/**
 * ============================================================================
 *  GPS IoT Tracking System — Mobile-First Design System
 * ============================================================================
 *
 *  ARCHITECTURE:
 *  - Mobile-first: base styles for phones, @media for larger screens
 *  - Bottom nav on mobile (app-like), top nav on desktop
 *  - Touch-friendly: min 44px tap targets, generous padding
 *  - CSS custom properties for easy theming & extension
 *  - Utility classes for common patterns
 *
 * ============================================================================
 */

/* ═══════════════════ Design Tokens ═══════════════════ */
:root {
    --bg-primary:    hsl(225, 25%, 8%);
    --bg-secondary:  hsl(225, 20%, 12%);
    --surface-1:     hsl(225, 20%, 15%);
    --surface-2:     hsl(225, 15%, 22%);
    --surface-3:     hsl(225, 15%, 28%);
    --text-primary:   hsl(210, 20%, 92%);
    --text-secondary: hsl(215, 15%, 60%);
    --text-tertiary:  hsl(215, 10%, 45%);
    --accent:        hsl(240, 80%, 65%);
    --accent-light:  hsl(240, 80%, 75%);
    --accent-glow:   hsla(240, 80%, 65%, 0.3);
    --success:       hsl(145, 65%, 42%);
    --warning:       hsl(45, 85%, 55%);
    --danger:        hsl(0, 72%, 55%);
    --info:          hsl(200, 80%, 55%);

    --space-xs:  0.25rem;
    --space-sm:  0.5rem;
    --space-md:  1rem;
    --space-lg:  1.5rem;
    --space-xl:  2rem;
    --space-2xl: 3rem;

    --radius-sm: 0.375rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;

    --shadow-sm:  0 1px 3px hsla(0,0%,0%,0.3);
    --shadow-md:  0 4px 12px hsla(0,0%,0%,0.4);
    --shadow-lg:  0 8px 32px hsla(0,0%,0%,0.5);
    --shadow-glow: 0 0 20px var(--accent-glow);

    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 400ms ease;

    /* Mobile bottom nav height — used to add padding to body */
    --bottom-nav-height: 60px;
    --top-bar-height: 56px;
}

/* ═══════════════════ Reset ═══════════════════ */
*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; -webkit-font-smoothing:antialiased; -webkit-tap-highlight-color:transparent; }
body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    /* Space for bottom nav on mobile */
    padding-bottom: calc(var(--bottom-nav-height) + env(safe-area-inset-bottom, 0px));
}

/* ═══════════════════ TOP BAR ═══════════════════ */
.top-bar {
    position: sticky;
    top: 0;
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-sm) var(--space-md);
    height: var(--top-bar-height);
    background: hsla(225, 25%, 10%, 0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--surface-2);
    transition: transform var(--transition-normal);
}
.top-bar--hidden { transform: translateY(-100%); }

.top-bar__brand { display:flex; align-items:center; gap:var(--space-sm); min-width:0; }
.top-bar__back {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.8rem;
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    white-space: nowrap;
    min-height: 36px;
    display: flex;
    align-items: center;
}
.top-bar__back:hover { color:var(--text-primary); background:var(--surface-2); }
.top-bar__icon { font-size:1.25rem; flex-shrink:0; }
.top-bar__title {
    font-size: 1rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--accent-light), var(--info));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.top-bar__device-id {
    font-family: var(--font-mono);
    font-size: 0.65rem;
    color: var(--text-tertiary);
    padding: 2px var(--space-xs);
    background: var(--surface-1);
    border-radius: var(--radius-sm);
    display: none; /* Show on desktop */
}
.top-bar__meta { display:flex; align-items:center; gap:var(--space-sm); }
.top-bar__badge {
    font-size: 0.65rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 3px var(--space-sm);
    background: var(--accent);
    color: white;
    border-radius: var(--radius-sm);
    white-space: nowrap;
}
.top-bar__clock { font-family:var(--font-mono); font-size:0.75rem; color:var(--text-secondary); display:none; }
.top-bar__refresh { font-size:0.65rem; color:var(--text-tertiary); display:none; }


/* ═══════════════════ BOTTOM NAV (Mobile App Pattern) ═══════════════════ */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    display: flex;
    justify-content: space-around;
    align-items: center;
    height: var(--bottom-nav-height);
    background: hsla(225, 25%, 10%, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-top: 1px solid var(--surface-2);
    padding-bottom: env(safe-area-inset-bottom, 0px);
}
@media (min-width: 768px) {
    .bottom-nav {
        top: 0; bottom: auto; height: 60px;
        background: var(--bg-secondary);
        border-top: none; border-bottom: 1px solid var(--surface-2);
        justify-content: flex-end; padding-right: var(--space-xl);
        padding-bottom: 0;
    }
}
.bottom-nav__item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2px;
    text-decoration: none;
    color: var(--text-tertiary);
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    min-width: 64px;
    min-height: 44px; /* iOS touch target */
    -webkit-tap-highlight-color: transparent;
}
.bottom-nav__item:active { transform:scale(0.92); }
.bottom-nav__item--active { color:var(--accent-light); }
.bottom-nav__item--active .bottom-nav__icon { transform:scale(1.15); }
.bottom-nav__icon { font-size:1.25rem; transition:transform var(--transition-fast); }
.bottom-nav__label { font-size:0.6rem; font-weight:500; letter-spacing:0.02em; }


/* ═══════════════════ CONTAINER ═══════════════════ */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--space-md);
    padding-top: var(--space-md);
}


/* ═══════════════════ SECTION TITLES ═══════════════════ */
.section-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-md);
}


/* ═══════════════════ MAPS ═══════════════════ */
.map-section { margin-bottom: var(--space-xl); }
.overview-map { height: 250px; border-radius: var(--radius-lg); border:1px solid var(--surface-2); overflow:hidden; }
.device-map   { height: 300px; border-radius: var(--radius-md); overflow:hidden; }


/* ═══════════════════ DEVICE CARDS ═══════════════════ */
.devices-section { margin-bottom: var(--space-xl); }
.device-grid {
    display: grid;
    grid-template-columns: 1fr; /* 1 column on mobile */
    gap: var(--space-md);
}
.device-card {
    display: block;
    text-decoration: none;
    color: inherit;
    background: var(--surface-1);
    border: 1px solid var(--surface-2);
    border-radius: var(--radius-lg);
    padding: var(--space-md);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
    -webkit-tap-highlight-color: transparent;
}
.device-card::before {
    content:''; position:absolute; top:0; left:0; right:0; height:3px;
    background:linear-gradient(90deg, var(--accent), var(--info));
    opacity:0; transition:opacity var(--transition-normal);
}
.device-card:hover { border-color:var(--accent); box-shadow:var(--shadow-glow); }
.device-card:hover::before { opacity:1; }
.device-card:active { transform:scale(0.98); }

.device-card__header { display:flex; justify-content:space-between; align-items:center; margin-bottom:var(--space-xs); }
.device-card__status {
    font-size:0.65rem; font-weight:600; text-transform:uppercase;
    letter-spacing:0.08em; padding:2px var(--space-sm); border-radius:9999px;
}
.status--online  { background:hsla(145,65%,42%,0.15); color:var(--success); }
.status--offline { background:hsla(0,72%,55%,0.1); color:var(--danger); }
.device-card__type { font-size:0.65rem; color:var(--text-tertiary); text-transform:uppercase; }
.device-card__name { font-size:1rem; font-weight:600; margin-bottom:2px; }
.device-card__id { font-family:var(--font-mono); font-size:0.7rem; color:var(--text-tertiary); margin-bottom:var(--space-sm); }

.device-card__stats { display:grid; grid-template-columns:1fr 1fr; gap:var(--space-sm); }
.stat { display:flex; flex-direction:column; gap:2px; }
.stat__label { font-size:0.65rem; color:var(--text-tertiary); }
.stat__value { font-size:0.8rem; font-weight:500; font-family:var(--font-mono); }
.stat__value--danger { color:var(--danger); }

.fuel-bar { margin-top:var(--space-sm); height:6px; background:var(--surface-2); border-radius:9999px; overflow:hidden; }
.fuel-bar__fill { height:100%; border-radius:9999px; background:linear-gradient(90deg,var(--danger),var(--warning),var(--success)); transition:width var(--transition-slow); }


/* ═══════════════════ STATS ROW ═══════════════════ */
.stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr); /* 3 cols on mobile */
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}
.stat-card {
    background: var(--surface-1);
    border: 1px solid var(--surface-2);
    border-radius: var(--radius-md);
    padding: var(--space-sm);
    text-align: center;
    transition: border-color var(--transition-fast);
}
.stat-card:hover { border-color:var(--surface-3); }
.stat-card__icon { font-size:1.25rem; margin-bottom:2px; }
.stat-card__label { font-size:0.55rem; color:var(--text-tertiary); text-transform:uppercase; letter-spacing:0.06em; }
.stat-card__value { font-size:0.8rem; font-weight:600; font-family:var(--font-mono); }


/* ═══════════════════ MAP + GAUGE ROW ═══════════════════ */
.map-gauge-row {
    display: grid;
    grid-template-columns: 1fr; /* Stack on mobile */
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}
.map-panel, .gauge-panel {
    background: var(--surface-1);
    border: 1px solid var(--surface-2);
    border-radius: var(--radius-lg);
    padding: var(--space-md);
}

/* Gauge */
.gauge-container { display:flex; justify-content:center; align-items:center; padding:var(--space-sm) 0; }
.gauge-svg { width:100%; max-width:220px; }
.gauge-arc { stroke:var(--success); transition:stroke-dasharray 1s ease, stroke 0.5s ease; }
.gauge-text { font-family:var(--font-mono); font-size:2rem; font-weight:700; fill:var(--text-primary); }
.gauge-label { font-family:var(--font-sans); font-size:0.75rem; fill:var(--text-tertiary); text-transform:uppercase; letter-spacing:0.1em; }
.gauge-detail { text-align:center; font-size:0.8rem; color:var(--text-secondary); margin-top:var(--space-xs); }


/* ═══════════════════ DATA TABLE ═══════════════════ */
.history-section { margin-bottom:var(--space-xl); }
.table-wrapper { overflow-x:auto; -webkit-overflow-scrolling:touch; border-radius:var(--radius-lg); border:1px solid var(--surface-2); }
.data-table { width:100%; border-collapse:collapse; font-size:0.7rem; font-family:var(--font-mono); }
.data-table thead { background:var(--surface-1); position:sticky; top:0; }
.data-table th {
    padding:var(--space-sm) var(--space-sm);
    text-align:left; font-weight:600; color:var(--text-secondary);
    text-transform:uppercase; letter-spacing:0.05em; font-size:0.6rem;
    border-bottom:2px solid var(--surface-2); white-space:nowrap;
}
.data-table td { padding:var(--space-sm); border-bottom:1px solid var(--surface-2); white-space:nowrap; }
.data-table tbody tr:hover { background:hsla(240,80%,65%,0.05); }
.data-table .danger { color:var(--danger); font-weight:600; }


/* ═══════════════════ API CARDS ═══════════════════ */
.api-section { margin-bottom:var(--space-xl); }
.api-grid { display:grid; grid-template-columns:1fr; gap:var(--space-md); }
.api-card {
    background:var(--surface-1); border:1px solid var(--surface-2);
    border-radius:var(--radius-md); padding:var(--space-md);
}
.api-card h4 { font-size:0.9rem; font-weight:600; margin-bottom:var(--space-sm); color:var(--accent-light); }
.api-card code { display:block; font-family:var(--font-mono); font-size:0.75rem; color:var(--info); margin-bottom:var(--space-sm); }
.api-card p { font-size:0.8rem; color:var(--text-secondary); }


/* ═══════════════════ CODE BLOCKS ═══════════════════ */
.code-block {
    background:var(--bg-primary); border:1px solid var(--surface-2);
    border-radius:var(--radius-md); padding:var(--space-md);
    overflow-x:auto; -webkit-overflow-scrolling:touch;
}
.code-block code { font-family:var(--font-mono); font-size:0.7rem; color:var(--success); white-space:pre; line-height:1.7; }


/* ═══════════════════ EMPTY STATE ═══════════════════ */
.empty-state {
    text-align:center; padding:var(--space-xl); background:var(--surface-1);
    border:2px dashed var(--surface-2); border-radius:var(--radius-xl);
}
.empty-state__icon { font-size:2.5rem; margin-bottom:var(--space-sm); }
.empty-state h3 { font-size:1.1rem; margin-bottom:var(--space-xs); }
.empty-state p { color:var(--text-secondary); margin-bottom:var(--space-md); font-size:0.85rem; }


/* ═══════════════════ INFO PAGE STYLES ═══════════════════ */
.info-page { max-width:900px; margin:0 auto; }
.info-card {
    background:var(--surface-1); border:1px solid var(--surface-2);
    border-radius:var(--radius-lg); padding:var(--space-lg); margin-bottom:var(--space-md);
}
.info-card h3 { font-size:0.95rem; font-weight:600; margin-bottom:var(--space-sm); color:var(--accent-light); }
.info-card p, .info-card li { font-size:0.85rem; color:var(--text-secondary); line-height:1.7; }
.info-card ul, .info-card ol { padding-left:var(--space-lg); }
.info-card li { margin-bottom:var(--space-xs); }
.info-card a { color:var(--accent-light); text-decoration:none; }
.info-card a:hover { text-decoration:underline; }

.info-hero {
    text-align:center; padding:var(--space-xl) var(--space-md);
    background:linear-gradient(135deg, hsla(240,80%,65%,0.1), hsla(200,80%,55%,0.1));
    border-radius:var(--radius-xl); border:1px solid var(--surface-2);
    margin-bottom:var(--space-xl);
}
.info-hero__icon { font-size:3rem; margin-bottom:var(--space-sm); }
.info-hero h2 { font-size:1.5rem; font-weight:700; margin-bottom:var(--space-xs); }
.info-hero p { color:var(--text-secondary); font-size:0.9rem; }

/* Improvement list */
.improvement-grid { display:grid; grid-template-columns:1fr; gap:var(--space-sm); }
.improvement-item {
    display:flex; gap:var(--space-sm); align-items:flex-start;
    padding:var(--space-sm) var(--space-md);
    background:var(--bg-secondary); border-radius:var(--radius-md);
    border-left:3px solid var(--accent);
}
.improvement-item__num {
    font-family:var(--font-mono); font-size:0.7rem; font-weight:700;
    color:var(--accent-light); min-width:24px; flex-shrink:0; padding-top:2px;
}
.improvement-item__text { font-size:0.8rem; color:var(--text-secondary); line-height:1.5; }
.improvement-item__text strong { color:var(--text-primary); }


/* ═══════════════════ FOOTER ═══════════════════ */
.footer {
    text-align:center; padding:var(--space-lg) var(--space-md);
    border-top:1px solid var(--surface-2); color:var(--text-tertiary); font-size:0.75rem;
    margin-bottom: var(--space-xl); /* Extra space above bottom nav */
}
.footer__tech { font-family:var(--font-mono); font-size:0.65rem; margin-top:var(--space-xs); }


/* ═══════════════════ ANIMATIONS ═══════════════════ */
@keyframes pulse { 0%,100%{opacity:1;} 50%{opacity:0.5;} }
.status--online::before {
    content:''; display:inline-block; width:6px; height:6px;
    border-radius:50%; background:var(--success); margin-right:4px; animation:pulse 2s infinite;
}
@keyframes fadeIn { from{opacity:0;transform:translateY(8px);} to{opacity:1;transform:translateY(0);} }
.device-card, .stat-card, .api-card, .info-card { animation:fadeIn 0.35s ease backwards; }
.device-card:nth-child(1){animation-delay:0.03s;}
.device-card:nth-child(2){animation-delay:0.06s;}
.device-card:nth-child(3){animation-delay:0.09s;}
.device-card:nth-child(4){animation-delay:0.12s;}
.device-card:nth-child(5){animation-delay:0.15s;}
.device-card:nth-child(6){animation-delay:0.18s;}


/* ═══════════════════ UTILITY CLASSES ═══════════════════ */
.u-mono { font-family:var(--font-mono); }
.u-muted { color:var(--text-secondary); }
.u-small { font-size:0.8rem; }
.u-center { text-align:center; }
.u-mb-sm { margin-bottom:var(--space-sm); }
.u-mb-md { margin-bottom:var(--space-md); }
.u-mb-lg { margin-bottom:var(--space-lg); }
.u-gap-md { gap:var(--space-md); }


/* ═══════════════════════════════════════════════════════
   TABLET (≥600px)
   ═══════════════════════════════════════════════════════ */
@media (min-width: 600px) {
    .device-grid       { grid-template-columns: repeat(2, 1fr); }
    .api-grid          { grid-template-columns: repeat(2, 1fr); }
    .improvement-grid  { grid-template-columns: repeat(2, 1fr); }
    .overview-map      { height: 300px; }
    .device-map        { height: 350px; }
    .stats-row         { grid-template-columns: repeat(3, 1fr); gap:var(--space-md); }
}


/* ═══════════════════════════════════════════════════════
   DESKTOP (≥768px)
   ═══════════════════════════════════════════════════════ */
@media (min-width: 768px) {
    :root { --bottom-nav-height: 0px; }

    body { padding-bottom: 0; }

    /* Hide bottom nav on desktop */
    .bottom-nav { display: none; }

    /* Restore top bar features */
    .top-bar { padding:var(--space-sm) var(--space-xl); height:60px; }
    .top-bar__title { font-size:1.2rem; }
    .top-bar__device-id { display:inline-block; }
    .top-bar__clock  { display:block; }
    .top-bar__refresh { display:block; }
    .top-bar--hidden { transform:none; } /* Don't hide on scroll for desktop */

    .container { padding:var(--space-xl); }
    .section-title { font-size:1.125rem; }

    .device-grid { grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap:var(--space-lg); }
    .map-gauge-row { grid-template-columns: 2fr 1fr; gap:var(--space-xl); }
    .device-map  { height:400px; }
    .overview-map { height:350px; }
    .stats-row { grid-template-columns: repeat(6, 1fr); }
    .api-grid { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap:var(--space-lg); }

    .stat-card { padding:var(--space-md); }
    .stat-card__icon { font-size:1.5rem; }
    .stat-card__value { font-size:1rem; }

    .device-card { padding:var(--space-lg); }
    .device-card:hover { transform:translateY(-2px); }

    .data-table { font-size:0.8rem; }
    .data-table th { font-size:0.7rem; padding:var(--space-sm) var(--space-md); }
    .data-table td { padding:var(--space-sm) var(--space-md); }

    .info-card { padding:var(--space-xl); }
}


/* ═══════════════════════════════════════════════════════
   LARGE DESKTOP (≥1200px)
   ═══════════════════════════════════════════════════════ */
@media (min-width: 1200px) {
    .container { padding:var(--space-xl) var(--space-2xl); }
}
/* ═══════════════════ PHASE 2: DASHBOARD ENHANCEMENTS ═══════════════════ */

/* Status Chips (Top horizontal scroll) */
.status-chips {
    display: flex;
    overflow-x: auto;
    gap: var(--space-sm);
    padding-bottom: var(--space-md);
    scrollbar-width: none;
    -ms-overflow-style: none;
    -webkit-overflow-scrolling: touch;
}
.status-chips::-webkit-scrollbar { display: none; }

.chip {
    flex: 0 0 auto;
    min-width: 90px;
    background: var(--surface-1);
    border: 1px solid var(--surface-2);
    border-radius: var(--radius-md);
    padding: var(--space-sm);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-fast);
}
.chip:hover { border-color: var(--accent); }
.chip--active { 
    background: var(--accent-glow); 
    border-color: var(--accent); 
    box-shadow: var(--shadow-glow); 
}
.chip__count { font-size: 1rem; font-weight: 700; display: block; }
.chip__label { font-size: 0.6rem; color: var(--text-tertiary); text-transform: uppercase; letter-spacing: 0.05em; }

/* FAB (Floating Action Button) - Add Device */
.fab {
    position: fixed;
    right: var(--space-lg);
    bottom: calc(var(--bottom-nav-height) + var(--space-lg));
    z-index: 1001;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--accent);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    box-shadow: var(--shadow-lg);
    cursor: pointer;
    transition: all var(--transition-normal);
    border: none;
}
.fab:hover { transform: scale(1.1) rotate(90deg); background: var(--accent-light); }
.fab:active { transform: scale(0.95); }

/* Modal Styles */
.modal-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.8);
    backdrop-filter: blur(8px);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-md);
    opacity: 0; pointer-events: none;
    transition: opacity var(--transition-normal);
}
.modal-overlay--visible { opacity: 1; pointer-events: auto; }

.modal-content {
    background: var(--bg-secondary);
    border: 1px solid var(--surface-3);
    border-radius: var(--radius-xl);
    width: 100%;
    max-width: 450px;
    padding: var(--space-xl);
    transform: translateY(20px);
    transition: transform var(--transition-normal);
}
.modal-overlay--visible .modal-content { transform: translateY(0); }

.modal-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: var(--space-lg); }
.modal-title { font-size: 1.25rem; font-weight: 700; color: var(--accent-light); }
.modal-close { background: none; border: none; color: var(--text-tertiary); font-size: 1.5rem; cursor: pointer; }

/* Enhanced Device Cards */
.device-card__address {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    line-height: 1.4;
    min-height: 2.8em;
}

.device-card__stats--compact {
    grid-template-columns: repeat(3, 1fr);
    border-top: 1px solid var(--surface-2);
    padding-top: var(--space-sm);
}

/* Forms */
.form-group { margin-bottom: var(--space-md); }
.form-label { display: block; font-size: 0.75rem; font-weight: 600; color: var(--text-tertiary); margin-bottom: var(--space-xs); }
.form-input {
    width: 100%;
    background: var(--surface-1);
    border: 1px solid var(--surface-3);
    border-radius: var(--radius-md);
    padding: var(--space-sm) var(--space-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.9rem;
    transition: border-color var(--transition-fast);
}
.form-input:focus { outline: none; border-color: var(--accent); }

.btn-primary {
    width: 100%;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    padding: var(--space-sm);
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-top: var(--space-md);
}
.btn-primary:hover { background: var(--accent-light); transform: translateY(-1px); }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; }

@media (min-width: 768px) {
    .status-chips { overflow: visible; justify-content: flex-start; gap: var(--space-lg); margin-bottom: var(--space-xl); }
    .chip { min-width: 120px; padding: var(--space-md); }
}
/* ═══════════════════ PHASE 2: PLAYBACK & SIMULATOR ═══════════════════ */

/* History Playback Controls */
.playback-controls {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    background: var(--surface-1);
    border: 1px solid var(--surface-2);
    border-radius: var(--radius-lg);
    padding: var(--space-sm) var(--space-md);
    margin-top: var(--space-md);
}
.playback-slider {
    flex: 1;
    accent-color: var(--success);
    height: 6px;
    border-radius: 9999px;
    cursor: pointer;
}
.btn-playback {
    background: var(--accent);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.25rem;
}

/* Date Pickers */
.date-picker-row {
    display: grid;
    grid-template-columns: 1fr 1fr auto;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
}

/* Simulator Panel in Device Page */
.simulator-tab {
    background: hsla(145, 65%, 42%, 0.05);
    border: 1px dashed var(--success);
    border-radius: var(--radius-lg);
    padding: var(--space-md);
    margin-top: var(--space-xl);
}
.sim-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-sm);
}

/* Stop Marker Popup */
.stop-popup { text-align: center; min-width: 150px; }
.stop-popup__title { font-weight: 700; color: var(--danger); margin-bottom: var(--space-xs); }
.stop-popup__time { font-size: 0.8rem; color: var(--text-secondary); }

@media (min-width: 768px) {
    .sim-grid { grid-template-columns: repeat(4, 1fr); }
}