/* 
  :root is the top-level selector; we declare CSS variables here for easy theming.
*/
:root {
    /* A fluid spacing scale you can reuse across components. */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
  
    /* Max width of the widget for nice readable lines. */
    --content-max: 720px;
  
    /* Typography: a system font stack for good defaults. */
    --font-sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue",
                 Arial, "Noto Sans", "Liberation Sans", sans-serif;
  
    /* Light theme colors (default). */
    --bg: #ffffff;
    --fg: #0f172a;     /* deep slate text */
    --muted: #475569;  /* subtler text */
    --primary: #000000;/* blue for focus/brand */
    --card: #f1f5f9;   /* soft panel background */
    --ring: #93c5fd;   /* outline glow color */
    --tg: #ffffff;
  }
  
  /* Respect OS-level dark mode automatically. */
  @media (prefers-color-scheme: dark) {
    :root {
      --bg: #161414;
      --fg: #e5e7eb;
      --muted: #9aa4b2;
      --primary: #ffffff;
      --card: #222325;
      --ring: #ffffff;
      --tg: #000000;
    }
  }
  
  /* Reset margins and set base font across page. */
  * { box-sizing: border-box; }
  html, body { height: 100%; }
  
  body {
    margin: 0;                     /* Remove default margin. */
    font-family: var(--font-sans); /* Use our font stack. */
    color: var(--fg);              /* Default text color. */
    background: radial-gradient(   /* A light radial background for subtle depth. */
      circle at 20% 10%,
      rgba(99, 102, 241, 0.08),
      transparent 30%
    ), var(--bg);
    line-height: 1.6;              /* Comfortable reading. */
    display: grid;                 /* Center content vertically/horizontally. */
    place-items: center;
    padding: var(--space-8);
  }
  
  /* Constrain main content width and center it. */
  main {
    width: 100%;
    max-width: var(--content-max);
  }
  
  /* The widget card container. */
  .quote-widget {
    background: var(--card);
    border: 1px solid rgba(148, 163, 184, 0.2);   /* subtle border */
    border-radius: 16px;                           /* rounded corners */
    padding: var(--space-8);
    box-shadow: 0 10px 30px rgba(2, 6, 23, 0.25);  /* soft shadow */
  }
  
  /* Title style. */
  .title {
    margin: 0 0 var(--space-6) 0;
    font-size: clamp(1.25rem, 2.5vw, 1.75rem); /* Responsive font sizing. */
    letter-spacing: 0.3px;
  }
  
  /* Layout the quote area. */
  .quote-box {
    margin: 0 0 var(--space-6) 0;
  }
  
  /* The quoted text itself. */
  #quote {
    margin: 0;
    font-size: clamp(1.125rem, 2.2vw, 1.5rem);
    font-weight: 600;
  }
  
  /* The author line styling. */
  #author {
    margin-top: var(--space-3);
    color: var(--muted);
    font-style: italic;
  }
  
  /* Control buttons row. */
  .controls {
    display: flex;
    gap: var(--space-3);     /* space between buttons */
    flex-wrap: wrap;         /* wrap on small screens */
  }
  
  /* Base button styling. */
  button {
    appearance: none;                /* normalize across browsers */
    border: 1px solid transparent;   /* border for focus/hover transitions */
    border-radius: 10px;
    padding: var(--space-3) var(--space-6);
    font: inherit;                   /* inherit font settings from body */
    cursor: pointer;
    background: var(--primary);
    color: var(--tg);
    transition: transform 120ms ease, box-shadow 120ms ease, border-color 120ms ease;
  }
  
  /* Hover gives a subtle lift. */
  button:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 16px rgba(2, 6, 23, 0.25);
  }
  
  /* Keyboard focus ring for accessibility. */
  button:focus-visible {
    outline: none;
    border-color: var(--ring);
    box-shadow: 0 0 0 4px rgba(147, 197, 253, 0.35);
  }
  
  /* Secondary-looking button style using a data attribute if needed later.
     (Not used now, but shows how to theme variants.) */
  button[data-variant="secondary"] {
    background: transparent;
    color: var(--fg);
    border-color: rgba(148,163,184,0.4);
  }
  
  /* Fade animation class we toggle in JS. */
  .fade {
    animation: fadeIn 280ms ease;
  }
  
  /* Keyframes define opacity transition for .fade. */
  @keyframes fadeIn {
    from { opacity: 0; transform: translateY(2px); }
    to   { opacity: 1; transform: translateY(0);    }
  }
  
  #copy-quote {
    display: flex;                /* center the icon */
    align-items: center;
    justify-content: center;
    padding: var(--space-3);       /* smaller padding for icon */
    width: 40px;                   /* make it square */
    height: 40px;
  }
  
  #copy-quote svg {
    pointer-events: none;          /* clicks go to button, not SVG */
  }