:root {
    --bg:        #f5f0e8;
    --paper:     #fdfaf4;
    --ink:       #2c2416;
    --ink-light: #7a6a52;
    --accent:    #4a7c59;
    --accent-2:  #c8a96e;
    --border:    #e0d8c8;
    --card-bg:   #ffffff;
  }

  * { margin: 0; padding: 0; box-sizing: border-box; }

  body {
    font-family: 'Lora', Georgia, serif;
    background: var(--bg);
    color: var(--ink);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
  }

  /* subtle grain overlay */
  body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.04'/%3E%3C/svg%3E");
    pointer-events: none;
    z-index: 0;
  }

  /*  HEADER  */
  header {
    padding: 28px 40px;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--paper);
    position: relative;
    z-index: 1;
  }

  .logo-leaf {
    font-size: 22px;
  }

  .logo-text {
    font-family: 'Lora', serif;
    font-size: 20px;
    font-weight: 600;
    color: var(--accent);
    letter-spacing: -0.3px;
  }

  .logo-sub {
    font-family: 'DM Mono', monospace;
    font-size: 10px;
    font-weight: 300;
    color: var(--ink-light);
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-left: 2px;
  }

  /*  MAIN  */
  main {
    flex: 1;
    max-width: 780px;
    width: 100%;
    margin: 0 auto;
    padding: 48px 24px 80px;
    position: relative;
    z-index: 1;
  }

  .intro {
    margin-bottom: 40px;
  }

  .intro h1 {
    font-size: 32px;
    font-weight: 600;
    color: var(--ink);
    line-height: 1.25;
    margin-bottom: 10px;
  }

  .intro h1 em {
    color: var(--accent);
    font-style: italic;
  }

  .intro p {
    font-size: 15px;
    color: var(--ink-light);
    line-height: 1.7;
  }

  /*  LESSONS GRID  */
  .section-label {
    font-family: 'DM Mono', monospace;
    font-size: 10px;
    font-weight: 400;
    letter-spacing: 2.5px;
    text-transform: uppercase;
    color: var(--ink-light);
    margin-bottom: 16px;
  }

  .lessons-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 14px;
    margin-bottom: 48px;
  }

  .lesson-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 20px 22px;
    cursor: pointer;
    transition: border-color 0.2s, transform 0.15s, box-shadow 0.2s;
    position: relative;
    overflow: hidden;
  }

  .lesson-card::before {
    content: '';
    position: absolute;
    left: 0; top: 0; bottom: 0;
    width: 3px;
    background: var(--accent);
    transform: scaleY(0);
    transition: transform 0.2s;
    transform-origin: bottom;
  }

  .lesson-card:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(74,124,89,0.1);
  }

  .lesson-card:hover::before { transform: scaleY(1); }

  .lesson-card.active {
    border-color: var(--accent);
    background: #f0f7f2;
  }

  .lesson-card.active::before { transform: scaleY(1); }

  .lesson-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--ink);
    margin-bottom: 4px;
  }

  .lesson-meta {
    font-family: 'DM Mono', monospace;
    font-size: 10px;
    color: var(--ink-light);
    letter-spacing: 0.5px;
  }

  /*  PRACTICE AREA  */
  .practice-area {
    background: var(--paper);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 36px 40px;
    display: none;
    animation: fadeIn 0.3s ease;
  }

  .practice-area.visible { display: block; }

  @keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to   { opacity: 1; transform: translateY(0); }
  }

  .practice-label {
    font-family: 'DM Mono', monospace;
    font-size: 10px;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 28px;
  }

  .word-display {
    text-align: center;
    margin-bottom: 32px;
  }

  .word-original {
    font-size: 48px;
    font-weight: 600;
    color: var(--ink);
    line-height: 1.1;
    margin-bottom: 6px;
    letter-spacing: -1px;
  }

  .word-hint {
    font-family: 'DM Mono', monospace;
    font-size: 11px;
    color: var(--ink-light);
    letter-spacing: 1px;
  }

  .word-translation {
    font-size: 28px;
    font-style: italic;
    color: var(--accent);
    margin-top: 20px;
    min-height: 40px;
    transition: opacity 0.3s;
  }

  .word-translation.hidden { opacity: 0; }

  .btn-row {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin-top: 28px;
  }

  button {
    font-family: 'Lora', serif;
    font-size: 14px;
    padding: 11px 28px;
    border-radius: 3px;
    border: 1px solid var(--border);
    cursor: pointer;
    transition: all 0.15s;
  }

  .btn-primary {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
    font-weight: 600;
  }

  .btn-primary:hover {
    background: #3d6b4c;
    border-color: #3d6b4c;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(74,124,89,0.25);
  }

  .btn-secondary {
    background: transparent;
    color: var(--ink-light);
  }

  .btn-secondary:hover {
    background: var(--border);
    color: var(--ink);
  }

  /*  WORD LIST  */
  .word-list {
    margin-top: 32px;
    border-top: 1px solid var(--border);
    padding-top: 24px;
  }

  .word-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px dashed var(--border);
    font-size: 14px;
    animation: fadeIn 0.2s ease both;
  }

  .word-row:last-child { border-bottom: none; }

  .word-row .w-nl { font-weight: 600; color: var(--ink); }
  .word-row .w-en { color: var(--ink-light); font-style: italic; }

  /*  STATUS  */
  #status {
    font-family: 'DM Mono', monospace;
    font-size: 11px;
    color: var(--ink-light);
    text-align: center;
    margin-top: 16px;
    min-height: 18px;
  }

  /*  LOADING  */
  .loading-dots::after {
    content: '...';
    animation: dots 1s steps(3, end) infinite;
  }

  @keyframes dots {
    0%   { content: '.'; }
    33%  { content: '..'; }
    66%  { content: '...'; }
  }