/* ==========================================================================
   assets/css/styles.css
   ========================================================================== */

/* Base Variables & Theming */
:root {
  /* Light Mode (Default) */
  --bg-color: #f8fafc;
  --text-color: #0f172a;
  --text-muted: #475569;
  --accent-color: #1d4ed8; /* Trust Blue */
  --accent-hover: #1e3a8a;
  --card-bg: #ffffff;
  --border-color: #e2e8f0;
  --nav-bg: rgba(255, 255, 255, 0.9);
  
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

/* Automatic Dark Mode based on system preference */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #0f172a;
    --text-color: #f8fafc;
    --text-muted: #94a3b8;
    --accent-color: #3b82f6; /* Lighter Trust Blue for dark mode contrast */
    --accent-hover: #60a5fa;
    --card-bg: #1e293b;
    --border-color: #334155;
    --nav-bg: rgba(15, 23, 42, 0.9);
  }
}

/* Reset & Global */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: var(--font-sans); background-color: var(--bg-color);
  color: var(--text-color); line-height: 1.6;
}
a { color: var(--accent-color); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent-hover); }
ul { list-style: none; }
img { max-width: 100%; height: auto; }

/* Typography */
h1, h2, h3 { line-height: 1.2; margin-bottom: 1rem; color: var(--text-color); }
p { margin-bottom: 1rem; color: var(--text-muted); }

/* Layout & Containers */
.container { max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }
.content-section { padding: 4rem 0; }

/* Navigation */
header {
  position: sticky; top: 0; background-color: var(--nav-bg);
  backdrop-filter: blur(8px); border-bottom: 1px solid var(--border-color); z-index: 100;
}
.nav-container { display: flex; justify-content: space-between; align-items: center; padding: 1rem 1.5rem; max-width: 1200px; margin: 0 auto; }
.logo { font-size: 1.5rem; font-weight: 700; color: var(--text-color); }
.nav-links { display: flex; gap: 2rem; align-items: center; }
.nav-links a { font-weight: 500; color: var(--text-muted); }
.nav-links a.active, .nav-links a:hover { color: var(--accent-color); }

/* Buttons */
.btn {
  display: inline-block; padding: 0.75rem 1.5rem; border-radius: 6px;
  font-weight: 600; text-align: center; cursor: pointer; transition: background 0.2s;
}
.btn-primary { background-color: var(--accent-color); color: #ffffff !important; border: none; }
.btn-primary:hover { background-color: var(--accent-hover); }
.btn-outline { background-color: transparent; border: 2px solid var(--accent-color); color: var(--accent-color); }
.btn-outline:hover { background-color: var(--accent-color); color: #ffffff !important; }

/* Grid Layouts */
.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 2rem; }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 2rem; }

/* Cards */
.card { background-color: var(--card-bg); border: 1px solid var(--border-color); border-radius: 8px; padding: 2rem; }

/* Posts Index Layout */
.posts-layout { display: grid; grid-template-columns: 250px 1fr; gap: 3rem; align-items: start; }
.search-input { width: 100%; padding: 0.75rem; border: 1px solid var(--border-color); border-radius: 6px; background: var(--bg-color); color: var(--text-color); margin-bottom: 2rem; }
.post-list { display: flex; flex-direction: column; gap: 1.5rem; }
.tag { display: inline-block; font-size: 0.8rem; padding: 0.2rem 0.6rem; background: var(--border-color); border-radius: 12px; margin-right: 0.5rem; color: var(--text-color); }

/* Individual Post Layout */
.post-container { max-width: 800px; margin: 0 auto; padding: 4rem 1.5rem; }
.post-header { margin-bottom: 3rem; text-align: center; }
.toc-box { background: var(--card-bg); border: 1px solid var(--border-color); padding: 1.5rem; border-radius: 8px; margin-bottom: 3rem; }
.toc-box ul { margin-top: 1rem; padding-left: 1rem; list-style: disc; }
.toc-box li { margin-bottom: 0.5rem; }

/* Footer */
footer { border-top: 1px solid var(--border-color); padding: 2rem 0; text-align: center; margin-top: 4rem; }

/* Hamburger Menu Button (hidden on desktop) */
.nav-toggle {
  display: none;
  background: none; border: none; cursor: pointer; padding: 0.5rem;
  flex-direction: column; gap: 5px; z-index: 200;
}
.nav-toggle span {
  display: block; width: 24px; height: 2.5px; background-color: var(--text-color);
  border-radius: 2px; transition: transform 0.3s, opacity 0.3s;
}
/* Animated X when open */
.nav-toggle.open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* Responsive adjustments */
@media (max-width: 768px) {
  .nav-toggle { display: flex; }

  .nav-links {
    display: none; flex-direction: column; gap: 0;
    position: absolute; top: 100%; left: 0; right: 0;
    background-color: var(--nav-bg); backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 1.5rem; box-shadow: 0 4px 12px rgba(0,0,0,0.08);
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 0.75rem 0; border-bottom: 1px solid var(--border-color); }
  .nav-links a:last-child { border-bottom: none; }
  .nav-links .btn { margin-top: 0.5rem; text-align: center; }

  .posts-layout { grid-template-columns: 1fr; }
  header { position: relative; }
}