/* =========================================================================
   Fuel Analytics — Design System
   --------------------------------------------------------------------------
   A small, deliberate set of tokens and primitives. All colors, shadows,
   radii, and spacing values here. Components below build on these tokens.
   Inspired by Linear / Stripe / Vercel dashboards.
   ========================================================================= */

:root {
  /* --- Color: surfaces ------------------------------------------------- */
  --color-bg:               #f7f8fa;
  --color-bg-subtle:        #eef0f4;
  --color-surface:          #ffffff;
  --color-surface-2:        #fafbfc;
  --color-border:           #e4e7ec;
  --color-border-strong:    #d0d5dd;
  --color-divider:          #eef0f4;

  /* --- Color: text ----------------------------------------------------- */
  --color-text:             #101828;
  --color-text-secondary:   #475467;
  --color-text-tertiary:    #667085;
  --color-text-inverse:     #ffffff;
  --color-text-muted:       #98a2b3;

  /* --- Color: brand & accents ----------------------------------------- */
  --color-brand-50:         #eff4ff;
  --color-brand-100:        #d6e1ff;
  --color-brand-500:        #2e5aac;
  --color-brand-600:        #1f3f87;
  --color-brand-700:        #182f64;
  --color-brand-900:        #0c1a3a;

  --color-accent:           #2e5aac;

  /* --- Color: semantic ------------------------------------------------- */
  --color-success-bg:       #ecfdf3;
  --color-success-border:   #abefc6;
  --color-success-fg:       #027a48;
  --color-success-strong:   #039855;

  --color-warning-bg:       #fffaeb;
  --color-warning-border:   #fedf89;
  --color-warning-fg:       #b54708;
  --color-warning-strong:   #dc6803;

  --color-danger-bg:        #fef3f2;
  --color-danger-border:    #fda29b;
  --color-danger-fg:        #b42318;
  --color-danger-strong:    #d92d20;

  --color-info-bg:          #eff8ff;
  --color-info-border:      #b2ddff;
  --color-info-fg:          #175cd3;

  /* --- Color: data viz ------------------------------------------------- */
  --color-fuel:             #2e5aac;
  --color-refuel:           #039855;
  --color-anomaly:          #d92d20;
  --color-speed:            #98a2b3;

  /* --- Typography ------------------------------------------------------ */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI',
               Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, 'JetBrains Mono', Menlo,
               Consolas, 'Liberation Mono', monospace;

  /* --- Spacing scale (4-pt grid) -------------------------------------- */
  --space-1:  4px;
  --space-2:  8px;
  --space-3:  12px;
  --space-4:  16px;
  --space-5:  20px;
  --space-6:  24px;
  --space-8:  32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;

  /* --- Radii ----------------------------------------------------------- */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-pill: 999px;

  /* --- Shadows --------------------------------------------------------- */
  --shadow-xs: 0 1px 2px rgba(16, 24, 40, 0.04);
  --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06), 0 1px 3px rgba(16, 24, 40, 0.06);
  --shadow-md: 0 2px 4px -2px rgba(16, 24, 40, 0.06), 0 4px 8px -2px rgba(16, 24, 40, 0.10);
  --shadow-lg: 0 4px 6px -2px rgba(16, 24, 40, 0.04), 0 12px 16px -4px rgba(16, 24, 40, 0.08);
  --shadow-xl: 0 8px 8px -4px rgba(16, 24, 40, 0.04), 0 20px 24px -4px rgba(16, 24, 40, 0.10);
  --shadow-focus: 0 0 0 4px rgba(46, 90, 172, 0.15);

  /* --- Header / nav ---------------------------------------------------- */
  --header-bg: linear-gradient(180deg, #0c1a3a 0%, #182f64 100%);
  --header-fg: rgba(255, 255, 255, 0.92);
  --header-fg-muted: rgba(255, 255, 255, 0.62);

  /* --- Animation ------------------------------------------------------- */
  --motion-fast:  120ms cubic-bezier(0.4, 0, 0.2, 1);
  --motion-base:  180ms cubic-bezier(0.4, 0, 0.2, 1);
  --motion-slow:  280ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ==========================================================================
   Reset / base
   ========================================================================== */

*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }

html { -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-sans);
  font-feature-settings: 'cv02', 'cv03', 'cv04', 'cv11';
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a { color: inherit; text-decoration: none; }
a:hover { color: var(--color-brand-500); }

img, svg { display: block; max-width: 100%; }

button { font-family: inherit; cursor: pointer; }

input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.25;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

h1 { font-size: 1.5rem; }
h2 { font-size: 1.125rem; }
h3 { font-size: 1rem; }

table { border-collapse: collapse; width: 100%; }

::selection { background: var(--color-brand-100); color: var(--color-brand-700); }

/* ==========================================================================
   Layout
   ========================================================================== */

.container {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 var(--space-8);
}

@media (max-width: 768px) {
  .container { padding: 0 var(--space-4); }
}

main.container { padding-top: var(--space-8); padding-bottom: var(--space-12); }

/* ==========================================================================
   Header / top navigation
   ========================================================================== */

.app-header {
  background: var(--header-bg);
  color: var(--header-fg);
  padding: var(--space-4) 0;
  border-bottom: 1px solid rgba(255,255,255,0.05);
  box-shadow: var(--shadow-sm);
  position: relative;
  z-index: 50;
}

.app-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  flex-wrap: wrap;
}

.app-header .brand {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.app-header .brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  background: rgba(255,255,255,0.1);
  color: var(--color-text-inverse);
}

.app-header h1 {
  color: var(--color-text-inverse);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.app-header .nav-links {
  display: flex;
  gap: var(--space-1);
  align-items: center;
  margin-left: var(--space-4);
}

.app-header .nav-link {
  color: var(--header-fg-muted);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: background var(--motion-fast), color var(--motion-fast);
}
.app-header .nav-link:hover {
  background: rgba(255,255,255,0.08);
  color: var(--color-text-inverse);
}
.app-header .nav-link.is-active {
  background: rgba(255,255,255,0.12);
  color: var(--color-text-inverse);
}

.app-header .header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}

/* ==========================================================================
   Buttons
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  border: 1px solid transparent;
  background: transparent;
  color: var(--color-text);
  transition: background var(--motion-fast), border-color var(--motion-fast), box-shadow var(--motion-fast), transform var(--motion-fast);
  cursor: pointer;
  white-space: nowrap;
  line-height: 1;
}
.btn:focus-visible { outline: none; box-shadow: var(--shadow-focus); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-primary {
  background: var(--color-brand-500);
  color: var(--color-text-inverse);
  border-color: var(--color-brand-500);
}
.btn-primary:hover { background: var(--color-brand-600); border-color: var(--color-brand-600); color: var(--color-text-inverse); }

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border-color: var(--color-border-strong);
}
.btn-secondary:hover { background: var(--color-surface-2); border-color: var(--color-text-tertiary); }

.btn-ghost {
  background: transparent;
  color: var(--color-text-secondary);
}
.btn-ghost:hover { background: var(--color-bg-subtle); color: var(--color-text); }

.btn-on-dark {
  background: rgba(255,255,255,0.1);
  color: var(--color-text-inverse);
  border-color: rgba(255,255,255,0.18);
}
.btn-on-dark:hover { background: rgba(255,255,255,0.18); color: var(--color-text-inverse); }

.btn-sm { padding: 6px 10px; font-size: 0.8125rem; }
.btn-lg { padding: 12px 20px; font-size: 0.9375rem; }

.btn-icon {
  width: 32px; height: 32px;
  padding: 0;
  border-radius: var(--radius-sm);
}

/* ==========================================================================
   Cards / surfaces
   ========================================================================== */

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

.card-header {
  padding: var(--space-5) var(--space-6);
  border-bottom: 1px solid var(--color-divider);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.card-header h2 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
}

.card-body { padding: var(--space-6); }

/* --- Stat / summary card -------------------------------------------------- */

.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5) var(--space-6);
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
  transition: box-shadow var(--motion-base), transform var(--motion-base);
}
.stat-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--color-brand-500);
}
.stat-card.is-success::before { background: var(--color-success-strong); }
.stat-card.is-warning::before { background: var(--color-warning-strong); }
.stat-card.is-danger::before  { background: var(--color-danger-strong); }
.stat-card.is-neutral::before { background: var(--color-text-tertiary); }

.stat-card .stat-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-tertiary);
  text-transform: none;
  letter-spacing: 0;
}

.stat-card .stat-value {
  margin-top: var(--space-2);
  font-size: 1.875rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--color-text);
  font-feature-settings: 'tnum' 1;
}
.stat-card .stat-value .unit {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-tertiary);
  margin-left: 4px;
}

.stat-card.is-success .stat-value { color: var(--color-success-strong); }
.stat-card.is-warning .stat-value { color: var(--color-warning-strong); }
.stat-card.is-danger  .stat-value { color: var(--color-danger-strong); }

.stat-card .stat-meta {
  margin-top: var(--space-2);
  font-size: 0.8125rem;
  color: var(--color-text-tertiary);
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}

/* ==========================================================================
   Forms
   ========================================================================== */

.field { display: flex; flex-direction: column; gap: 6px; }
.field-label {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-secondary);
}
.field-help {
  font-size: 0.8125rem;
  color: var(--color-text-tertiary);
}

.input, .select {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.875rem;
  transition: border-color var(--motion-fast), box-shadow var(--motion-fast);
}
.input:hover, .select:hover { border-color: var(--color-text-tertiary); }
.input:focus, .select:focus {
  outline: none;
  border-color: var(--color-brand-500);
  box-shadow: var(--shadow-focus);
}

input[type=date].input { padding: 7px 10px; }

/* --- Switch (toggle) ------------------------------------------------------ */

.switch-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-divider);
}
.switch-row:last-child { border-bottom: none; }
.switch-text { flex: 1; }
.switch-text .switch-title {
  font-weight: 500;
  font-size: 0.9375rem;
  color: var(--color-text);
}
.switch-text .switch-desc {
  margin-top: 2px;
  font-size: 0.8125rem;
  color: var(--color-text-tertiary);
}
.switch {
  position: relative;
  display: inline-block;
  width: 38px;
  height: 22px;
  flex-shrink: 0;
}
.switch input { opacity: 0; width: 0; height: 0; }
.switch .slider {
  position: absolute;
  inset: 0;
  background: var(--color-border-strong);
  border-radius: var(--radius-pill);
  transition: background var(--motion-base);
}
.switch .slider::before {
  content: '';
  position: absolute;
  top: 2px; left: 2px;
  width: 18px; height: 18px;
  background: #fff;
  border-radius: 50%;
  box-shadow: var(--shadow-xs);
  transition: transform var(--motion-base);
}
.switch input:checked + .slider { background: var(--color-brand-500); }
.switch input:checked + .slider::before { transform: translateX(16px); }
.switch input:focus-visible + .slider { box-shadow: var(--shadow-focus); }

/* ==========================================================================
   Tables
   ========================================================================== */

.table-wrap { overflow-x: auto; }

.table {
  width: 100%;
  font-size: 0.875rem;
  font-feature-settings: 'tnum' 1;
}

.table thead th {
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-tertiary);
  padding: 12px 20px;
  text-align: left;
  background: var(--color-surface-2);
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
}

.table tbody td {
  padding: 14px 20px;
  border-bottom: 1px solid var(--color-divider);
  vertical-align: middle;
}

.table tbody tr { transition: background var(--motion-fast); }
.table tbody tr:hover { background: var(--color-surface-2); }
.table tbody tr:last-child td { border-bottom: none; }

.table .num { text-align: right; font-variant-numeric: tabular-nums; }
.table .muted { color: var(--color-text-tertiary); }

/* ==========================================================================
   Badges
   ========================================================================== */

.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
  font-size: 0.75rem;
  font-weight: 500;
  line-height: 1.4;
  border: 1px solid transparent;
  white-space: nowrap;
}
.badge-success { background: var(--color-success-bg); color: var(--color-success-fg); border-color: var(--color-success-border); }
.badge-warning { background: var(--color-warning-bg); color: var(--color-warning-fg); border-color: var(--color-warning-border); }
.badge-danger  { background: var(--color-danger-bg);  color: var(--color-danger-fg);  border-color: var(--color-danger-border); }
.badge-info    { background: var(--color-info-bg);    color: var(--color-info-fg);    border-color: var(--color-info-border); }
.badge-neutral { background: var(--color-bg-subtle);  color: var(--color-text-secondary); border-color: var(--color-border); }

.badge .lucide { width: 12px; height: 12px; }

/* ==========================================================================
   Banner / message
   ========================================================================== */

.banner {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  border: 1px solid transparent;
}
.banner-success { background: var(--color-success-bg); color: var(--color-success-fg); border-color: var(--color-success-border); }
.banner-warning { background: var(--color-warning-bg); color: var(--color-warning-fg); border-color: var(--color-warning-border); }
.banner-danger  { background: var(--color-danger-bg);  color: var(--color-danger-fg);  border-color: var(--color-danger-border); }
.banner-info    { background: var(--color-info-bg);    color: var(--color-info-fg);    border-color: var(--color-info-border); }

/* ==========================================================================
   Profile / tenant menu (header dropdowns)
   ========================================================================== */

.menu {
  position: relative;
}
.menu-trigger {
  background: rgba(255,255,255,0.1);
  color: var(--color-text-inverse);
  border: 1px solid rgba(255,255,255,0.18);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.8125rem;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  transition: background var(--motion-fast);
}
.menu-trigger:hover { background: rgba(255,255,255,0.18); }
.menu-trigger .lucide { width: 14px; height: 14px; }
.menu-trigger.compact { padding: 5px 8px; }

.menu-panel {
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  min-width: 220px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: var(--space-1);
  z-index: 100;
  display: none;
}
.menu-panel.is-open { display: block; }

.menu-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  color: var(--color-text);
  text-decoration: none;
  transition: background var(--motion-fast);
}
.menu-item:hover { background: var(--color-bg-subtle); color: var(--color-text); }
.menu-item.is-active { background: var(--color-brand-50); color: var(--color-brand-700); font-weight: 500; }
.menu-item .lucide { width: 16px; height: 16px; opacity: 0.6; }
.menu-item.is-danger { color: var(--color-danger-fg); }
.menu-item.is-danger:hover { background: var(--color-danger-bg); }

.menu-divider {
  height: 1px;
  background: var(--color-divider);
  margin: 4px 0;
}

.menu-section {
  padding: 6px 10px;
  font-size: 0.6875rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-tertiary);
}

.user-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 10px 4px 4px;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: var(--radius-pill);
  color: var(--color-text-inverse);
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: background var(--motion-fast);
}
.user-chip:hover { background: rgba(255,255,255,0.18); }
.user-avatar {
  width: 26px; height: 26px;
  border-radius: 50%;
  background: linear-gradient(135deg, #4d7ed1 0%, #2e5aac 100%);
  color: #fff;
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 0.75rem;
  font-weight: 600;
  flex-shrink: 0;
}

/* Tenant pill for single-tenant users */
.tenant-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  color: var(--header-fg);
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  font-size: 0.8125rem;
  font-weight: 500;
}
.tenant-pill .lucide { width: 12px; height: 12px; opacity: 0.8; }

/* ==========================================================================
   Lucide icon defaults (loaded via CDN)
   ========================================================================== */

.lucide {
  width: 16px;
  height: 16px;
  stroke-width: 2;
  flex-shrink: 0;
  vertical-align: -2px;
}
.lucide-lg { width: 20px; height: 20px; }
.lucide-xl { width: 24px; height: 24px; }

/* ==========================================================================
   Utilities
   ========================================================================== */

.text-success { color: var(--color-success-strong); }
.text-warning { color: var(--color-warning-strong); }
.text-danger  { color: var(--color-danger-strong); }
.text-muted   { color: var(--color-text-tertiary); }
.text-mono    { font-family: var(--font-mono); }

.font-tabular { font-variant-numeric: tabular-nums; font-feature-settings: 'tnum' 1; }

.flex { display: flex; }
.flex-col { display: flex; flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.flex-wrap { flex-wrap: wrap; }
.flex-1 { flex: 1; }

.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }

.hidden { display: none !important; }

@media (max-width: 640px) {
  .hide-sm { display: none; }
  .stat-card .stat-value { font-size: 1.5rem; }
  h1 { font-size: 1.25rem; }
}