/* ==========================================================================
   FilterEquiv: High-Tech Industrial Design System
   ========================================================================== */

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

ul, ol {
  list-style: none;
  margin: 0;
  padding: 0;
}

/* ---------- Custom Properties (Dark Theme Default) ---------- */
:root {
  /* Dark Industrial Palette */
  --color-bg:            hsl(222 24% 8%);
  --color-bg-elevated:   hsl(222 22% 11%);
  --color-bg-card:       hsl(222 20% 14%);
  --color-bg-card-hover: hsl(222 18% 18%);
  --color-surface:       hsl(222 18% 12%);
  --color-surface-hover: hsl(222 18% 16%);

  --color-text:          hsl(210 24% 94%);
  --color-text-muted:    hsl(215 15% 68%);
  --color-text-dim:      hsl(215 12% 48%);

  /* Technical Amber / Precision Orange Accent */
  --color-accent:        hsl(38 98% 54%);
  --color-accent-hover:  hsl(38 98% 46%);
  --color-accent-subtle: hsl(38 75% 15%);
  --color-accent-border: hsl(38 95% 55% / 0.35);

  --color-success:       hsl(152 68% 48%);
  --color-warning:       hsl(38 95% 55%);
  --color-danger:        hsl(356 75% 58%);
  --color-info:          hsl(205 90% 55%);

  --color-border:        hsl(222 16% 22%);
  --color-border-strong: hsl(222 16% 32%);

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', ui-monospace, monospace;

  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  1.875rem;
  --text-4xl:  2.25rem;
  --text-5xl:  3rem;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Radii */
  --radius-xs:  0.25rem;
  --radius-sm:  0.375rem;
  --radius-md:  0.5rem;
  --radius-lg:  0.75rem;
  --radius-xl:  1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm:   0 1px 2px hsl(0 0% 0% / .4);
  --shadow-md:   0 6px 16px hsl(0 0% 0% / .45);
  --shadow-lg:   0 12px 32px hsl(0 0% 0% / .55);
  --shadow-glow: 0 0 25px hsl(38 98% 54% / .2);

  /* Transitions */
  --ease-out: cubic-bezier(.16, 1, .3, 1);
  --transition-fast:   150ms var(--ease-out);
  --transition-normal: 250ms var(--ease-out);
  --transition-slow:   400ms var(--ease-out);

  /* Layout */
  --container-max: 1240px;
  --header-height: 68px;
}

/* ---------- Light Theme Overrides ---------- */
:root[data-theme="light"],
html[data-theme="light"] {
  --color-bg:            hsl(215 28% 97%);
  --color-bg-elevated:   hsl(0 0% 100%);
  --color-bg-card:       hsl(0 0% 100%);
  --color-bg-card-hover: hsl(215 20% 95%);
  --color-surface:       hsl(215 20% 93%);
  --color-surface-hover: hsl(215 20% 88%);

  --color-text:          hsl(222 28% 12%);
  --color-text-muted:    hsl(215 16% 38%);
  --color-text-dim:      hsl(215 12% 52%);

  --color-accent:        hsl(32 96% 42%);
  --color-accent-hover:  hsl(32 96% 36%);
  --color-accent-subtle: hsl(38 95% 92%);
  --color-accent-border: hsl(38 95% 55% / 0.45);

  --color-border:        hsl(215 20% 86%);
  --color-border-strong: hsl(215 20% 72%);

  --shadow-sm:   0 1px 2px hsl(222 20% 10% / .08);
  --shadow-md:   0 6px 16px hsl(222 20% 10% / .1);
  --shadow-lg:   0 12px 32px hsl(222 20% 10% / .14);
}

/* ---------- Base ---------- */
html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
  color-scheme: dark;
  overflow-x: clip;
  max-width: 100vw;
}

html[data-theme="light"] {
  color-scheme: light;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100dvh;
  overflow-x: clip;
  max-width: 100%;
}

/* ---------- Typography ---------- */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

h1 { font-size: var(--text-4xl); font-weight: 800; }
h2 { font-size: var(--text-3xl); font-weight: 700; }
h3 { font-size: var(--text-2xl); font-weight: 700; }
h4 { font-size: var(--text-xl); }

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}
a:hover {
  color: var(--color-accent-hover);
}

/* ---------- Container ---------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

/* ---------- Utility Classes ---------- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.text-muted   { color: var(--color-text-muted); }
.text-dim     { color: var(--color-text-dim); }
.text-accent  { color: var(--color-accent); }
.text-success { color: var(--color-success); }
.text-warning { color: var(--color-warning); }
.text-danger  { color: var(--color-danger); }

/* ---------- Badges ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-full);
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border: 1px solid transparent;
}

.badge--success {
  background: hsl(152 68% 48% / .12);
  color: var(--color-success);
  border-color: hsl(152 68% 48% / .25);
}

.badge--warning {
  background: hsl(38 95% 55% / .12);
  color: var(--color-warning);
  border-color: hsl(38 95% 55% / .25);
}

.badge--danger {
  background: hsl(356 75% 58% / .12);
  color: var(--color-danger);
  border-color: hsl(356 75% 58% / .25);
}

.badge--info {
  background: hsl(205 90% 55% / .12);
  color: var(--color-info);
  border-color: hsl(205 90% 55% / .25);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-5);
  border: none;
  border-radius: var(--radius-md);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
}

.btn--primary,
a.btn--primary,
button.btn--primary {
  background: var(--color-accent);
  color: hsl(222 24% 8%) !important;
  font-weight: 700;
}

.btn--primary:hover,
a.btn--primary:hover,
button.btn--primary:hover {
  background: var(--color-accent-hover);
  color: hsl(222 24% 8%) !important;
  box-shadow: var(--shadow-glow);
  transform: translateY(-1px);
}

.btn--ghost,
a.btn--ghost,
button.btn--ghost {
  background: var(--color-surface);
  color: var(--color-text-muted) !important;
  border: 1px solid var(--color-border);
}

.btn--ghost:hover,
a.btn--ghost:hover,
button.btn--ghost:hover {
  color: var(--color-text) !important;
  border-color: var(--color-border-strong);
  background: var(--color-surface-hover);
}

/* ---------- Cards ---------- */
.card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: all var(--transition-normal);
}
.card:hover {
  background: var(--color-bg-card-hover);
  border-color: var(--color-border-strong);
}

/* ---------- Search Component Styles ---------- */
.search-box-container {
  position: relative;
  width: 100%;
}

.search-input-group {
  display: flex;
  align-items: center;
  background: var(--color-bg-card);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-2xl);
  box-shadow: 0 12px 32px hsl(0 0% 0% / 0.5);
  padding: 8px 10px 8px 20px;
  gap: var(--space-3);
  min-height: 66px;
  transition: all var(--transition-fast);
}

.search-input-group:focus-within {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-glow), 0 16px 40px hsl(0 0% 0% / 0.6);
  background: var(--color-bg-elevated);
}

.search-icon-prefix {
  color: var(--color-text-dim);
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.search-main-input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  padding: var(--space-3) var(--space-2);
  font-family: var(--font-sans);
  font-size: 1.125rem;
  color: var(--color-text);
  min-width: 0;
}

.search-main-input::placeholder {
  color: var(--color-text-dim);
  font-size: 1rem;
}

.search-action-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--color-accent);
  color: hsl(222 24% 8%) !important;
  font-weight: 800;
  font-size: 1rem;
  border: none;
  border-radius: calc(var(--radius-2xl) - 8px);
  padding: 14px 28px;
  cursor: pointer;
  white-space: nowrap;
  flex-shrink: 0;
  transition: all var(--transition-fast);
}

.search-action-btn:hover {
  background: var(--color-accent-hover);
  box-shadow: var(--shadow-glow);
  transform: translateY(-1px);
}

/* Search Dropdown */
.search-dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  right: 0;
  width: 100%;
  max-height: 70vh;
  overflow-y: auto;
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-xl);
  box-shadow: 0 20px 50px hsl(0 0% 0% / 0.8), 0 0 0 1px hsl(38 95% 55% / 0.2);
  z-index: 999999;
  animation: dropdownIn 180ms var(--ease-out);
}

.dropdown-section {
  padding: var(--space-3);
}

.dropdown-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 700;
  color: var(--color-text-dim);
  padding: var(--space-2) var(--space-3);
}

.icon-verified {
  color: var(--color-success);
}

.dropdown-list {
  list-style: none;
}

.dropdown-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background var(--transition-fast);
}

.dropdown-item:hover {
  background: var(--color-bg-card-hover);
}

.item-meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.item-brand {
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-dim);
  font-weight: 600;
}

.item-ref {
  font-family: var(--font-mono);
  font-size: var(--text-base);
  color: var(--color-accent);
}

.item-type-badge {
  font-size: 0.7rem;
  color: var(--color-text-muted);
  background: var(--color-surface);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}

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

.item-equiv-count {
  font-size: var(--text-xs);
  color: var(--color-text-dim);
}

.item-arrow {
  color: var(--color-text-dim);
  transition: transform var(--transition-fast);
}

.dropdown-item:hover .item-arrow {
  color: var(--color-accent);
  transform: translateX(2px);
}

.dropdown-empty {
  padding: var(--space-6);
  text-align: center;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

.dropdown-direct-btn {
  margin-top: var(--space-3);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--text-sm);
}

.dropdown-direct-btn strong {
  color: var(--color-accent);
}

.dropdown-direct-btn:hover {
  background: var(--color-surface-hover);
  border-color: var(--color-accent);
}

.quick-tags-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 8px;
  padding: var(--space-2) var(--space-3);
  width: 100%;
  box-sizing: border-box;
}

.quick-tag-chip {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 8px 12px;
  cursor: pointer;
  width: 100%;
  box-sizing: border-box;
  transition: all var(--transition-fast);
}

.quick-tag-chip:hover {
  background: var(--color-surface-hover);
  border-color: var(--color-accent);
  transform: translateY(-1px);
}

.chip-brand {
  font-size: 0.68rem;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
}

.chip-ref {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 700;
  color: var(--color-accent);
}

@keyframes dropdownIn {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 640px) {
  .search-input-group {
    flex-direction: column;
    padding: var(--space-2);
    border-radius: var(--radius-lg);
  }
  .search-main-input {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    text-align: left;
    font-size: 0.95rem;
  }
  .search-action-btn {
    width: 100%;
    justify-content: center;
    border-radius: var(--radius-md);
    padding: var(--space-3);
  }
  .search-icon-prefix {
    display: none;
  }
  .quick-tags-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 6px;
    padding: 6px;
  }
  .quick-tag-chip {
    padding: 8px 10px;
  }
}

/* ---------- Header & Navigation Pills ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  height: 72px;
  background: hsl(222 24% 6% / 0.92);
  backdrop-filter: blur(20px) saturate(1.8);
  -webkit-backdrop-filter: blur(20px) saturate(1.8);
  border-bottom: 1px solid hsl(222 18% 18%);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: var(--space-4);
}

.main-nav {
  display: flex;
  align-items: center;
}

.nav-buttons-list {
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: hsl(222 20% 13%);
  border: 1px solid hsl(222 18% 22%);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  color: hsl(210 20% 88%) !important;
  text-decoration: none !important;
  box-shadow: 0 2px 6px hsl(0 0% 0% / 0.3);
  transition: all 180ms ease;
  white-space: nowrap;
}

.nav-btn .btn-icon {
  color: var(--color-accent);
  transition: transform 180ms ease;
}

.nav-btn:hover {
  background: hsl(222 22% 18%);
  border-color: var(--color-accent);
  color: #ffffff !important;
  transform: translateY(-1px);
  box-shadow: 0 4px 14px hsl(0 0% 0% / 0.5), 0 0 12px hsl(38 95% 55% / 0.15);
}

.nav-btn:hover .btn-icon {
  transform: scale(1.1);
}

.nav-btn--ghost {
  background: transparent;
  border-color: transparent;
  color: hsl(215 15% 65%) !important;
}

.nav-btn--ghost:hover {
  background: hsl(222 20% 15%);
  border-color: hsl(222 18% 25%);
}

.btn-header-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--color-accent-subtle);
  border: 1px solid var(--color-accent-border);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--color-accent) !important;
  text-decoration: none !important;
  box-shadow: 0 0 12px hsl(38 95% 55% / 0.1);
  transition: all var(--transition-fast);
}

.btn-header-cta:hover {
  background: var(--color-accent);
  color: hsl(222 24% 8%) !important;
  border-color: var(--color-accent);
  box-shadow: var(--shadow-glow);
  transform: translateY(-1px);
}

.btn-header-cta:hover .btn-icon {
  color: hsl(222 24% 8%) !important;
}

.btn-header-cta .btn-icon {
  color: var(--color-accent);
}

@media (max-width: 860px) {
  .main-nav {
    display: none;
  }
}