/* ========================================================================== 
   Variables
   ========================================================================== */

:root {
  /* Colors */
  --color-background: #0f172a; /* deep navy background */
  --color-surface: #111827; /* slightly lighter surface */
  --color-surface-alt: #1f2933; /* cards, panels */
  --color-text: #e5e7eb; /* light gray text */
  --color-text-muted: #9ca3af;
  --color-border-subtle: #1f2937;
  --color-border-strong: #4b5563;

  --color-primary: #2563eb; /* deep blue primary */
  --color-primary-soft: rgba(37, 99, 235, 0.12);
  --color-primary-strong: #1d4ed8;

  --color-accent: #ea580c; /* burnt orange accent */
  --color-accent-soft: rgba(234, 88, 12, 0.12);

  --color-success: #16a34a;
  --color-success-soft: rgba(22, 163, 74, 0.12);
  --color-warning: #eab308;
  --color-warning-soft: rgba(234, 179, 8, 0.12);
  --color-danger: #dc2626;
  --color-danger-soft: rgba(220, 38, 38, 0.12);

  --color-neutral-50: #f9fafb;
  --color-neutral-100: #f3f4f6;
  --color-neutral-200: #e5e7eb;
  --color-neutral-300: #d1d5db;
  --color-neutral-400: #9ca3af;
  --color-neutral-500: #6b7280;
  --color-neutral-600: #4b5563;
  --color-neutral-700: #374151;
  --color-neutral-800: #111827;
  --color-neutral-900: #020617;

  /* Typography */
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji",
    "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
  --font-mono: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;

  --font-size-xs: 0.75rem; /* 12px */
  --font-size-sm: 0.875rem; /* 14px */
  --font-size-base: 1rem; /* 16px */
  --font-size-lg: 1.125rem; /* 18px */
  --font-size-xl: 1.25rem; /* 20px */
  --font-size-2xl: 1.5rem; /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem; /* 36px */

  --line-height-tight: 1.2;
  --line-height-snug: 1.35;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.7;

  /* Spacing scale (px) */
  --space-0: 0;
  --space-1: 0.25rem; /* 4px */
  --space-2: 0.5rem; /* 8px */
  --space-3: 0.75rem; /* 12px */
  --space-4: 1rem; /* 16px */
  --space-5: 1.25rem; /* 20px */
  --space-6: 1.5rem; /* 24px */
  --space-8: 2rem; /* 32px */
  --space-10: 2.5rem; /* 40px */
  --space-12: 3rem; /* 48px */
  --space-16: 4rem; /* 64px */
  --space-20: 5rem; /* 80px */
  --space-24: 6rem; /* 96px */

  /* Radius */
  --radius-sm: 0.25rem; /* 4px */
  --radius-md: 0.5rem; /* 8px */
  --radius-lg: 0.75rem; /* 12px */
  --radius-xl: 1rem; /* 16px */
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.4);
  --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.45);
  --shadow-lg: 0 18px 45px rgba(15, 23, 42, 0.6);

  /* Transitions */
  --transition-fast: 120ms ease-out;
  --transition-normal: 180ms ease-out;
  --transition-slow: 240ms ease-out;

  /* Layout */
  --container-max-width: 1200px;
}

/* ========================================================================== 
   Reset / Normalize
   ========================================================================== */

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

html,
body,
div,
span,
applet,
object,
iframe,
h1,
h2,
h3,
h4,
h5,
h6,
p,
blockquote,
pre,
a,
abbr,
acronym,
address,
big,
cite,
code,
del,
dfn,
em,
img,
ins,
kbd,
q,
s,
samp,
small,
strike,
strong,
sub,
sup,
tt,
var,
b,
u,
i,
center,
dl,
dt,
dd,
ol,
ul,
li,
fieldset,
form,
label,
legend,
table,
caption,
tbody,
tfoot,
thead,
tr,
th,
td,
article,
aside,
canvas,
details,
embed,
figure,
figcaption,
footer,
header,
hgroup,
menu,
nav,
output,
ruby,
section,
summary,
time,
mark,
audio,
video {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 100%;
  font: inherit;
  vertical-align: baseline;
}

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

body {
  line-height: 1;
}

article,
aside,
footer,
header,
nav,
section,
main {
  display: block;
}

ol,
ul {
  list-style: none;
}

blockquote,
q {
  quotes: none;
}

blockquote::before,
blockquote::after,
q::before,
q::after {
  content: "";
  content: none;
}

table {
  border-collapse: collapse;
  border-spacing: 0;
}

img,
svg,
video,
canvas,
audio,
iframe,
embed,
object {
  display: block;
  max-width: 100%;
}

img,
video {
  height: auto;
}

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
  background: none;
  border-radius: 0;
}

button {
  cursor: pointer;
}

button:disabled,
[aria-disabled="true"] {
  cursor: not-allowed;
}

/* Remove default focus outline, we'll re-add with :focus-visible */
:focus {
  outline: none;
}

/* ========================================================================== 
   Base Styles
   ========================================================================== */

body {
  min-height: 100vh;
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: var(--line-height-relaxed);
  color: var(--color-text);
  background-color: var(--color-background);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

main {
  min-height: 60vh;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 600;
  line-height: var(--line-height-tight);
  color: var(--color-neutral-50);
}

h1 {
  font-size: clamp(2rem, 3vw, var(--font-size-4xl));
  margin-bottom: var(--space-4);
}

h2 {
  font-size: clamp(1.75rem, 2.4vw, var(--font-size-3xl));
  margin-bottom: var(--space-3);
}

h3 {
  font-size: clamp(1.5rem, 2vw, var(--font-size-2xl));
  margin-bottom: var(--space-3);
}

h4 {
  font-size: var(--font-size-xl);
  margin-bottom: var(--space-2);
}

h5 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--space-2);
}

h6 {
  font-size: var(--font-size-base);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-2);
}

p {
  margin-bottom: var(--space-4);
  color: var(--color-text);
}

p:last-child {
  margin-bottom: 0;
}

strong,
b {
  font-weight: 600;
}

small {
  font-size: var(--font-size-sm);
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-normal);
}

a:hover {
  color: var(--color-primary-strong);
}

a:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

code,
pre {
  font-family: var(--font-mono);
}

hr {
  border: 0;
  border-top: 1px solid var(--color-border-subtle);
  margin: var(--space-6) 0;
}

/* ========================================================================== 
   Accessibility & Motion
   ========================================================================== */

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

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

/* Layout container */

.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

@media (min-width: 1024px) {
  .container {
    padding-left: var(--space-6);
    padding-right: var(--space-6);
  }
}

/* Flex utilities */

.flex {
  display: flex;
}

.inline-flex {
  display: inline-flex;
}

.flex-row {
  flex-direction: row;
}

.flex-column {
  flex-direction: column;
}

.flex-wrap {
  flex-wrap: wrap;
}

.items-center {
  align-items: center;
}

.items-start {
  align-items: flex-start;
}

.items-end {
  align-items: flex-end;
}

.justify-center {
  justify-content: center;
}

.justify-between {
  justify-content: space-between;
}

.justify-end {
  justify-content: flex-end;
}

.gap-2 {
  gap: var(--space-2);
}

.gap-4 {
  gap: var(--space-4);
}

.gap-6 {
  gap: var(--space-6);
}

/* Grid utilities */

.grid {
  display: grid;
}

.grid-2-cols {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3-cols {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4-cols {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.grid-gap-4 {
  gap: var(--space-4);
}

.grid-gap-6 {
  gap: var(--space-6);
}

@media (max-width: 768px) {
  .grid-2-cols,
  .grid-3-cols,
  .grid-4-cols {
    grid-template-columns: minmax(0, 1fr);
  }
}

/* Visually hidden (screen reader only) */

.sr-only {
  border: 0;
  clip: rect(0 0 0 0);
  height: 1px;
  width: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  position: absolute;
  white-space: nowrap;
}

/* Spacing utilities (y-axis) */

.section {
  padding-top: var(--space-10);
  padding-bottom: var(--space-10);
}

.section-tight {
  padding-top: var(--space-6);
  padding-bottom: var(--space-6);
}

/* ========================================================================== 
   Components
   ========================================================================== */

/* Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  font-size: var(--font-size-sm);
  font-weight: 500;
  line-height: 1.2;
  text-decoration: none;
  background-color: var(--color-neutral-800);
  color: var(--color-neutral-50);
  transition:
    background-color var(--transition-normal),
    color var(--transition-normal),
    border-color var(--transition-normal),
    box-shadow var(--transition-fast),
    transform var(--transition-fast);
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  border-color: rgba(15, 23, 42, 0.5);
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.btn-outline {
  background-color: transparent;
  border-color: var(--color-border-strong);
  color: var(--color-neutral-50);
}

.btn-outline:hover {
  background-color: rgba(15, 23, 42, 0.7);
}

.btn-ghost {
  background-color: transparent;
  color: var(--color-neutral-100);
}

.btn-ghost:hover {
  background-color: rgba(15, 23, 42, 0.8);
}

.btn-sm {
  padding: 0.4rem 0.9rem;
  font-size: var(--font-size-xs);
}

.btn-lg {
  padding: 0.8rem 1.6rem;
  font-size: var(--font-size-base);
}

.btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

.btn:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.45;
  box-shadow: none;
  transform: none;
}

/* Form controls */

.input,
select,
textarea {
  width: 100%;
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-subtle);
  background-color: rgba(15, 23, 42, 0.8);
  color: var(--color-neutral-50);
  font-size: var(--font-size-sm);
  line-height: var(--line-height-normal);
  transition:
    border-color var(--transition-normal),
    box-shadow var(--transition-normal),
    background-color var(--transition-normal);
}

.input::placeholder,
textarea::placeholder {
  color: var(--color-text-muted);
}

.input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 1px var(--color-primary-soft);
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.input[aria-invalid="true"],
.input.error {
  border-color: var(--color-danger);
  box-shadow: 0 0 0 1px var(--color-danger-soft);
}

.field-label {
  display: block;
  margin-bottom: var(--space-1);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-neutral-100);
}

.field-helper {
  margin-top: var(--space-1);
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

.field-error {
  margin-top: var(--space-1);
  font-size: var(--font-size-xs);
  color: var(--color-danger);
}

/* Card */

.card {
  background: radial-gradient(circle at top left, rgba(37, 99, 235, 0.18), transparent 55%),
    radial-gradient(circle at bottom right, rgba(234, 88, 12, 0.16), transparent 55%),
    var(--color-surface);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(15, 23, 42, 0.7);
  box-shadow: var(--shadow-md);
  padding: var(--space-5);
  color: var(--color-text);
}

.card-header {
  margin-bottom: var(--space-4);
}

.card-title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-neutral-50);
}

.card-subtitle {
  margin-top: var(--space-1);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.card-body {
  font-size: var(--font-size-sm);
}

/* Tag / badge (for product specs, availability etc.) */

.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.15rem 0.5rem;
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: 500;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.badge-success {
  background-color: var(--color-success-soft);
  color: var(--color-success);
}

.badge-warning {
  background-color: var(--color-warning-soft);
  color: var(--color-warning);
}

.badge-danger {
  background-color: var(--color-danger-soft);
  color: var(--color-danger);
}

/* Simple chip for filters */

.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border-subtle);
  font-size: var(--font-size-xs);
  color: var(--color-text);
  background-color: rgba(15, 23, 42, 0.7);
  transition:
    background-color var(--transition-normal),
    border-color var(--transition-normal),
    color var(--transition-normal);
}

.chip--active {
  border-color: var(--color-primary);
  background-color: var(--color-primary-soft);
  color: var(--color-neutral-50);
}

/* Helper for subtle panels (filters, spec boxes) */

.surface-muted {
  background-color: rgba(15, 23, 42, 0.8);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-subtle);
}