/* ============================================================
   blog/blog.css — shared stylesheet for anatoliybabushka.com/blog/
   Plain CSS, no build step, no dependencies.
   Design decisions grounded in legibility research + WCAG 2.1.
   ============================================================ */

/* ----------------------------------------------------------
   1. Self-hosted Inter (variable font, weights 100–900)
   ---------------------------------------------------------- */
@font-face {
    font-family: 'Inter';
    font-style: normal;
    font-weight: 100 900;
    font-display: swap;
    src: url('/fonts/inter-latin-var.woff2') format('woff2');
}

/* ----------------------------------------------------------
   2. Modern minimal reset
   ---------------------------------------------------------- */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

img,
picture,
svg,
video {
    display: block;
    max-width: 100%;
    height: auto;
}

/* ----------------------------------------------------------
   3. Design tokens
   Contrast ratios on --bg #f6f6f4:
     --ink   #1a1a1a  → ~17 : 1  (WCAG AAA)
     --muted #5a5a57  →  ~6 : 1  (WCAG AA)
   ---------------------------------------------------------- */
:root {
    --bg:   #f6f6f4;
    --ink:  #1a1a1a;
    --muted: #5a5a57;
    --line: #dcdcd6;

    --sans: 'Inter', system-ui, -apple-system, 'Helvetica Neue', Arial, sans-serif;
    --mono: ui-monospace, 'SF Mono', Menlo, Monaco, 'Liberation Mono', monospace;
}

/* ----------------------------------------------------------
   4. Base typography
   font-size: 1.125rem ≈ 18 px — sits in the research sweet
   spot (16–20 px) for comfortable on-screen reading.
   line-height: 1.65 — generous enough for long prose.
   text-align: left — never justify (harms dyslexic readers
   and produces uneven word-spacing at narrow column widths).
   ---------------------------------------------------------- */
body {
    font-family: var(--sans);
    font-size: 1.125rem;
    line-height: 1.65;
    color: var(--ink);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    text-align: left;
}

/* ----------------------------------------------------------
   5. Content column
   max-width: 66ch — the ~66-character research optimum for
   comfortable reading (Bringhurst, Baymard, WCAG advisory).
   clamp() side padding means it never bleeds to the edge on
   narrow viewports, and the content survives a 200% zoom.
   ---------------------------------------------------------- */
.wrap {
    max-width: 66ch;
    margin-inline: auto;
    padding-inline: clamp(20px, 5vw, 28px);
}

/* ----------------------------------------------------------
   6. Headings
   rem units so they scale with the user's browser font
   preference (WCAG 1.4.4 Resize Text).
   line-height ~1.2 — tight enough for display, readable
   enough to avoid crowding when headings wrap.
   ---------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.02em;
    color: var(--ink);
}

h1 { font-size: 2rem;    margin-block-start: 2.5rem; }
h2 { font-size: 1.5rem;  margin-block-start: 2rem; }
h3 { font-size: 1.25rem; margin-block-start: 1.75rem; }
h4 { font-size: 1.125rem; margin-block-start: 1.5rem; }

/* First heading in a page section needs no top gap */
h1:first-child,
h2:first-child,
h3:first-child {
    margin-block-start: 0;
}

/* ----------------------------------------------------------
   7. Paragraphs & prose spacing
   1em bottom margin ensures comfortable vertical rhythm.
   ---------------------------------------------------------- */
p {
    margin-block: 1em;
}

p:last-child {
    margin-block-end: 0;
}

/* ----------------------------------------------------------
   8. Links
   color: inherit — link text always inherits --ink, so it
   passes WCAG 1.4.3 regardless of context.
   underline-offset: keeps descenders visible.
   focus-visible: 2 px solid ring — WCAG 2.4.7 Focus Visible.
   ---------------------------------------------------------- */
a {
    color: inherit;
    text-decoration: underline;
    text-underline-offset: 0.12em;
    text-decoration-thickness: 1px;
}

a:hover {
    text-decoration-thickness: 2px;
}

a:focus-visible {
    outline: 2px solid var(--ink);
    outline-offset: 2px;
    border-radius: 2px;
}

/* ----------------------------------------------------------
   9. Lists
   ---------------------------------------------------------- */
ul,
ol {
    padding-inline-start: 1.4em;
    margin-block: 1em;
}

li {
    margin-block: 0.35em;
}

li:last-child {
    margin-block-end: 0;
}

/* ----------------------------------------------------------
   10. Blockquote
   Left border + muted colour signals a quotation without
   heavy chrome. Italic is conventional for attribution.
   ---------------------------------------------------------- */
blockquote {
    border-inline-start: 3px solid var(--line);
    margin-inline: 0;
    margin-block: 1.5em;
    padding-inline-start: 1.25em;
    color: var(--muted);
    font-style: italic;
}

blockquote p {
    margin-block: 0.5em;
}

/* ----------------------------------------------------------
   11. Code
   ui-monospace resolves to the system monospace font on each
   platform (SF Mono / Cascadia / DejaVu Sans Mono).
   overflow: auto on pre lets wide code blocks scroll
   horizontally rather than breaking the layout.
   ---------------------------------------------------------- */
code,
kbd,
samp {
    font-family: var(--mono);
    font-size: 0.875em;
    background: rgba(0, 0, 0, 0.05);
    padding: 0.15em 0.35em;
    border-radius: 3px;
}

pre {
    font-family: var(--mono);
    font-size: 0.875rem;
    line-height: 1.55;
    background: rgba(0, 0, 0, 0.04);
    border: 1px solid var(--line);
    border-radius: 6px;
    padding: 1.1em 1.25em;
    overflow: auto;
    margin-block: 1.5em;
    -webkit-overflow-scrolling: touch;
}

pre code {
    background: none;
    padding: 0;
    border-radius: 0;
    font-size: inherit;
}

/* ----------------------------------------------------------
   12. Horizontal rule
   ---------------------------------------------------------- */
hr {
    border: none;
    border-block-start: 1px solid var(--line);
    margin-block: 2.5em;
}

/* ----------------------------------------------------------
   13. Post metadata line
   ---------------------------------------------------------- */
.post-meta {
    font-size: 0.875rem;
    color: var(--muted);
    margin-block: 0.5em 2em;
    letter-spacing: 0.01em;
}

.post-meta time {
    font-variant-numeric: tabular-nums;
}

/* ----------------------------------------------------------
   14. Page-level layout helpers
   ---------------------------------------------------------- */
.site-header {
    border-block-end: 1px solid var(--line);
    padding-block: 1.25rem;
}

.site-header .wrap {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
}

.site-header .site-name {
    font-size: 0.8125rem;
    font-family: var(--mono);
    letter-spacing: 0.14em;
    text-transform: uppercase;
    text-decoration: none;
    color: var(--ink);
    font-weight: 600;
}

.site-header nav a {
    font-size: 0.8125rem;
    font-family: var(--mono);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    text-decoration: none;
    color: var(--muted);
}

.site-header nav a:hover {
    color: var(--ink);
    text-decoration: none;
}

.site-footer {
    border-block-start: 1px solid var(--line);
    padding-block: 2rem;
    margin-block-start: 4rem;
    font-size: 0.8125rem;
    font-family: var(--mono);
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--muted);
}

.site-footer a {
    color: var(--muted);
    text-decoration: none;
}

.site-footer a:hover {
    color: var(--ink);
}

/* ----------------------------------------------------------
   15. Blog index — post list
   ---------------------------------------------------------- */
.post-list {
    list-style: none;
    padding: 0;
    margin-block: 2rem;
}

.post-list li {
    margin: 0;
    border-block-start: 1px solid var(--line);
    padding-block: 1.5rem;
}

.post-list li:last-child {
    border-block-end: 1px solid var(--line);
}

.post-list .post-title-link {
    font-size: 1.25rem;
    font-weight: 600;
    text-decoration: none;
    color: var(--ink);
    letter-spacing: -0.01em;
    line-height: 1.25;
}

.post-list .post-title-link:hover {
    text-decoration: underline;
    text-underline-offset: 0.12em;
}

.post-list .post-summary {
    margin-block: 0.35em 0;
    color: var(--muted);
    font-size: 1rem;
}

.post-list .post-meta {
    margin-block: 0 0.35em;
}

/* ----------------------------------------------------------
   16. Main content area vertical rhythm
   ---------------------------------------------------------- */
main {
    padding-block: 3rem 2rem;
}

/* Selection colour — matches homepage */
::selection {
    background: var(--ink);
    color: var(--bg);
}