/* ==========================================================================
   Nord Theme for rocket-science.ru
   Based on https://www.nordtheme.com/
   ========================================================================== */

/* --- Nord Palette (CSS Custom Properties) --- */
:root {
  /* Polar Night */
  --nord0: #2E3440;
  --nord1: #3B4252;
  --nord2: #434C5E;
  --nord3: #4C566A;

  /* Snow Storm */
  --nord4: #D8DEE9;
  --nord5: #E5E9F0;
  --nord6: #ECEFF4;

  /* Frost */
  --nord7: #8FBCBB;
  --nord8: #88C0D0;
  --nord9: #81A1C1;
  --nord10: #5E81AC;

  /* Aurora */
  --nord11: #BF616A;
  --nord12: #D08770;
  --nord13: #EBCB8B;
  --nord14: #A3BE8C;
  --nord15: #B48EAD;

  /* Semantic aliases — light mode (default) */
  --bg-primary: #f8f9fb;
  --bg-content: #ffffff;
  --bg-nav: var(--nord0);
  --bg-footer: var(--nord0);
  --bg-code: var(--nord0);
  --bg-inline-code: #e8ecf1;
  --bg-blockquote: var(--nord6);
  --bg-tag: var(--nord5);

  --text-primary: var(--nord0);
  --text-secondary: var(--nord3);
  --text-muted: #6b7994;
  --text-heading: var(--nord0);
  --text-nav: var(--nord4);
  --text-footer: var(--nord4);
  --text-code: var(--nord4);
  --text-inline-code: var(--nord1);

  --accent: var(--nord10);
  --accent-hover: var(--nord9);
  --accent-light: var(--nord8);
  --accent-visited: #4a6f96;
  --border: #dde1e8;
  --border-light: var(--nord5);

  --shadow-card: 0 1px 3px rgba(46, 52, 64, 0.06), 0 1px 2px rgba(46, 52, 64, 0.04);
  --shadow-nav: 0 1px 3px rgba(0, 0, 0, 0.15);
  --table-hover: var(--nord6);
  --pagination-bg: var(--nord5);
  --pagination-disabled-bg: var(--nord6);
  --tag-hover-text: var(--nord6);
  --thead-bg: var(--nord5);

  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'SF Mono', Consolas, monospace;
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  --max-width: 52rem;
  --nav-height: 3.5rem;
  --radius: 6px;
  --radius-lg: 10px;
}

/* --- Dark Mode --- */
[data-theme="dark"] {
  --bg-primary: var(--nord0);
  --bg-content: var(--nord1);
  --bg-nav: #272c36;
  --bg-footer: #272c36;
  --bg-code: #252a33;
  --bg-inline-code: var(--nord2);
  --bg-blockquote: var(--nord1);
  --bg-tag: var(--nord2);

  --text-primary: var(--nord4);
  --text-secondary: #b0b8c8;
  --text-muted: #8994a8;
  --text-heading: var(--nord6);
  --text-nav: var(--nord4);
  --text-footer: var(--nord4);
  --text-code: var(--nord4);
  --text-inline-code: var(--nord8);

  --accent: var(--nord8);
  --accent-hover: var(--nord7);
  --accent-light: var(--nord9);
  --accent-visited: var(--nord9);
  --border: var(--nord2);
  --border-light: var(--nord2);

  --shadow-card: 0 1px 4px rgba(0, 0, 0, 0.2), 0 1px 2px rgba(0, 0, 0, 0.15);
  --shadow-nav: 0 1px 4px rgba(0, 0, 0, 0.3);
  --table-hover: var(--nord2);
  --pagination-bg: var(--nord2);
  --pagination-disabled-bg: var(--nord1);
  --tag-hover-text: var(--nord6);
  --thead-bg: var(--nord2);
}

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

html {
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-weight: 400;
  color: var(--text-primary);
  background-color: var(--bg-primary);
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 650;
  line-height: 1.3;
  color: var(--text-heading);
  margin-top: 1.8em;
  margin-bottom: 0.6em;
}

h1 { font-size: 2rem; letter-spacing: -0.02em; }
h2 { font-size: 1.55rem; letter-spacing: -0.015em; }
h3 { font-size: 1.3rem; }
h4 { font-size: 1.15rem; }
h5 { font-size: 1.05rem; }
h6 { font-size: 1rem; color: var(--text-secondary); }

p {
  margin: 0 0 1.25em;
  font-size: 1rem;
  line-height: 1.75;
}

strong { font-weight: 600; }

small { font-size: 0.85em; }

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2em 0;
}

/* --- Links --- */
a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

a:visited {
  color: var(--accent-visited);
}

/* --- Navigation --- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-nav);
  box-shadow: var(--shadow-nav);
}

.site-nav .nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-height);
}

.site-nav .brand {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--nord6);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.site-nav .brand:hover {
  color: var(--nord8);
  text-decoration: none;
}

.site-nav .nav-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 0.25rem;
}

.site-nav .nav-links li {
  list-style-type: none;
}

.site-nav .nav-links a {
  color: var(--nord4);
  font-size: 0.88rem;
  font-weight: 450;
  padding: 0.4rem 0.75rem;
  border-radius: var(--radius);
  transition: background 0.15s ease, color 0.15s ease;
  text-decoration: none;
}

.site-nav .nav-links a:hover,
.site-nav .nav-links a.active {
  background: var(--nord2);
  color: var(--nord6);
  text-decoration: none;
}

/* Mobile nav toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--nord4);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.25rem;
  line-height: 1;
}

.nav-toggle:hover {
  color: var(--nord8);
}

@media (max-width: 640px) {
  .nav-toggle {
    display: block;
  }

  .site-nav .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--nord1);
    flex-direction: column;
    padding: 0.5rem 1rem 1rem;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  }

  .site-nav .nav-links.open {
    display: flex;
  }

  .site-nav .nav-links a {
    padding: 0.6rem 0.75rem;
    display: block;
  }
}

/* --- Main Content --- */
.site-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

.content-card {
  background: var(--bg-content);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2.5rem;
  box-shadow: var(--shadow-card);
}

@media (max-width: 640px) {
  .content-card {
    padding: 1.5rem 1.25rem;
    border-radius: 0;
  }

  .site-content {
    padding: 1rem 0;
  }
}

/* --- Page Header --- */
.page-header {
  margin-bottom: 2rem;
  padding-bottom: 1.25rem;
  border-bottom: 2px solid var(--border-light);
}

.page-header h1 {
  margin: 0 0 0.3rem;
  font-size: 2rem;
}

.page-header .tagline {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 0;
}

/* --- Post Styling --- */
.post-header {
  margin-bottom: 2rem;
  padding-bottom: 1.25rem;
  border-bottom: 2px solid var(--border-light);
}

.post-header h1 {
  margin: 0 0 0.6rem;
  font-size: 2rem;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 1rem;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.post-meta .date {
  font-weight: 500;
}

.post-meta .separator {
  color: var(--border);
}

/* --- Tags --- */
.tag_box {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.tag_box li {
  list-style-type: none;
  line-height: 1;
}

.tag_box.inline li {
  float: none;
  display: inline-flex;
}

.tag_box a {
  display: inline-block;
  padding: 0.2rem 0.55rem;
  background: var(--bg-tag);
  color: var(--accent);
  border-radius: var(--radius);
  font-size: 0.78rem;
  font-weight: 500;
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease;
  border: 1px solid var(--border-light);
}

.tag_box a:hover {
  background: var(--accent);
  color: var(--tag-hover-text);
  text-decoration: none;
  border-color: var(--accent);
}

.tag_box a span {
  font-size: 0.7em;
  vertical-align: super;
  margin-left: 0.15em;
  opacity: 0.7;
}

.tag_box a.active {
  background: var(--accent);
  color: var(--tag-hover-text);
  border-color: var(--accent);
}

/* --- Blockquotes --- */
blockquote {
  margin: 1.5em 0;
  padding: 1em 1.5em;
  border-left: 4px solid var(--nord8);
  background: var(--bg-blockquote);
  border-radius: 0 var(--radius) var(--radius) 0;
}

blockquote p {
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 0.5em;
  font-size: 0.95rem;
}

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

blockquote small {
  display: block;
  margin-top: 0.5em;
  color: var(--text-muted);
}

blockquote small::before {
  content: "\2014\00A0";
}

/* --- Code --- */
code, kbd, samp {
  font-family: var(--font-mono);
}

code.highlighter-rouge,
code:not([class]),
p code,
li code,
td code {
  background: var(--bg-inline-code);
  color: var(--text-inline-code);
  padding: 0.15em 0.35em;
  border-radius: 4px;
  font-size: 0.85em;
  font-weight: 450;
}

pre {
  margin: 1.5em 0;
  padding: 0;
  background: var(--bg-code);
  border-radius: var(--radius);
  overflow: hidden;
}

pre code {
  display: block;
  padding: 1.25em 1.5em;
  overflow-x: auto;
  font-size: 0.82rem;
  line-height: 1.55;
  color: var(--text-code);
  background: none;
  border: none;
}

div.highlight {
  margin: 1.5em 0;
  border-radius: var(--radius);
  overflow: hidden;
}

div.highlight pre {
  margin: 0;
  border-radius: var(--radius);
}

/* --- Tables --- */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5em 0;
  font-size: 0.92rem;
}

thead th {
  background: var(--thead-bg);
  font-weight: 600;
  text-align: left;
  padding: 0.65em 0.85em;
  border-bottom: 2px solid var(--border);
}

tbody td {
  padding: 0.55em 0.85em;
  border-bottom: 1px solid var(--border-light);
  vertical-align: top;
}

tbody tr:hover {
  background: var(--table-hover);
}

/* --- Lists --- */
ul, ol {
  padding-left: 1.5em;
  margin: 1em 0;
}

li {
  margin-bottom: 0.3em;
  line-height: 1.65;
}

li > ul, li > ol {
  margin-top: 0.3em;
}

/* Disc list override */
ul.disc li {
  list-style-type: disc;
}

/* --- Images --- */
img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
}

.content-card img {
  margin: 1em 0;
}

/* --- Two Column Layout (index page) --- */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin: 1.5em 0;
}

@media (max-width: 640px) {
  .two-col {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
}

.two-col h4 {
  font-variant: small-caps;
  font-size: 1.05rem;
  color: var(--accent);
  margin-top: 0;
  margin-bottom: 0.6em;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 0.3em;
}

.two-col ol {
  padding-left: 1.8em;
}

.two-col ol[type="i"] {
  list-style-type: lower-roman;
}

.two-col ul {
  padding-left: 1.5em;
}

/* --- Posts Table (index page) --- */
.posts-list {
  margin-top: 1.5em;
}

.posts-list table {
  font-size: 0.9rem;
}

.posts-list td:first-child {
  white-space: nowrap;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  width: 7.5rem;
  padding-right: 1.25em;
}

.posts-list td {
  padding: 0.4em 0.6em;
}

.posts-list td a {
  font-weight: 450;
}

/* --- Pagination --- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-light);
}

.pagination .nav-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  background: var(--pagination-bg);
  color: var(--accent);
  text-decoration: none;
  font-size: 1.2rem;
  transition: background 0.15s ease, color 0.15s ease;
}

.pagination .nav-btn:hover {
  background: var(--accent);
  color: var(--tag-hover-text);
  text-decoration: none;
}

.pagination .nav-btn.disabled {
  background: var(--pagination-disabled-bg);
  color: var(--border);
  pointer-events: none;
}

.pagination .nav-btn-archive {
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  padding: 0.5rem 1rem;
  border-radius: 2rem;
  background: var(--pagination-bg);
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 500;
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease;
}

.pagination .nav-btn-archive:hover {
  background: var(--accent);
  color: var(--tag-hover-text);
  text-decoration: none;
}

/* --- Footer --- */
.site-footer {
  background: var(--bg-footer);
  color: var(--text-footer);
  margin-top: 3rem;
}

.site-footer .footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3rem 1.5rem 1.5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

.site-footer h5 {
  color: var(--nord6);
  font-size: 0.95rem;
  font-weight: 600;
  margin: 0 0 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.site-footer p {
  color: var(--nord4);
  font-size: 0.88rem;
  line-height: 1.7;
  margin: 0 0 0.5em;
}

.site-footer ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.site-footer li {
  margin-bottom: 0.35rem;
}

.site-footer a {
  color: var(--nord8);
  font-size: 0.88rem;
  text-decoration: none;
  transition: color 0.15s ease;
}

.site-footer a:hover {
  color: var(--nord7);
  text-decoration: underline;
}

.footer-bottom {
  border-top: 1px solid var(--nord2);
  padding-top: 1.25rem;
  text-align: center;
  font-size: 0.78rem;
  color: var(--nord3);
}

.footer-bottom a {
  color: var(--nord4);
}

.footer-bottom a:hover {
  color: var(--nord8);
}

.footer-bottom code {
  color: var(--nord3);
  background: none;
  padding: 0;
  font-size: inherit;
}

/* --- Smallcaps --- */
.smallcaps {
  font-variant: small-caps;
}

/* --- Archive / Categories page --- */
.archive-year {
  color: var(--accent);
  border-bottom: 2px solid var(--border-light);
  padding-bottom: 0.3em;
}

.archive-month {
  color: var(--text-secondary);
}

/* --- Theme Toggle --- */
.theme-toggle {
  background: none;
  border: 1px solid var(--nord3);
  color: var(--nord4);
  cursor: pointer;
  padding: 0.3rem 0.55rem;
  border-radius: var(--radius);
  font-size: 1rem;
  line-height: 1;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-left: 0.5rem;
}

.theme-toggle:hover {
  background: var(--nord2);
  color: var(--nord6);
  border-color: var(--nord2);
}

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  display: none;
}

[data-theme="dark"] .theme-toggle .icon-sun {
  display: inline;
}

[data-theme="light"] .theme-toggle .icon-moon {
  display: inline;
}

/* --- Utilities --- */
.text-muted { color: var(--text-muted); }
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* --- Print --- */
@media print {
  .site-nav,
  .site-footer,
  .pagination {
    display: none;
  }

  body {
    background: #fff;
    color: #000;
  }

  .content-card {
    box-shadow: none;
    padding: 0;
  }

  a { color: #000; text-decoration: underline; }
  a[href]::after { content: " (" attr(href) ")"; font-size: 0.8em; }
}