/* ------- Base / Theme ------- */
:root {
  --bg: #ffffff;
  --bg-alt: #f7f7f9;
  --text: #1f2937;
  --muted: #6b7280;
  --accent: #2563eb;
  --border: #e5e7eb;
  --code-bg: #0b1020;
  --code-text: #e5e7eb;
  --callout-info: #e0f2fe;
  --callout-note: #f5f3ff;
  --callout-success: #ecfdf5;
  --callout-warn: #fff7ed;
}
:root[data-theme="dark"] {
  --bg: #0b0e14;
  --bg-alt: #0f1320;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --accent: #60a5fa;
  --border: #1f2937;
  --code-bg: #0b1020;
  --code-text: #f3f4f6;
  --callout-info: #07293f;
  --callout-note: #1c1733;
  --callout-success: #0f2a20;
  --callout-warn: #2e2414;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font: 16px/1.65 system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif;
  color: var(--text);
  background: var(--bg);
}

/* ------- Layout ------- */
.container { max-width: 1120px; margin: 0 auto; padding: 0 1rem; }
.site-header {
  position: sticky; top: 0; z-index: 20;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.site-header .brand {
  display: flex; align-items: center; gap: .75rem; padding: .75rem 0;
}
.site-title { font-weight: 700; letter-spacing: .3px; }
.site-nav { display: flex; gap: 1rem; }
.site-nav a { color: var(--muted); text-decoration: none; padding: .75rem 0; }
.site-nav a:hover { color: var(--text); }

.theme-toggle {
  border: 1px solid var(--border);
  background: var(--bg-alt);
  padding: .35rem .55rem;
  border-radius: .5rem;
  cursor: pointer;
}

.layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 2rem;
  max-width: 1120px;
  margin: 2rem auto;
  padding: 0 1rem;
}
@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; }
  .toc { position: static; order: -1; }
}

.toc {
  position: sticky; top: 5.5rem; align-self: start;
  border: 1px solid var(--border);
  background: var(--bg-alt);
  border-radius: 12px;
  padding: 1rem;
  max-height: calc(100vh - 7rem);
  overflow: auto;
}
.toc__title { margin: 0 0 .75rem; font-size: 1rem; }
#tocList { display: flex; flex-direction: column; gap: .25rem; }
#tocList a {
  text-decoration: none;
  color: var(--muted);
  border-radius: 8px;
  padding: .25rem .5rem;
}
#tocList a:hover { background: var(--bg); color: var(--text); }
#tocList .active { background: var(--bg); color: var(--accent); }
.toc--h2 { margin-left: 0; font-weight: 600; }
.toc--h3 { margin-left: 1rem; font-size: .95rem; }

.post { min-width: 0; }
.post__header h1 {
  margin: 0 0 .25rem;
  font-size: clamp(1.8rem, 2.5vw + 1rem, 2.6rem);
  line-height: 1.2;
}
.post__meta {
  margin: 0 0 1rem;
  color: var(--muted);
}
.post__meta .sep { margin: 0 .5rem; color: var(--border); }

.hero { margin: 1rem 0 0; }
.hero img { width: 100%; border-radius: 14px; }
.hero figcaption { color: var(--muted); font-size: .9rem; margin-top: .5rem; }

.post h2 {
  margin-top: 2.2rem;
  font-size: clamp(1.35rem, 1.2vw + 1rem, 1.7rem);
  border-bottom: 1px solid var(--border);
  padding-bottom: .25rem;
}
.post h3 { margin-top: 1.4rem; font-size: 1.125rem; }
.post p { margin: .65rem 0; }
.post ul, .post ol { padding-left: 1.2rem; }
.post li { margin: .25rem 0; }

/* Anchor icon on headings */
.anchor {
  margin-left: .4rem;
  text-decoration: none;
  color: var(--muted);
  opacity: .6;
}
.anchor:hover { opacity: 1; color: var(--accent); }

/* Callouts */
.callout {
  border-radius: 12px;
  padding: .85rem 1rem;
  margin: 1rem 0;
  border: 1px solid var(--border);
}
.callout.info { background: var(--callout-info); }
.callout.note { background: var(--callout-note); }
.callout.success { background: var(--callout-success); }
.callout.warn { background: var(--callout-warn); }

/* Figures */
figure { margin: 1rem 0; }
figure img { width: 100%; border-radius: 12px; }
figcaption { color: var(--muted); font-size: .9rem; margin-top: .35rem; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
@media (max-width: 700px) { .grid-2 { grid-template-columns: 1fr; } }

/* Code blocks (if you include any) */
pre, code, kbd, samp {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}
pre {
  background: var(--code-bg);
  color: var(--code-text);
  padding: 1rem;
  border-radius: 12px;
  overflow: auto;
  border: 1px solid var(--border);
}

/* References */
.refs { padding-left: 1.2rem; }
.refs li { margin: .35rem 0; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 3rem;
  background: var(--bg);
}
.site-footer .container { padding: 1rem; color: var(--muted); }

/* A11y */
.skip-link {
  position: absolute; left: -9999px; top: auto; width: 1px; height: 1px; overflow: hidden;
}
.skip-link:focus {
  position: static; width: auto; height: auto; padding: .5rem; background: var(--accent); color: #fff;
}

/* Print styles */
@media print {
  :root { --bg: #fff; --text: #000; }
  .site-header, .site-footer, .toc, .theme-toggle, .site-nav, .anchor { display: none !important; }
  .layout { display: block; margin: 0; padding: 0; }
  .post h2 { border: none; }
  a { color: inherit; text-decoration: none; }
}
/* ============================================= */
/* BASE IMAGE STYLES - APPLIES TO ALL IMAGES */
/* ============================================= */

/* Target all images in main content, figure elements, and those with .responsive class */
main img,
.figure img,
img.responsive {
  display: block;            /* Treat images as block elements */
  max-width: 55%;            /* Never wider than 90% of container */
  width: auto;               /* Maintain original width ratio */
  height: auto;              /* Maintain original height ratio */
  margin: 0 auto;            /* Center horizontally */
  object-fit: contain;       /* Show entire image without cropping */
  border-radius: 8px;        /* Slightly rounded corners */
  box-shadow: 0 2px 8px rgba(0,0,0,0.1); /* Subtle shadow */
}

/* ============================================= */
/* FIGURE STYLES (for images with captions) */
/* ============================================= */

.figure {
  margin: 9px 0;            /* Space above/below figure */
  text-align: center;        /* Center all figure content */
}

.figure img {
  max-width: 100%;            /* Limits image to 85% of container width */
  max-height: 500px;         /* Absolute height limit (from .img-limit-lg) */
  border-radius: 8px;        /* Rounded corners */
  box-shadow: 0 2px 8px rgba(0,0,0,0.1); /* Subtle shadow */
  display: block;            /* Treats image as block element */
  margin: 0 auto;           /* Centers image horizontally */
}

.figure figcaption {
  color: #666;               /* Gray caption text */
  font-size: 14px;           /* Slightly smaller text */
  margin-top: 8px;           /* Space between image and caption */
  padding: 0 10%;            /* Padding to prevent long captions from stretching */
}

/* ============================================= */
/* IMAGE SIZE LIMIT CLASSES (apply as needed) */
/* ============================================= */

/* Medium size limit - for moderately large images */
.img-limit-md img,
img.img-limit-md {
  max-width: 100%;            /* 80% of container width */
  max-height: 500px;         /* Hard pixel limit */
}

/* Large size limit - for bigger images */
.img-limit-lg img,
img.img-limit-lg {
  max-width: 100%;            /* 85% of container width */
  max-height: 600px;         /* Hard pixel limit */
}

/* Extra large size limit - for very big images */
.img-limit-xl img,
img.img-limit-xl {
  max-width: 90%;            /* 90% of container width */
  max-height: 600px;         /* Hard pixel limit */
}

/* ============================================= */
/* GALLERY STYLES (for multiple images side-by-side) */
/* ============================================= */

.gallery-2,
.gallery-3 {
  display: grid;             /* Use CSS Grid for layout */
  gap: 10px;                /* Space between images */
  margin: 20px 0;           /* Space above/below gallery */
}

.gallery-2 {
  grid-template-columns: repeat(2, 1fr); /* Two equal columns */
}

.gallery-3 {
  grid-template-columns: repeat(3, 1fr); /* Three equal columns */
}

/* Gallery images should be smaller than standalone images */
.gallery-2 img,
.gallery-3 img {
  max-width: 100%;          /* Fill available column space */
  max-height: 300px;        /* Fixed height for consistency */
}

/* ============================================= */
/* RESPONSIVE ADJUSTMENTS (for different screen sizes) */
/* ============================================= */

/* For tablets and smaller desktops */
@media (max-width: 1024px) {
  .img-limit-xl img,
  img.img-limit-xl {
    max-height: 400px;       /* Reduce extra large images */
  }
}

/* For mobile devices */
@media (max-width: 768px) {
  /* Make all images smaller on mobile */
  main img,
  .figure img,
  img.responsive {
    max-width: 90%;          /* Slightly wider on small screens */
    max-height: 350px;       /* Reduced height */
  }
  
  /* Stack gallery images on mobile */
  .gallery-2,
  .gallery-3 {
    grid-template-columns: 1fr; /* Single column layout */
  }
  
  /* Allow gallery images to be slightly taller on mobile */
  .gallery-2 img,
  .gallery-3 img {
    max-height: 250px;
  }
}

/* For very small mobile devices */
@media (max-width: 480px) {
  main img,
  .figure img,
  img.responsive {
    max-height: 300px;       /* Even smaller on tiny screens */
  }
  
  .figure figcaption {
    font-size: 12px;         /* Smaller caption text */
  }
}

/* ============================================= */
/* SAFETY CATCH-ALL FOR ANY IMAGE */
/* ============================================= */

img {
  max-width: 90%;           /* Never overflow container */
  height: auto;              /* Maintain aspect ratio */
}