/* ===== Assembly page styles ===== */
.hero-compact{padding:36px 20px}
.hero-compact h1{font-size:2.2rem}
.hero-compact .tagline{font-size:1.05rem}

/* Progress bar */
.progress-wrap{background:#fff;padding:14px 0;border-bottom:1px solid #e0e6ec;position:sticky;top:60px;z-index:90}
.progress-bar{height:10px;background:#e0e6ec;border-radius:5px;overflow:hidden}
.progress-fill{height:100%;width:0%;background:linear-gradient(90deg,var(--clr-accent),var(--clr-accent2));transition:width .4s}
.progress-label{margin-top:6px;font-size:.85rem;color:var(--clr-muted);text-align:center}

/* Step container */
.build-main{padding:30px 20px 120px}
.build-step{display:none;background:var(--clr-card);border-radius:var(--radius);box-shadow:var(--shadow);padding:28px;animation:fadeIn .35s ease}
.build-step.active{display:block}
@keyframes fadeIn{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}

.step-header{display:flex;align-items:center;gap:14px;margin-bottom:8px;flex-wrap:wrap}
.step-badge{background:var(--clr-accent);color:#fff;padding:6px 14px;border-radius:20px;font-weight:700;font-size:.85rem}
.step-header h2{color:var(--clr-primary);font-size:1.5rem;margin:0}
.step-intro{color:var(--clr-text);margin-bottom:20px;font-size:1rem;line-height:1.55}
.step-intro strong{color:var(--clr-primary)}

.step-body{display:grid;grid-template-columns:1.3fr 1fr;gap:24px;align-items:start}
@media (max-width:780px){.step-body{grid-template-columns:1fr}}

/* Visual stage */
.step-visual{background:#f0f4f8;border-radius:10px;padding:20px;min-height:280px;display:flex;flex-direction:column;justify-content:center;align-items:center;gap:14px}
.action-hint{color:var(--clr-muted);font-style:italic;font-size:.9rem;text-align:center}

/* Checklist */
.step-checklist h3{color:var(--clr-primary);font-size:1rem;margin-bottom:10px}
.check-list{list-style:none;display:flex;flex-direction:column;gap:8px;padding:0;margin:0}
.check-list li,.check-list label{display:flex;align-items:center;gap:10px;cursor:pointer;font-size:.95rem;padding:8px 12px;background:#f0f4f8;border-radius:8px;transition:background .15s}
.check-list label:hover{background:#e0eaf3}
.check-list input[type="checkbox"]{width:18px;height:18px;cursor:pointer;accent-color:var(--clr-accent)}
.check-list input[type="checkbox"]:disabled{cursor:not-allowed;opacity:.5}
.check-list input[type="checkbox"]:checked + *,
.check-list label:has(input:checked){background:#d4edda;color:#155724}

.info-list{list-style:disc inside;margin-bottom:14px;color:var(--clr-text);font-size:.92rem;line-height:1.7}

.warn-box{background:#fff3cd;border-left:4px solid #ffc107;padding:10px 14px;border-radius:6px;margin-top:12px;font-size:.9rem}
.warn-box.danger{background:#f8d7da;border-color:#dc3545;color:#721c24}

/* ===== STEP 1: Parts tray ===== */
.parts-tray{display:grid;grid-template-columns:repeat(auto-fill,minmax(120px,1fr));gap:12px;width:100%}
.part{background:#fff;border:2px solid #e0e6ec;border-radius:8px;padding:12px 8px;text-align:center;font-size:.78rem;transition:all .2s}
.part.checked{border-color:#28a745;background:#d4edda}
.part-icon{font-size:1.8rem;margin-bottom:4px}
.part-name{font-weight:600;color:var(--clr-primary);margin-bottom:2px}
.part-note{color:var(--clr-muted);font-size:.72rem;line-height:1.3}

/* ===== STEP 2: Slot stage ===== */
.stage-box{position:relative;width:100%;min-height:300px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:20px}

.motorboard{background:#0d6e3f;border-radius:8px;padding:16px;width:280px;color:#fff;position:relative;box-shadow:inset 0 0 0 2px #064a28}
.mb-label{font-size:.78rem;text-align:center;margin-bottom:8px;letter-spacing:.6px;text-transform:uppercase}
.mb-slot{height:60px;background:#064a28;border:2px dashed #fff;border-radius:6px;display:flex;align-items:center;justify-content:center;color:#caf0f8;font-size:.85rem;transition:all .2s}
.mb-slot.drag-over{background:#0a7a44;border-style:solid}
.mb-slot.filled{background:#0a7a44;border-style:solid}
.mb-slot.filled .slot-hint{display:none}
.mb-slot.filled::after{content:'micro:bit installed ✓';font-size:.85rem}
.mb-terminals{display:flex;gap:8px;margin-top:10px}
.terminal{background:#222;color:#ffe066;padding:4px 8px;border-radius:4px;font-size:.7rem;font-weight:700;flex:1;text-align:center}

.microbit-piece{background:#1a1a1a;border-radius:8px;padding:8px;width:140px;cursor:grab;user-select:none;transition:transform .15s}
.microbit-piece.big{width:180px;cursor:default}
.microbit-piece:active{cursor:grabbing;transform:scale(1.05)}
.microbit-piece.placed{opacity:.4;cursor:default;transform:none}
.microbit-piece.dragging{outline:3px solid var(--clr-accent2);outline-offset:3px}
.mb-face{background:#000;border-radius:6px;padding:10px;position:relative}
.mb-leds{display:grid;grid-template-columns:repeat(5,1fr);gap:4px;margin-bottom:8px}
.mb-leds span{width:8px;height:8px;background:#330;border-radius:1px;justify-self:center}
.mb-buttons{display:flex;justify-content:space-between;padding:0 6px}
.mb-btn{background:#888;color:#000;font-weight:700;font-size:.7rem;padding:3px 8px;border-radius:50%;width:22px;height:22px;display:inline-flex;align-items:center;justify-content:center}
.mb-edge{background:#d4af37;height:8px;margin-top:6px;border-radius:0 0 4px 4px;font-size:.55rem;color:#000;text-align:center;line-height:8px;text-transform:uppercase}

/* ===== STEPS 3 & 4: Wiring ===== */
.stage-wire{flex-direction:row;flex-wrap:wrap;justify-content:space-around}
.motor-pic{display:flex;flex-direction:column;align-items:center;gap:6px;min-width:120px}
.motor-body{background:#ffd60a;color:#000;font-weight:700;padding:14px 18px;border-radius:8px;border:2px solid #b8860b;font-size:.85rem}
.motor-wire{width:90px;height:28px;border-radius:14px;cursor:grab;position:relative;display:flex;align-items:center;justify-content:center;color:#fff;font-size:.72rem;font-weight:700;user-select:none;border:2px solid rgba(0,0,0,.2);box-shadow:0 2px 4px rgba(0,0,0,.15)}
.motor-wire::after{content:attr(data-wire);position:absolute;bottom:-16px;left:50%;transform:translateX(-50%);font-size:.65rem;color:var(--clr-muted);white-space:nowrap}
.motor-wire::before{content:'click me';font-size:.7rem}
.motor-wire.wire-a{background:#d62828}
.motor-wire.wire-b{background:#212529}
.motor-wire.placed{opacity:.4;cursor:default}
.motor-wire.dragging{outline:3px solid var(--clr-accent2);outline-offset:2px}

.terminal-block{background:#222;color:#fff;border-radius:8px;padding:14px;display:flex;flex-direction:column;align-items:center;gap:8px;min-width:120px}
.terminal-block.big{padding:18px;min-width:160px}
.terminal-label{font-size:.8rem;font-weight:700;letter-spacing:.6px;color:#ffe066}
.terminal-port{width:100px;height:44px;background:#444;border:3px dashed #aaa;border-radius:6px;display:flex;align-items:center;justify-content:center;color:#fff;font-weight:700;font-size:.85rem;transition:all .2s;cursor:pointer}
.terminal-port:hover{border-color:#fff;background:#555}
.terminal-port.drag-over{border-color:#fff;background:#666;transform:scale(1.05)}
.terminal-port.filled{background:#28a745;border-style:solid;border-color:#1e7e34;cursor:default}
.terminal-port.filled span{display:none}
.terminal-port.filled::after{content:'✓ wired';font-size:.78rem}

/* ===== STEP 5: Chassis ===== */
.stage-chassis{flex-direction:column}
.chassis-outline{background:#fff;border:3px dashed #6c757d;border-radius:14px;padding:30px;width:280px;height:240px;position:relative;display:flex;flex-direction:column;justify-content:space-between;align-items:center}
.chassis-label{position:absolute;top:6px;left:50%;transform:translateX(-50%);font-size:.7rem;color:var(--clr-muted);text-transform:uppercase;letter-spacing:.6px}
.chassis-center{font-size:.8rem;color:var(--clr-primary);font-weight:600;background:#e0eaf3;padding:6px 10px;border-radius:6px;text-align:center}
.drop-zone{width:50px;height:50px;border:2px dashed #6c757d;border-radius:50%;display:flex;align-items:center;justify-content:center;background:#f0f4f8;color:#6c757d;font-weight:700;transition:all .2s}
.drop-zone.drag-over{border-style:solid;background:#caf0f8}
.drop-zone.filled{background:#28a745;border-color:#28a745;color:#fff;border-style:solid}
.wheel-slot{position:absolute;bottom:30px}
.wheel-slot.wheel-left{left:-8px}
.wheel-slot.wheel-right{right:-8px}
.caster-slot{position:absolute;top:30px;width:38px;height:38px}

.parts-bench{display:flex;gap:14px;justify-content:center;background:#fff;padding:14px;border-radius:8px;border:1px solid #e0e6ec}
.bench-piece{font-size:1.8rem;cursor:grab;padding:8px 14px;background:#f0f4f8;border:2px solid #cbd5e0;border-radius:8px;user-select:none;transition:transform .15s}
.bench-piece:active{cursor:grabbing;transform:scale(1.1)}
.bench-piece.placed{opacity:.3;cursor:default}
.bench-piece.dragging{outline:3px solid var(--clr-accent2);outline-offset:2px;background:#fff}

/* ===== STEP 6: Battery ===== */
.battery-pack{background:#444;color:#fff;border-radius:8px;padding:14px;display:flex;flex-direction:column;align-items:center;gap:6px;min-width:130px}
.battery-pack.small{min-width:110px}
.bp-body{background:#666;padding:6px 10px;border-radius:4px;font-weight:700;font-size:.85rem;letter-spacing:.4px}
.bp-wire{min-width:90px;height:28px;border-radius:14px;cursor:grab;position:relative;display:flex;align-items:center;justify-content:center;color:#fff;font-size:.75rem;font-weight:700;padding:0 10px;user-select:none;border:2px solid rgba(255,255,255,.3);box-shadow:0 2px 4px rgba(0,0,0,.2)}
.bp-wire.bp-red{background:#d62828}
.bp-wire.bp-black{background:#000}
.bp-wire.bp-jst{background:#fff;color:#000;border-color:#888}
.bp-wire.placed{opacity:.4;cursor:default}
.bp-wire.dragging{outline:3px solid var(--clr-accent2);outline-offset:2px}

/* ===== STEP 7: Remote / JST ===== */
.jst-socket{margin-top:8px;background:#fff;border:2px dashed #888;height:22px;border-radius:3px;display:flex;align-items:center;justify-content:center;color:#888;font-size:.7rem;font-weight:700;transition:all .2s}
.jst-socket.drag-over{border-style:solid;border-color:var(--clr-accent);background:#caf0f8}
.jst-socket.filled{background:#28a745;color:#fff;border-color:#28a745;border-style:solid}
.jst-socket.filled span{display:none}
.jst-socket.filled::after{content:'✓ powered'}

/* ===== STEP 8: Design ===== */
.design-body{display:block}
.design-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:16px;margin-bottom:24px}
.design-event{padding:18px;border-radius:10px;color:#fff}
.design-event h3{margin-bottom:8px;font-size:1.05rem}
.design-event ul{list-style:disc inside;font-size:.88rem;line-height:1.6}
.design-event p{font-size:.85rem;margin-bottom:6px;opacity:.9}
.design-speed{background:linear-gradient(135deg,var(--evt-speed),#0077b6)}
.design-maneuver{background:linear-gradient(135deg,var(--evt-maneuver),#d35400)}
.design-sumo{background:linear-gradient(135deg,var(--evt-sumo),#9d0208)}

.design-decision h3{color:var(--clr-primary);margin-bottom:8px;font-size:1.1rem}
.design-decision > p{color:var(--clr-text);margin-bottom:14px;font-size:.95rem}
.design-options{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:12px;margin-bottom:20px}
.design-opt input{display:none}
.design-opt .opt-card{background:#fff;border:2px solid #e0e6ec;border-radius:8px;padding:14px;cursor:pointer;transition:all .15s;display:block}
.design-opt .opt-card strong{display:block;color:var(--clr-primary);margin-bottom:4px;font-size:.95rem}
.design-opt .opt-card span{font-size:.82rem;color:var(--clr-muted)}
.design-opt input:checked + .opt-card{border-color:var(--clr-accent);background:#e0f7fa;box-shadow:0 0 0 3px rgba(0,180,216,.15)}
.design-opt .opt-card:hover{border-color:var(--clr-accent)}

.sketch-area textarea{width:100%;padding:12px;border:2px solid #e0e6ec;border-radius:8px;font-family:inherit;font-size:.95rem;resize:vertical}
.sketch-area textarea:focus{outline:none;border-color:var(--clr-accent)}

.finish-banner{display:none;margin-top:24px;padding:24px;background:linear-gradient(135deg,#28a745,#218838);color:#fff;border-radius:10px;text-align:center;animation:fadeIn .5s}
.finish-banner.show{display:block}
.finish-banner h2{color:#fff;margin-bottom:6px}
.finish-banner a{color:#fff;text-decoration:underline;font-weight:700}

/* ===== Step nav ===== */
.step-nav-wrap{position:fixed;bottom:0;left:0;right:0;background:#fff;border-top:1px solid #e0e6ec;padding:12px 0;box-shadow:0 -2px 10px rgba(0,0,0,.05);z-index:50}
.step-nav{display:flex;align-items:center;justify-content:space-between;gap:14px}
.nav-btn{background:#e0e6ec;color:var(--clr-primary);border:none;padding:10px 22px;border-radius:8px;font-weight:600;cursor:pointer;font-size:.95rem;transition:all .15s;font-family:inherit}
.nav-btn:hover:not(:disabled){background:#caf0f8}
.nav-btn:disabled{opacity:.4;cursor:not-allowed}
.nav-btn.primary{background:var(--clr-accent);color:#fff}
.nav-btn.primary:hover:not(:disabled){background:#0077b6}
.nav-btn.primary:disabled{background:#a0c4d8;color:#fff}

.step-dots{display:flex;gap:6px}
.step-dot{width:12px;height:12px;border-radius:50%;background:#e0e6ec;transition:all .2s;cursor:pointer}
.step-dot.active{background:var(--clr-accent);transform:scale(1.3)}
.step-dot.done{background:#28a745}

@media (max-width:600px){
  .step-header h2{font-size:1.2rem}
  .nav-btn{padding:8px 14px;font-size:.85rem}
  .step-dot{width:10px;height:10px}
  .progress-wrap{top:auto;position:static}
}