*, *::before, *::after {
    box-sizing: border-box;
  }
  
  /* 1. DEFAULT (LIGHT MODE) VARIABLES */
  :root {
      --color-primary: #1F6FA5;
      --color-secondary: #2B88C5;
      --color-accent: #62B6E8;
      --color-current-focus: #0A9F4A;
      --color-heading: #17324A;
      --color-text: #253544; 
      --color-muted: #5F7283;
      --color-background: #F7FAFD; 
      --color-content-bg: #FFFFFF;
      --color-soft-bg: #F1F7FC;
      --color-media-bg: #E6F2FA;
      --color-chip-bg: #EAF4FB;
      --color-border: #D5E5F0;
      --color-light-gray: #EEF6FB;
      
      /* SHADOW FOR LIGHT MODE (Black, soft) */
      --color-shadow: rgba(0, 0, 0, 0.1);
      --button-hover-shadow: 0 6px 16px var(--color-shadow);
      --button-hover-transform: translateY(-1px);
      --button-hover-transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
      
      --font-serif: "Georgia", serif;
      --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
      --font-heading: "Segoe UI Variable Display", "Aptos Display", "Helvetica Neue", Arial, sans-serif;
  }
  
  /* 2. DARK MODE OVERRIDES (Applied via class ONLY) */
  /* We removed the @media block to prevent conflicts with the toggle */
  html.dark {
      --color-primary: #8BCDF2;
      --color-secondary: #66B7EA;
      --color-accent: #B7E3FF;
      --color-current-focus: #86D6A5;
      --color-heading: #EAF4F7;
      --color-text: #DCE5E8; 
      --color-muted: #A9BAC1;
      --color-background: #101820; 
      --color-content-bg: #16222C; 
      --color-soft-bg: #1B2B36;
      --color-media-bg: #1A303F;
      --color-chip-bg: #203746;
      --color-border: #2F4B5E;
      
      /* SHADOW FOR DARK MODE (White, glowing) */
      --color-shadow: rgba(255, 255, 255, 0.1); 
      
      /* Dark mode specific light-gray override for hover effects */
      --color-light-gray: #26363B;
  }

  @media (prefers-reduced-motion: reduce) {
      :root {
          --button-hover-transform: none;
      }
  }
  
  /* Reset and Typography */
  html {
      font-family: var(--font-sans);
      background-color: var(--color-background);
      color: var(--color-text);
      min-height: 100%;
      overflow-y: auto;
      scrollbar-gutter: stable;
      scroll-padding-top: 88px;
  }
  body {
      display: flex;
      flex-direction: column;
      min-height: 100vh;    
      margin: 0;
      padding: 0;
      line-height: 1.6;
  }
  main {
      flex-grow: 1; 
  }

  /* Theme-aware Shiki code highlighting for rendered Markdown. */
  .astro-code {
      background: var(--color-soft-bg) !important;
  }

  .astro-code,
  .astro-code span {
      color: var(--shiki-light);
  }

  html.dark .astro-code,
  html.dark .astro-code span {
      color: var(--shiki-dark);
  }

  [id] {
      scroll-margin-top: 88px;
  }
  h1, h2, h3 {
      font-family: var(--font-heading);
      font-weight: 600;
      color: var(--color-heading);
      line-height: 1.18;
      margin-top: 1.5em;
  }
  
  /* Links */
  a {
      color: var(--color-primary);
      text-decoration: none;
      transition: color 0.3s ease;
  }
  a:hover {
      color: var(--color-secondary); 
      text-decoration: underline;
  }
  
  /* Content Blocks */
  .section-title {
      border-bottom: 2px solid var(--color-light-gray);
      padding-bottom: 5px;
      margin-bottom: 20px;
  }
  .publication, .project {
      margin-bottom: 30px;
      padding: 15px;
      border-left: 4px solid var(--color-primary);
      background: var(--color-content-bg);
      color: var(--color-text);
  }
  
  /* --- HEADER STYLES --- */
  .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background-color: var(--color-background);
      padding: 10px 0;

      /* Uses variable: Black in light mode, White in dark mode */
      box-shadow: 0 4px 12px var(--color-shadow);
  }
  
  /* --- CONTENT BLOCK STYLES --- */
  .content-block {
      margin-bottom: 30px;
      padding: 25px;
      border: 1px solid var(--color-border);
      border-radius: 8px;
      background: var(--color-content-bg); 
      color: var(--color-text); 
      
      /* Uses variable: Black in light mode, White in dark mode */
      box-shadow: 0 4px 8px var(--color-shadow); 
      word-break: break-word;
      overflow-wrap: break-word;
  }
  
  /* --- LAYOUT STYLES --- */
  .profile-container {
      display: grid;
      grid-template-columns: 280px minmax(0, 1fr); 
      gap: 40px; 
      padding-top: 50px; 
  }

  .profile-container > aside {
      position: fixed;
      top: 142px;
      left: max(20px, calc((100vw - 1120px) / 2 + 20px));
      width: 280px;
      align-self: start;
  }

  .profile-container > .home-main {
      grid-column: 2;
  }
  
  @media (max-width: 900px) {
      .profile-container {
          grid-template-columns: 1fr; 
      }

      .profile-container > aside {
          position: static;
          width: auto;
      }

      .profile-container > .home-main {
          grid-column: auto;
      }
  }
  
  .content-wrapper {
      max-width: 1120px;
      width: 100%;
      margin: 0 auto;
      padding: 24px 20px 32px;
      flex-grow: 1; 
  }
  
  footer {
      padding: 20px;
      text-align: center;
      margin-top: auto;
  }