/* inversegravity.net */

:root {
  --bg: #ffffff;
  --fg: #111111;
  --muted: #666666;
  --line: #e6e6e6;
  --code-bg: #f4f4f4;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #121212;
    --fg: #e6e6e6;
    --muted: #9a9a9a;
    --line: #2a2a2a;
    --code-bg: #1c1c1c;
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --bg: #121212;
  --fg: #e6e6e6;
  --muted: #9a9a9a;
  --line: #2a2a2a;
  --code-bg: #1c1c1c;
  color-scheme: dark;
}

/* base */

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

.wrapper {
  max-width: 42rem;
  min-height: 100vh;
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  flex-direction: column;
}

main, .page, .post { flex: 1; }

a {
  color: inherit;
  text-decoration: none;
}

a:hover { color: var(--muted); }

:focus-visible {
  outline: 2px solid var(--fg);
  outline-offset: 2px;
}

h1, h2, h3, h4 {
  line-height: 1.25;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 2.2em 0 0.6em;
}

h1 { font-size: 1.9rem; }
h2 { font-size: 1.35rem; }
h3 { font-size: 1.1rem; }
h4 { font-size: 1rem; }

p, ul, ol, table, pre, blockquote, figure { margin: 0 0 1.2em; }

ul, ol { padding-left: 1.3em; }
li { margin: 0.3em 0; }

hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 2.5rem 0;
}

img, video, iframe {
  max-width: 100%;
  height: auto;
}

strong, b { font-weight: 600; }

/* logos are black on a light-grey (#ccc) or white background: lift the
   background to pure white, then blend it away; invert in dark mode */

img.logo-mark,
img[src$="/inversegravity.png"],
img[src$="/icons-192.png"] {
  filter: brightness(1.25);
  mix-blend-mode: multiply;
}

:root[data-theme="dark"] img.logo-mark,
:root[data-theme="dark"] img[src$="/inversegravity.png"],
:root[data-theme="dark"] img[src$="/icons-192.png"] {
  filter: brightness(1.25) invert(1);
  mix-blend-mode: screen;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) img.logo-mark,
  :root:not([data-theme="light"]) img[src$="/inversegravity.png"],
  :root:not([data-theme="light"]) img[src$="/icons-192.png"] {
    filter: brightness(1.25) invert(1);
    mix-blend-mode: screen;
  }
}

/* language blocks: <html data-lang="de|en"> picks which [lang] block is shown */

html[data-lang="de"] body [lang="en"],
html[data-lang="en"] body [lang="de"] { display: none !important; }

/* header */

.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  padding: 2rem 0 1rem;
}

.brand {
  font-weight: 600;
  text-decoration: none;
  letter-spacing: -0.01em;
}

.brand span { font-weight: 400; color: var(--muted); }

.site-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 1.25rem;
  font-size: 0.95rem;
}

.site-nav a { text-decoration: none; color: var(--muted); }
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--fg); }

.controls {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
}

.controls button {
  font: inherit;
  font-size: 0.85rem;
  color: var(--muted);
  background: none;
  border: 0;
  padding: 0.25rem;
  cursor: pointer;
  line-height: 1;
}

.controls button:hover,
.controls button[aria-pressed="true"] { color: var(--fg); }

.lang-switch { display: inline-flex; align-items: center; gap: 0.1rem; }
.lang-switch button { text-transform: uppercase; letter-spacing: 0.05em; }
.lang-switch button[aria-pressed="true"] { font-weight: 600; }
.lang-switch .sep { color: var(--line); }

.theme-toggle svg { width: 1.05rem; height: 1.05rem; display: block; }
.theme-toggle .icon-sun { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .icon-sun { display: block; }
  :root:not([data-theme="light"]) .theme-toggle .icon-moon { display: none; }
}

/* footer */

.site-footer {
  margin-top: 4rem;
  padding: 1.5rem 0 2rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.85rem;
}

/* start page */

.home {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 4rem 0;
}

.home .logo-mark { width: 56px; height: auto; margin-bottom: 1.5rem; }

.home h1 {
  margin: 0 0 0.5rem;
  font-size: clamp(2rem, 6vw, 2.75rem);
  font-weight: 600;
  letter-spacing: -0.03em;
}

.home h1 span { font-weight: 400; color: var(--muted); }

.home .tagline {
  margin: 0 0 2.5rem;
  color: var(--muted);
  font-size: 1.1rem;
}

.home-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.75rem;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 1.1rem;
}

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

/* pages */

.page .page-title { margin: 2.5rem 0 1.25rem; }

.page .logo-right {
  float: right;
  width: 64px;
  margin: 0.25rem 0 1rem 1.5rem;
}

/* archive: articles, blog index, tags */

.post-header { margin: 2.5rem 0 2rem; }
.post-title { margin: 0.25rem 0 0; }

.post-meta, .date-label {
  color: var(--muted);
  font-size: 0.9rem;
  margin: 0;
}

.lead { font-size: 1.35rem; font-weight: 600; margin-top: 2.5rem; }

.category-title { margin: 2.5rem 0 0.75rem; color: var(--muted); font-size: 1rem; }

.post-item {
  display: flex;
  align-items: baseline;
  gap: 1.25rem;
  padding: 0.35rem 0;
}

.post-item .date-label { flex: 0 0 4rem; }

.share { margin-top: 2rem; color: var(--muted); font-size: 0.9rem; }

.center { text-align: center; }

/* definition lists */

dl { margin: 0 0 1.2em; }
dt { font-weight: 600; margin-top: 1em; }
dd { margin: 0.2em 0 0; }

/* tables */

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
  display: block;
  overflow-x: auto;
}

th, td {
  text-align: left;
  padding: 0.5rem 0.75rem 0.5rem 0;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

th { font-weight: 600; }

/* quotes */

blockquote {
  margin-left: 0;
  padding-left: 1.25rem;
  border-left: 2px solid var(--fg);
  color: var(--muted);
}

/* code */

code, pre, kbd {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 0.88em;
}

:not(pre) > code {
  background: var(--code-bg);
  padding: 0.1em 0.35em;
  border-radius: 3px;
}

pre {
  background: var(--code-bg);
  padding: 1rem 1.25rem;
  overflow-x: auto;
  line-height: 1.5;
  border-radius: 4px;
}

pre code { background: none; padding: 0; }

div.highlight, figure.highlight { margin: 0 0 1.2em; }
div.highlight pre, figure.highlight pre { margin: 0; }

.highlight .c, .highlight .c1, .highlight .cm, .highlight .cs { color: var(--muted); font-style: italic; }
.highlight .k, .highlight .kn, .highlight .kd, .highlight .ow, .highlight .nb { font-weight: 600; }
.highlight .s, .highlight .s1, .highlight .s2, .highlight .mi { color: var(--muted); }

/* footnotes */

.footnotes {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  font-size: 0.9rem;
}

sup { line-height: 0; }

@media (max-width: 30rem) {
  body { font-size: 1rem; }
  .site-header { padding-top: 1.25rem; }
  .page .logo-right { width: 48px; }
}