/*
Theme Name: Khue Tech
Theme URI: https://khuetran.com
Author: Khuê Trần
Description: Minimal tech-blog theme — system fonts, dark-mode auto, JSON-LD schema baked in, OG/Twitter meta auto, no jQuery, mobile-first. Built for fast reading on AI/tech long-form posts.
Version: 1.0.0
License: GPL-2.0-or-later
Tags: blog, minimalist, dark-mode, two-columns, custom-colors, custom-menu, featured-images, threaded-comments
Text Domain: khue-tech
*/

/* ============ CSS RESET ============ */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body { margin: 0; }
img, video { max-width: 100%; height: auto; display: block; }

/* ============ TOKENS ============ */
:root {
  --max-w: 720px;
  --max-w-wide: 980px;
  --c-bg: #fdfdfc;
  --c-surface: #ffffff;
  --c-text: #1a1a1a;
  --c-text-soft: #555555;
  --c-text-faint: #888888;
  --c-link: #0958d9;
  --c-link-hover: #003a8c;
  --c-border: #e8e6e1;
  --c-accent: #06b6d4;
  --c-code-bg: #f6f5f1;
  --c-code-text: #2c2c2c;
  --c-pre-bg: #1e1f2b;
  --c-pre-text: #e6e6e6;
  --c-quote-bar: #06b6d4;
  --c-quote-bg: #f6f5f1;
  --c-tag-bg: #f0eee9;
  --c-tag-text: #444;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Inter", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-serif: ui-serif, Charter, Georgia, Cambria, "Times New Roman", serif;
  --font-mono: ui-monospace, "SF Mono", "JetBrains Mono", "Fira Code", Menlo, Consolas, "Liberation Mono", monospace;
  --radius: 6px;
  --line: 1.7;
}

@media (prefers-color-scheme: dark) {
  :root {
    --c-bg: #0e1014;
    --c-surface: #161922;
    --c-text: #e6e6e6;
    --c-text-soft: #a3a3a3;
    --c-text-faint: #6e6e6e;
    --c-link: #6cb4ff;
    --c-link-hover: #93c8ff;
    --c-border: #262936;
    --c-code-bg: #1a1d28;
    --c-code-text: #d6d6d6;
    --c-pre-bg: #0a0c12;
    --c-pre-text: #e6e6e6;
    --c-quote-bg: #161922;
    --c-tag-bg: #1f222e;
    --c-tag-text: #c0c0c0;
  }
}

/* ============ BASE ============ */
body {
  background: var(--c-bg);
  color: var(--c-text);
  font-family: var(--font-sans);
  font-size: 18px;
  line-height: var(--line);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: "kern" 1, "liga" 1;
  text-rendering: optimizeLegibility;
}

a {
  color: var(--c-link);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color .15s ease;
}
a:hover, a:focus { color: var(--c-link-hover); }

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -.015em;
  margin: 2em 0 .6em;
  color: var(--c-text);
}
h1 { font-size: 2rem; margin-top: 0; }
h2 { font-size: 1.55rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.1rem; }

p, ul, ol, blockquote, pre, table, figure { margin: 0 0 1.15em; }

ul, ol { padding-left: 1.5em; }
li { margin-bottom: .3em; }
li > p { margin-bottom: .4em; }

hr {
  border: 0;
  border-top: 1px solid var(--c-border);
  margin: 2.5em auto;
  max-width: 120px;
}

blockquote {
  border-left: 3px solid var(--c-quote-bar);
  background: var(--c-quote-bg);
  margin: 1.4em 0;
  padding: .8em 1.2em;
  color: var(--c-text-soft);
  border-radius: 0 var(--radius) var(--radius) 0;
}
blockquote p:last-child { margin-bottom: 0; }

code, kbd, samp {
  font-family: var(--font-mono);
  font-size: .88em;
  background: var(--c-code-bg);
  color: var(--c-code-text);
  padding: .15em .4em;
  border-radius: 4px;
  word-wrap: break-word;
}

pre {
  background: var(--c-pre-bg);
  color: var(--c-pre-text);
  padding: 1em 1.2em;
  border-radius: var(--radius);
  overflow-x: auto;
  font-size: .85em;
  line-height: 1.55;
  -webkit-overflow-scrolling: touch;
}
pre code {
  background: transparent;
  color: inherit;
  padding: 0;
  font-size: inherit;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: .92em;
  display: block;
  overflow-x: auto;
  white-space: nowrap;
}
@media (min-width: 720px) {
  table { display: table; white-space: normal; }
}
th, td { padding: .55em .8em; border-bottom: 1px solid var(--c-border); text-align: left; }
th { font-weight: 700; background: var(--c-code-bg); }

video {
  margin: 1.4em auto;
  border-radius: var(--radius);
  background: #000;
}

img { border-radius: var(--radius); }

/* ============ LAYOUT ============ */
.site-header {
  border-bottom: 1px solid var(--c-border);
  padding: 1em 1.2em;
  position: sticky;
  top: 0;
  background: color-mix(in srgb, var(--c-bg) 92%, transparent);
  backdrop-filter: saturate(180%) blur(8px);
  -webkit-backdrop-filter: saturate(180%) blur(8px);
  z-index: 100;
}
.site-header-inner {
  max-width: var(--max-w-wide);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5em;
}
.site-title {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -.01em;
}
.site-title a {
  color: var(--c-text);
  text-decoration: none;
}
.site-title a:hover { color: var(--c-accent); }
.site-tagline {
  color: var(--c-text-faint);
  font-size: .85rem;
  margin-left: .5em;
}

.site-nav { display: flex; gap: 1.2em; flex-wrap: wrap; }
.site-nav a {
  color: var(--c-text-soft);
  text-decoration: none;
  font-size: .92rem;
  font-weight: 500;
}
.site-nav a:hover { color: var(--c-link); }

.site-content {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2.5em 1.2em 4em;
}

.site-footer {
  border-top: 1px solid var(--c-border);
  padding: 2em 1.2em;
  color: var(--c-text-faint);
  font-size: .88rem;
  text-align: center;
}
.site-footer a { color: var(--c-text-soft); }

/* ============ ARCHIVE ============ */
.post-list { list-style: none; padding: 0; margin: 0; }
.post-list-item {
  padding: 1.6em 0;
  border-bottom: 1px solid var(--c-border);
}
.post-list-item:last-child { border-bottom: 0; }
.post-list-meta {
  font-size: .85rem;
  color: var(--c-text-faint);
  margin-bottom: .3em;
  display: flex;
  gap: 1em;
  flex-wrap: wrap;
}
.post-list-title {
  margin: 0 0 .3em;
  font-size: 1.4rem;
  line-height: 1.3;
}
.post-list-title a {
  color: var(--c-text);
  text-decoration: none;
}
.post-list-title a:hover { color: var(--c-link); }
.post-list-excerpt {
  color: var(--c-text-soft);
  font-size: .96rem;
  line-height: 1.55;
  margin: .4em 0 .2em;
}

.archive-title {
  font-size: 1.5rem;
  margin: 0 0 .3em;
  color: var(--c-text-soft);
}
.archive-title span { color: var(--c-text); }

/* ============ SINGLE POST ============ */
.post-header { margin-bottom: 2em; }
.post-title {
  font-size: clamp(1.75rem, 1.4rem + 1.5vw, 2.4rem);
  line-height: 1.18;
  margin: 0 0 .5em;
  letter-spacing: -.02em;
}
.post-meta {
  color: var(--c-text-faint);
  font-size: .9rem;
  display: flex;
  gap: 1em;
  flex-wrap: wrap;
  align-items: center;
}
.post-meta a { color: var(--c-text-soft); text-decoration: none; }
.post-meta a:hover { color: var(--c-link); }

.post-content { font-size: 1.05rem; }
.post-content > *:first-child { margin-top: 0; }
.post-content figure { margin: 1.5em 0; }
.post-content figcaption {
  font-size: .85rem;
  color: var(--c-text-faint);
  text-align: center;
  margin-top: .5em;
}

.post-footer {
  margin-top: 3em;
  padding-top: 1.5em;
  border-top: 1px solid var(--c-border);
  display: flex;
  flex-wrap: wrap;
  gap: 1em;
  justify-content: space-between;
  align-items: center;
  font-size: .9rem;
  color: var(--c-text-soft);
}

.tag-list { display: flex; flex-wrap: wrap; gap: .4em; }
.tag-chip {
  background: var(--c-tag-bg);
  color: var(--c-tag-text);
  padding: .25em .65em;
  border-radius: 999px;
  font-size: .8rem;
  text-decoration: none;
}
.tag-chip:hover { background: var(--c-accent); color: #fff; }

/* ============ PAGINATION ============ */
.pagination {
  display: flex;
  gap: .6em;
  justify-content: center;
  margin: 2.5em 0;
  flex-wrap: wrap;
}
.pagination .page-numbers {
  padding: .4em .8em;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  color: var(--c-text-soft);
  text-decoration: none;
  font-size: .9rem;
}
.pagination .page-numbers.current {
  background: var(--c-text);
  color: var(--c-bg);
  border-color: var(--c-text);
}
.pagination .page-numbers:hover:not(.current) {
  border-color: var(--c-link);
  color: var(--c-link);
}

/* ============ COMMENTS ============ */
.comments-section { margin-top: 3em; }
.comments-title { font-size: 1.2rem; margin-bottom: 1em; }
.comment-list { list-style: none; padding: 0; }
.comment { padding: 1em 0; border-bottom: 1px solid var(--c-border); }
.comment-author { font-weight: 600; font-size: .95rem; }
.comment-meta { font-size: .82rem; color: var(--c-text-faint); margin-bottom: .5em; }
.comment-form input[type="text"],
.comment-form input[type="email"],
.comment-form input[type="url"],
.comment-form textarea {
  width: 100%;
  padding: .55em .7em;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  background: var(--c-surface);
  color: var(--c-text);
  font: inherit;
  margin-top: .25em;
}
.comment-form label { display: block; margin: .8em 0 .2em; font-size: .9rem; color: var(--c-text-soft); }
.comment-form .submit, .comment-form input[type="submit"] {
  background: var(--c-text);
  color: var(--c-bg);
  border: 0;
  padding: .6em 1.4em;
  border-radius: var(--radius);
  cursor: pointer;
  font: inherit;
  margin-top: 1em;
}

/* ============ SEARCH FORM ============ */
.search-form {
  display: flex;
  gap: .5em;
  margin: 1em 0;
}
.search-form input[type="search"] {
  flex: 1;
  padding: .55em .8em;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  background: var(--c-surface);
  color: var(--c-text);
  font: inherit;
}
.search-form button {
  background: var(--c-text);
  color: var(--c-bg);
  border: 0;
  padding: .55em 1.2em;
  border-radius: var(--radius);
  cursor: pointer;
  font: inherit;
}

/* ============ UTIL ============ */
.screen-reader-text {
  position: absolute;
  width: 1px; height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.alignleft { float: left; margin: .4em 1.2em 1em 0; }
.alignright { float: right; margin: .4em 0 1em 1.2em; }
.aligncenter { display: block; margin-left: auto; margin-right: auto; }
.wp-caption { max-width: 100%; }
.wp-caption-text {
  font-size: .85rem;
  color: var(--c-text-faint);
  text-align: center;
  margin-top: .4em;
}

/* ============ MOBILE TWEAKS ============ */
@media (max-width: 640px) {
  body { font-size: 17px; }
  .site-content { padding: 1.8em 1.1em 3em; }
  .site-header-inner { gap: .8em; }
  .site-tagline { display: none; }
  h1 { font-size: 1.6rem; }
  h2 { font-size: 1.3rem; }
  .post-title { font-size: 1.65rem; }
  pre { font-size: .8em; padding: .8em 1em; }
}

/* ============ PRINT ============ */
@media print {
  .site-header, .site-footer, .comments-section, .post-footer { display: none; }
  body { font-size: 12pt; color: #000; background: #fff; }
  a { color: #000; text-decoration: underline; }
  pre, code { border: 1px solid #ccc; }
}