-lock{display:flex;flex-direction:column;align-items:center;gap:0.3rem;flex-shrink:0;}
.lock-body{
  width:50px;height:40px;background:var(--copper-grad);border:2px solid var(--copper-dark);
  border-radius:6px;position:relative;box-shadow:inset 0 2px 4px rgba(0,0,0,0.3),0 2px 4px rgba(0,0,0,0.3);
}
.lock-keyhole{
  width:8px;height:14px;background:var(--bg);border-radius:4px 4px 0 0;
  position:absolute;top:8px;left:50%;transform:translateX(-50%);
}
.lock-keyhole::after{content:'';position:absolute;bottom:-4px;left:50%;transform:translateX(-50%);width:12px;height:6px;background:var(--bg);border-radius:50%;}
.sym-alpha-gen{flex:1;min-width:200px;}
.sym-step{font-size:0.8rem;color:var(--text-dim);margin:0.35rem 0;font-family:var(--font-body);}
.sym-key{color:var(--brass-bright);font-weight:700;font-family:var(--font-display);letter-spacing:0.1em;}
.sym-mono{font-family:var(--font-display);color:var(--copper-bright);letter-spacing:0.15em;font-weight:700;}
.sym-alpha-grid{display:flex;flex-wrap:wrap;gap:3px;margin-top:0.55rem;}
.sym-alpha-cell{
  display:flex;align-items:center;justify-content:center;
  width:24px;height:28px;font-size:0.75rem;font-weight:700;
  font-family:var(--font-display);color:var(--text-bright);
  background:var(--bg-2);border:1px solid var(--border);border-radius:3px;
  box-shadow:var(--sh-inset);
}
.sym-alpha-key{background:var(--copper-grad);color:var(--brass-bright);border-color:var(--copper-dark);text-shadow:0 1px 1px rgba(0,0,0,0.3);}

/* ROT13 demo */
.rot13-demo{display:flex;gap:1.1rem;flex-wrap:wrap;align-items:center;justify-content:center;}
.rot13-wheel .caesar-wheel-svg{width:160px;height:160px;}
.rot13-self-inverse{flex:1;min-width:180px;}
.rot13-step{font-size:0.85rem;color:var(--text-dim);margin:0.35rem 0;font-family:var(--font-body);}
.rot13-result{color:var(--brass-bright);font-weight:700;font-family:var(--font-display);letter-spacing:0.1em;}
.rot13-note{font-size:0.75rem;color:var(--copper-bright);margin:0.55rem 0 0;font-style:italic;font-family:var(--font-body);}

/* Rail Fence demo */
.railfence-demo{display:flex;flex-direction:column;gap:0.9rem;align-items:center;}
.rf-zigzag{display:flex;flex-direction:column;gap:0.3rem;overflow-x:auto;width:100%;}
.rf-rail{display:flex;align-items:center;gap:2px;}
.rf-rail-label{font-size:0.55rem;color:var(--text-dim);min-width:40px;font-family:var(--font-display);font-weight:700;text-transform:uppercase;letter-spacing:0.05em;}
.rf-letter{display:flex;align-items:center;justify-content:center;width:22px;height:26px;font-size:0.75rem;font-weight:700;font-family:var(--font-display);color:var(--brass-bright);background:var(--copper-grad);border:1px solid var(--copper-dark);border-radius:3px;text-shadow:0 1px 1px rgba(0,0,0,0.3);}
.rf-empty{display:flex;align-items:center;justify-content:center;width:22px;height:26px;font-size:0.6rem;color:var(--border);opacity:0.4;}
.rf-readoff{display:flex;flex-direction:column;gap:0.3rem;align-items:center;}
.rf-rail-text{font-size:0.75rem;color:var(--copper-bright);font-family:var(--font-mono);letter-spacing:0.1em;}

/* Affine demo */
.affine-demo{display:flex;flex-direction:column;gap:0.9rem;align-items:center;}
.affine-formula{font-family:var(--font-display);font-weight:900;font-size:1.3rem;color:var(--brass-bright);letter-spacing:0.05em;text-shadow:0 0 12px rgba(201,161,74,0.2);padding:0.55rem 1.1rem;background:var(--bg-2);border:2px solid var(--border);border-radius:8px;}
.affine-example{width:100%;overflow-x:auto;}
.affine-step{font-size:0.8rem;color:var(--text-dim);margin:0 0 0.55rem;font-family:var(--font-body);}
.affine-table td{text-align:center;padding:0.45rem 0.2rem;border:1px solid var(--border);font-family:var(--font-display);font-weight:700;}

/* Try panel */
.try-panel{
  background:var(--bg-2);border:2px solid var(--border);border-radius:10px;padding:1.1rem;
  box-shadow:inset 0 2px 8px rgba(0,0,0,0.3);
}
.try-row{display:flex;align-items:center;gap:0.7rem;margin-bottom:0.8rem;flex-wrap:wrap;}
.try-row label{font-size:0.7rem;color:var(--text-dim);min-width:70px;text-transform:uppercase;letter-spacing:0.08em;font-family:var(--font-display);font-weight:700;}
.try-row input[type="text"]{
  flex:1;min-width:120px;background:var(--panel);border:2px solid var(--border-light);
  border-radius:6px;padding:0.55rem 0.75rem;color:var(--text-bright);
  font-family:var(--font-mono);font-size:0.9rem;letter-spacing:0.05em;
  box-shadow:inset 0 2px 4px rgba(0,0,0,0.3);
  transition:border-color 0.2s ease;
}
.try-row input[type="text"]:focus{outline:none;border-color:var(--brass);}
.try-row input[type="number"]{
  flex:1;min-width:60px;max-width:100px;background:var(--panel);border:2px solid var(--border-light);
  border-radius:6px;padding:0.55rem 0.75rem;color:var(--text-bright);
  font-family:var(--font-mono);font-size:0.9rem;
  box-shadow:inset 0 2px 4px rgba(0,0,0,0.3);
}
.try-row input[type="number"]:focus{outline:none;border-color:var(--brass);}
.try-row input[type="range"]{
  flex:1;accent-color:var(--brass);min-width:100px;
}
.shift-val{
  font-family:var(--font-display);font-weight:900;font-size:1.3rem;color:var(--brass-bright);
  min-width:30px;text-align:center;text-shadow:0 0 8px rgba(201,161,74,0.2);
}
.try-output{
  font-family:var(--font-display);font-weight:900;font-size:1.5rem;
  color:var(--brass-bright);letter-spacing:0.12em;text-align:center;
  padding:0.85rem;background:var(--panel);border:2px solid var(--border);
  border-radius:10px;margin-top:0.55rem;
  text-shadow:0 0 12px rgba(201,161,74,0.25);
  box-shadow:inset 0 2px 8px rgba(0,0,0,0.3);
}
.try-note{font-size:0.7rem;color:var(--text-dim);margin:0.55rem 0 0;text-align:center;font-family:var(--font-body);font-style:italic;}
.try-wheel-mini{display:flex;justify-content:center;margin-top:0.9rem;}
.try-wheel-mini .caesar-wheel-svg{width:150px;height:150px;}

/* Puzzle */
.puzzle-section{border:2px solid var(--brass-dark);box-shadow:var(--sh-md),0 0 12px rgba(201,161,74,0.1);}
.puzzle-panel{display:flex;flex-direction:column;gap:0.75rem;}
.puzzle-instruction{font-size:0.85rem;color:var(--text-dim);margin:0;font-family:var(--font-body);}
.puzzle-cipher{
  font-family:var(--font-display);font-weight:900;font-size:1.75rem;
  color:var(--copper-bright);letter-spacing:0.15em;text-align:center;
  padding:1.1rem;background:var(--bg-2);border:2px solid var(--border);
  border-radius:10px;text-shadow:0 0 12px rgba(184,115,51,0.25);
  box-shadow:inset 0 2px 10px rgba(0,0,0,0.4);
  transition:color 0.3s ease,border-color 0.3s ease,box-shadow 0.3s ease;
}
.puzzle-cipher.solved-flash{
  animation:cipher-solved 1.1s cubic-bezier(0.34,1.56,0.64,1);
}
@keyframes cipher-solved{
  0%{transform:scale(1);color:var(--copper-bright);border-color:var(--border);box-shadow:inset 0 2px 10px rgba(0,0,0,0.4);}
  25%{transform:scale(1.1);color:var(--success);border-color:var(--success);box-shadow:0 0 32px rgba(122,154,90,0.6),inset 0 2px 8px rgba(0,0,0,0.3);text-shadow:0 0 20px rgba(122,154,90,0.7);}
  60%{transform:scale(1.04);color:var(--success);border-color:var(--success);box-shadow:0 0 20px rgba(122,154,90,0.45),inset 0 2px 8px rgba(0,0,0,0.3);text-shadow:0 0 16px rgba(122,154,90,0.55);}
  100%{transform:scale(1);color:var(--success);border-color:var(--success);box-shadow:0 0 14px rgba(122,154,90,0.35),inset 0 2px 10px rgba(0,0,0,0.4);text-shadow:0 0 10px rgba(122,154,90,0.4);}
}
.puzzle-hint{
  background:var(--bg-2);border:1px solid var(--border);border-radius:8px;
  padding:0.65rem 0.85rem;font-size:0.8rem;
  transition:border-color 0.2s ease;
}
.puzzle-hint[open]{border-color:var(--copper-dark);}
.puzzle-hint summary{cursor:pointer;color:var(--copper-bright);font-weight:700;font-family:var(--font-display);letter-spacing:0.03em;}
.puzzle-hint summary:hover{color:var(--copper-bright);}
.puzzle-hint p{margin:0.55rem 0 0;color:var(--text-dim);font-family:var(--font-body);line-height:1.55;}
.puzzle-input-row{display:flex;gap:0.5rem;flex-wrap:wrap;}
.puzzle-input{
  flex:1;min-width:150px;background:var(--panel);border:2px solid var(--border-light);
  border-radius:8px;padding:0.65rem 0.85rem;color:var(--text-bright);
  font-family:var(--font-mono);font-size:1rem;letter-spacing:0.05em;
  transition:border-color 0.2s ease,box-shadow 0.2s ease;
  box-shadow:inset 0 2px 4px rgba(0,0,0,0.3);
}
.puzzle-input:focus{outline:none;border-color:var(--brass);box-shadow:inset 0 2px 4px rgba(0,0,0,0.3),0 0 10px rgba(201,161,74,0.18);}
.puzzle-input.shake{animation:shake 0.4s ease;}
@keyframes shake{0%,100%{transform:translateX(0);}25%{transform:translateX(-6px);}75%{transform:translateX(6px);}}
.puzzle-feedback{min-height:1.5rem;}
.puzzle-solved{color:var(--success);font-weight:700;font-size:0.9rem;font-family:var(--font-display);}

/* Buttons */
.btn-brass{
  background:var(--brass-grad);
  color:var(--bg);border:2px solid var(--brass-dark);border-radius:8px;
  padding:0.55rem 1.25rem;font-family:var(--font-display);font-weight:700;font-size:0.8rem;
  letter-spacing:0.06em;cursor:pointer;transition:all 0.2s ease;
  box-shadow:var(--sh-sm),inset 0 1px 0 rgba(255,240,200,0.3),inset 0 -2px 4px rgba(0,0,0,0.2);
  text-transform:uppercase;
}
.btn-brass:hover{background:linear-gradient(180deg,var(--brass-bright),var(--brass));transform:translateY(-2px);box-shadow:var(--sh-md),inset 0 1px 0 rgba(255,240,200,0.4),0 0 10px rgba(201,161,74,0.22);}
.btn-brass:active{transform:translateY(0);box-shadow:0 1px 4px rgba(0,0,0,0.4),inset 0 1px 3px rgba(0,0,0,0.3);}
.btn-brass:disabled{opacity:0.4;cursor:not-allowed;transform:none;}
.btn-sm{padding:0.38rem 0.85rem;font-size:0.7rem;}
.btn-check{flex-shrink:0;}
.btn-next{background:var(--copper-grad);border-color:var(--copper-dark);}
.btn-next:hover{background:linear-gradient(180deg,var(--copper-bright),var(--copper));box-shadow:var(--sh-md),inset 0 1px 0 rgba(255,240,200,0.4),0 0 10px rgba(184,115,51,0.22);}

.lesson-nav{display:flex;justify-content:space-between;gap:0.5rem;margin-top:1.1rem;}

.feedback-success{
  color:var(--success);font-weight:700;font-size:0.9rem;
  padding:0.55rem 0.8rem;background:rgba(122,154,90,0.12);border-radius:8px;
  border:1px solid rgba(122,154,90,0.35);font-family:var(--font-display);
  animation:feedback-pop 0.35s ease;
}
.feedback-error{
  color:var(--error);font-weight:700;font-size:0.9rem;
  padding:0.55rem 0.8rem;background:rgba(196,90,58,0.12);border-radius:8px;
  border:1px solid rgba(196,90,58,0.35);font-family:var(--font-display);
  animation:feedback-pop 0.35s ease;
}
@keyframes feedback-pop{
  0%{opacity:0;transform:translateY(-4px) scale(0.96);}
  100%{opacity:1;transform:translateY(0) scale(1);}
}

/* ═══ BLUEPRINT ═══ */
.blueprint{max-width:920px;margin:0 auto;}
.bp-header{text-align:center;margin-bottom:1.3rem;}
.bp-gear{display:inline-block;margin-bottom:0.55rem;}
.bp-header h2{font-family:var(--font-display);font-weight:900;font-size:1.75rem;color:var(--brass-bright);margin:0 0 0.35rem;letter-spacing:0.05em;text-shadow:0 1px 3px rgba(0,0,0,0.5);}
.bp-sub{font-size:0.8rem;color:var(--text-dim);margin:0;font-family:var(--font-body);font-style:italic;}
.bp-empty{text-align:center;padding:3rem 1rem;color:var(--text-dim);font-family:var(--font-body);}
.bp-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:1rem;}
.bp-card{
  background:var(--panel-grad);
  border:2px solid var(--border);border-top:4px solid var(--accent,var(--brass));
  border-radius:14px;padding:1.1rem;position:relative;
  box-shadow:var(--sh-md),var(--sh-inset);
  transition:transform 0.25s ease,box-shadow 0.25s ease;
}
.bp-card:hover{transform:translateY(-3px);box-shadow:var(--sh-lg);}
.bp-card-header{display:flex;align-items:center;gap:0.75rem;margin-bottom:0.8rem;position:relative;}
.bp-card-gear{flex-shrink:0;}
.bp-card-header h3{font-family:var(--font-display);font-weight:700;font-size:1.02rem;color:var(--text-bright);margin:0;letter-spacing:0.02em;}
.bp-card-era{font-size:0.65rem;color:var(--copper-bright);margin:0.12rem 0 0;font-family:var(--font-body);font-style:italic;}
.bp-badge{position:absolute;top:-0.3rem;right:-0.3rem;}
.bp-summary{font-size:0.85rem;color:var(--text-bright);line-height:1.6;margin:0 0 0.8rem;font-family:var(--font-body);}
.bp-detail{font-size:0.75rem;color:var(--text-dim);line-height:1.6;margin:0 0 0.8rem;font-family:var(--font-body);}
.bp-detail strong{color:var(--brass);font-family:var(--font-display);}
.bp-mini-diagram{
  background:var(--bg-2);border:1px solid var(--border);border-radius:10px;
  padding:0.9rem;text-align:center;margin-bottom:0.8rem;
  box-shadow:inset 0 2px 8px rgba(0,0,0,0.3);
}
.bp-mini-wheel{display:flex;justify-content:center;}
.bp-wheel-svg{width:100px;height:100px;filter:drop-shadow(0 2px 6px rgba(0,0,0,0.3));}
.bp-mini-label{font-size:0.65rem;color:var(--text-dim);margin:0.55rem 0 0;font-style:italic;font-family:var(--font-body);}
.bp-mini-sub{display:flex;gap:0.5rem;justify-content:center;flex-wrap:wrap;}
.bp-sub-pair{font-family:var(--font-display);font-weight:700;font-size:0.8rem;color:var(--copper-bright);background:var(--panel);padding:0.25rem 0.55rem;border-radius:5px;border:1px solid var(--border);}
.bp-mini-vig{display:flex;align-items:center;gap:0.3rem;flex-wrap:wrap;justify-content:center;}
.bp-vig-k{font-family:var(--font-display);font-weight:900;color:var(--copper-bright);}
.bp-vig-arrow{color:var(--text-dim);}
.bp-vig-s{font-size:0.75rem;color:var(--brass);}
.bp-vig-sep{color:var(--border-light);}
.bp-mini-sym{display:flex;align-items:center;gap:0.75rem;justify-content:center;}
.bp-sym-key{font-family:var(--font-display);font-weight:900;color:var(--brass-bright);background:var(--copper-grad);padding:0.35rem 0.65rem;border-radius:5px;border:1px solid var(--copper-dark);text-shadow:0 1px 1px rgba(0,0,0,0.3);}
.bp-sym-arrow{font-size:1.2rem;color:var(--copper);}
.bp-sym-alpha{font-size:0.7rem;color:var(--text-dim);font-family:var(--font-body);}
.bp-actions{text-align:center;}

/* ═══ QUIZ ═══ */
.quiz-screen{max-width:620px;margin:0 auto;}
.quiz-header{text-align:center;margin-bottom:1.3rem;}
.quiz-gear{display:inline-block;margin-bottom:0.55rem;}
.quiz-header h2{font-family:var(--font-display);font-weight:900;font-size:1.65rem;color:var(--brass-bright);margin:0 0 0.35rem;letter-spacing:0.05em;text-shadow:0 1px 3px rgba(0,0,0,0.5);}
.quiz-sub{font-size:0.8rem;color:var(--text-dim);margin:0;font-family:var(--font-body);font-style:italic;}
.quiz-list{display:flex;flex-direction:column;gap:0.75rem;}
.quiz-card{
  display:flex;align-items:center;gap:0.85rem;
  background:var(--panel-grad);
  border:2px solid var(--border);border-radius:14px;padding:0.95rem;
  cursor:pointer;transition:all 0.25s cubic-bezier(0.22,0.61,0.36,1);position:relative;
  box-shadow:var(--sh-md),var(--sh-inset);
}
.quiz-card:hover{transform:translateX(6px);border-color:var(--brass);box-shadow:var(--sh-md),0 0 10px rgba(201,161,74,0.12);}
.quiz-card:active{transform:translateX(3px);}
.quiz-card.locked{opacity:0.5;cursor:not-allowed;}
.quiz-card.locked:hover{transform:none;}
.quiz-card.passed{border-color:var(--brass);}
.quiz-card-gear{flex-shrink:0;}
.quiz-card-body{flex:1;min-width:0;}
.quiz-card-floor{font-size:0.58rem;letter-spacing:0.12em;color:var(--text-dim);margin:0;text-transform:uppercase;font-family:var(--font-display);font-weight:700;}
.quiz-card-body h3{font-family:var(--font-display);font-weight:700;font-size:0.97rem;color:var(--text-bright);margin:0.22rem 0;letter-spacing:0.02em;}
.quiz-card-status{font-size:0.7rem;color:var(--text-dim);margin:0;font-family:var(--font-mono);}
.quiz-card-status.passed{color:var(--success);}
.quiz-badge-stamp{position:relative;width:34px;height:34px;display:flex;align-items:center;justify-content:center;flex-shrink:0;}

.quiz-master-banner{
  display:flex;align-items:center;gap:1.1rem;
  background:var(--panel-grad);
  border:2px solid var(--brass-bright);border-radius:16px;
  padding:1.3rem;margin-top:1.4rem;box-shadow:0 0 28px rgba(201,161,74,0.25),var(--sh-lg);
}
.master-gear{flex-shrink:0;}
.quiz-master-banner h3{font-family:var(--font-display);color:var(--brass-bright);margin:0 0 0.35rem;letter-spacing:0.04em;}
.quiz-master-banner p{margin:0;font-size:0.82rem;color:var(--text-dim);font-family:var(--font-body);line-height:1.55;}

/* Active quiz */
.quiz-active-header{display:flex;align-items:center;gap:0.75rem;margin-bottom:1.1rem;}
.quiz-progress-bar{flex:1;height:10px;background:var(--bg-2);border:1px solid var(--border);border-radius:5px;overflow:hidden;box-shadow:inset 0 2px 4px rgba(0,0,0,0.3);}
.quiz-progress-fill{height:100%;background:linear-gradient(90deg,var(--copper),var(--brass));transition:width 0.35s cubic-bezier(0.22,0.61,0.36,1);box-shadow:0 0 8px rgba(201,161,74,0.35);}
.quiz-progress-text{font-size:0.75rem;color:var(--text-dim);font-family:var(--font-display);white-space:nowrap;font-weight:700;}
.quiz-question-card{
  background:var(--panel-grad);
  border:2px solid var(--border);border-radius:16px;padding:1.6rem;text-align:center;
  box-shadow:var(--sh-lg),var(--sh-inset);
}
.quiz-card-gear-large{display:inline-block;margin-bottom:0.55rem;}
.quiz-floor-tag{font-size:0.62rem;letter-spacing:0.12em;color:var(--copper-bright);margin:0 0 0.8rem;text-transform:uppercase;font-family:var(--font-display);font-weight:700;}
.quiz-question{font-family:var(--font-display);font-weight:700;font-size:1.18rem;color:var(--text-bright);margin:0 0 1.3rem;line-height:1.5;letter-spacing:0.02em;}
.quiz-options{display:flex;flex-direction:column;gap:0.65rem;}
.quiz-option{
  background:var(--bg-2);border:2px solid var(--border-light);border-radius:10px;
  padding:0.85rem 1.1rem;font-family:var(--font-mono);font-size:0.9rem;
  color:var(--text-bright);cursor:pointer;transition:all 0.2s ease;text-align:left;
  box-shadow:var(--sh-inset);
}
.quiz-option:hover:not(:disabled){border-color:var(--brass);background:var(--panel-2);transform:translateX(6px);box-shadow:var(--sh-sm),var(--sh-inset);}
.quiz-option:active:not(:disabled){transform:translateX(3px);}
.quiz-option:disabled{cursor:default;}
.quiz-option.opt-correct{border-color:var(--success);background:rgba(122,154,90,0.18);color:var(--success-bright);box-shadow:0 0 10px rgba(122,154,90,0.25);}
.quiz-option.opt-wrong{border-color:var(--error);background:rgba(196,90,58,0.18);color:var(--error);box-shadow:0 0 10px rgba(196,90,58,0.25);}
.quiz-feedback{margin-top:0.9rem;min-height:1.5rem;}

/* Quiz result */
.quiz-result{text-align:center;padding:1.1rem;}
.result-gear{display:inline-block;margin-bottom:0.55rem;filter:drop-shadow(0 0 18px rgba(201,161,74,0.45));}
.result-title{font-family:var(--font-display);font-weight:900;font-size:1.65rem;color:var(--brass-bright);margin:0 0 0.35rem;letter-spacing:0.04em;text-shadow:0 1px 3px rgba(0,0,0,0.5);}
.result-score{font-size:1.28rem;color:var(--copper-bright);font-family:var(--font-display);font-weight:700;margin:0 0 1.1rem;}
.result-badge{position:relative;width:100px;height:100px;margin:0 auto 0.55rem;display:flex;align-items:center;justify-content:center;filter:drop-shadow(0 4px 12px rgba(0,0,0,0.4));}
.result-badge-inner{
  position:absolute;width:50px;height:50px;border-radius:50%;
  background:var(--brass-grad);display:flex;align-items:center;justify-content:center;
  border:2px solid var(--brass-dark);
  box-shadow:inset 0 1px 0 rgba(255,240,200,0.3);
}
.badge-check.big{font-size:1.5rem;color:var(--bg);position:static;font-family:var(--font-display);}
.result-badge-label{font-family:var(--font-display);font-weight:700;color:var(--brass);margin:0;font-size:0.8rem;text-transform:uppercase;letter-spacing:0.12em;}
.result-badge-name{font-family:var(--font-display);font-weight:700;color:var(--brass-bright);margin:0.25rem 0 1.1rem;font-size:1.02rem;letter-spacing:0.03em;}
.result-encourage{font-size:0.85rem;color:var(--text-dim);margin:0 0 1.1rem;font-family:var(--font-body);line-height:1.55;}
.result-actions{display:flex;gap:0.5rem;justify-content:center;flex-wrap:wrap;}

/* Responsive */
@media (max-width:480px){
  .factory-name{font-size:1.05rem;}
  .factory-sub{font-size:0.52rem;}
  .stat-chip{padding:0.25rem 0.5rem;font-size:0.75rem;}
  .chip-icon{width:14px;height:14px;}
  .chip-label{display:none;}
  .welcome-banner{padding:1rem;gap:0.8rem;}
  .welcome-title{font-size:1.2rem;}
  .welcome-msg{font-size:0.78rem;}
  .banner-gear svg{width:55px;height:55px;}
  .lesson-header{padding:1rem;gap:0.8rem;}
  .lesson-title{font-size:1.2rem;}
  .lesson-section{padding:1rem;}
  .floor-grid{grid-template-columns:1fr 1fr;gap:0.55rem;}
  .floor-card-body{padding:0.65rem;}
  .floor-name{font-size:0.85rem;}
  .caesar-wheel-svg{width:180px;height:180px;}
  .try-wheel-mini .caesar-wheel-svg{width:130px;height:130px;}
  .puzzle-cipher{font-size:1.3rem;}
  .try-output{font-size:1.1rem;}
  .quiz-question{font-size:0.97rem;}
  .quiz-option{padding:0.75rem;font-size:0.82rem;}
  .bp-grid{grid-template-columns:1fr;}
  .nav-label{font-size:0.55rem;}
  .rot13-wheel .caesar-wheel-svg{width:130px;height:130px;}
  .affine-formula{font-size:1rem;}
  .view{padding:0.85rem;}
}
@media (max-width:360px){
  .floor-grid{grid-template-columns:1fr;}
  .header-stats{flex-direction:column;gap:0.2rem;}
}