/*
  Responsive + Image Optimization Starter CSS (2025)
  --------------------------------------------------
  Drop-in stylesheet that gives you:
  - Fluid type/spacing with clamp()
  - Mobile-first media queries
  - Container queries (progressive enhancement)
  - Accessible reduced-motion fallbacks
  - Dark-mode support
  - Helpers for <img>, <picture>, responsive backgrounds, and SVG icons

  Usage:
    <link rel="stylesheet" href="/css/responsive-starter.css">
*/

/* 1) Design tokens */
:root {
  /* Typography scale */
  --step--2: clamp(0.7rem, 0.7rem + 0.1vw, 0.78rem);
  --step--1: clamp(0.85rem, 0.84rem + 0.2vw, 0.96rem);
  --step-0: clamp(1rem, 0.98rem + 0.3vw, 1.13rem);
  --step-1: clamp(1.15rem, 1.14rem + 0.4vw, 1.35rem);
  --step-2: clamp(1.33rem, 1.3rem + 0.6vw, 1.62rem);
  --step-3: clamp(1.6rem, 1.55rem + 0.8vw, 1.96rem);
  --step-4: clamp(1.92rem, 1.86rem + 1vw, 2.35rem);

  /* Layout scale */
  --space-1: clamp(0.5rem, 0.4rem + 0.4vw, 0.75rem);
  --space-2: clamp(1rem, 0.8rem + 0.8vw, 1.5rem);
  --space-3: clamp(1.5rem, 1.2rem + 1.2vw, 2.25rem);
  --space-4: clamp(2rem, 1.6rem + 1.6vw, 3rem);

  /* Color */
  --bg: #0b0c0f;
  --fg: #e8e8ea;
  --muted: #a0a3a8;
  --brand: #6ea8fe;

  /* Content width */
  --content: 68rem; /* ~1088px */
}

/* Dark mode auto */
@media (prefers-color-scheme: light) {
  :root {
    --bg: #ffffff;
    --fg: #121416;
    --muted: #4b5563;
    --brand: #2563eb;
  }
}

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

html {
  hanging-punctuation: first last;
}

body {
  margin: 0;
  font: 400 var(--step-0) / 1.55 system-ui, -apple-system, Segoe UI, Roboto,
    sans-serif;
  color: var(--fg);
  background: var(--bg);
}

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

/* 2) Container + fluid layout helpers */
.wrapper {
  width: min(100% - 2rem, var(--content));
  margin-inline: auto;
}

.stack > * + * {
  margin-block-start: var(--space-2);
}
.cluster {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  align-items: center;
}

.grid {
  display: grid;
  gap: var(--space-2);
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

/* 3) Media query breakpoints (mobile-first) */
@media (min-width: 37.5rem) {
  /* 600px - tablet */
  :root {
    --content: 72rem;
  }
}
@media (min-width: 56.25rem) {
  /* 900px - small laptop */
  :root {
    --content: 76rem;
  }
}
@media (min-width: 75rem) {
  /* 1200px - desktop */
  :root {
    --content: 82rem;
  }
}

/* 4) Container queries (progressive) */
.container {
  container-type: inline-size;
  container-name: card;
}

@container card (min-width: 28rem) {
  /* ~448px container */
  .card--media-right {
    grid-auto-flow: column;
    grid-auto-columns: 1fr 1fr;
  }
}

/* 5) Responsive media helpers */
.responsive-media {
  max-width: 100%;
  height: auto;
}

/* Picture + sizes utility (example) */
.responsive-img {
  width: 100%;
  height: auto;
}

/* Background image helper with image-set() (serve 1x/2x) */
.bg-cover {
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
}

/* 6) Reduced motion + prefers-contrast */
@media (prefers-reduced-motion: reduce) {
  :root {
    scroll-behavior: auto;
  }
  * {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

/* 7) Utility classes */
.flow > * + * {
  margin-block-start: var(--space-1);
}
.center {
  margin-inline: auto;
}
.hidden {
  display: none !important;
}
.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 1px, 1px);
  white-space: nowrap;
  border: 0;
}

/* 8) SVG-friendly defaults */
svg {
  height: auto;
}
.icon {
  inline-size: 1em;
  block-size: 1em;
  fill: currentColor;
}

/* 9) Example card pattern ready for container queries */
.card {
  display: grid;
  gap: var(--space-1);
  padding: var(--space-2);
  border-radius: 1rem;
  background: color-mix(in oklab, var(--fg) 8%, var(--bg));
  box-shadow: 0 0.25rem 1.25rem rgb(0 0 0 / 0.12);
}
.card img {
  border-radius: 0.75rem;
}

/* 10) Forms + buttons basics */
.header {
  font: inherit;
  border: 0;
  border-radius: 0.75rem;
  padding: 0.6em 1em;
  background: var(--brand);
  color: white;
}
a {
  text-decoration: none;
  color: var(--brand);
}
button,
.btn {
  font: inherit;
  border: 0;
  border-radius: 0.75rem;
  padding: 0.6em 1em;
  background: var(--brand);
  color: white;
  cursor: pointer;
}
a.btn {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.5em;
}

/* 11) Example responsive table */
.table {
  width: 100%;
  border-collapse: collapse;
  border-spacing: 0;
}
.table th,
.table td {
  padding: 0.6rem 0.8rem;
  border-bottom: 1px solid color-mix(in oklab, var(--fg) 15%, var(--bg));
}
.table--stack th {
  text-align: left;
}
@media (max-width: 40rem) {
  .table--stack thead {
    display: none;
  }
  .table--stack tr {
    display: grid;
    gap: 0.25rem;
    padding: 0.6rem 0;
  }
  .table--stack td::before {
    content: attr(data-label);
    font-weight: 600;
    display: block;
    color: var(--muted);
  }
}

/* --- ICON RENDERING FIX --- */
svg {
  display: inline-block;
  max-width: 100%;
  height: auto;
}
.icon {
  display: inline-flex;
  width: 1em;
  height: 1em;
  line-height: 1;
}
.icon svg {
  width: 1em;
  height: 1em;
  vertical-align: -0.125em;
}

/* End of starter */