/* ============================================================
     LANDING SCREEN
     ============================================================ */
  .landing-main {
    flex: 1;
    padding: 16px var(--pad-x) max(28px, env(safe-area-inset-bottom));
    display: flex;
    flex-direction: column;
    gap: 24px;
    position: relative;
    overflow: hidden;
  }
  #screen-progress > .landing-main > *,
  #screen-settings > .landing-main > * {
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    width: 100%;
  }

  /* Floating decorative orbs in the background */
  .landing-main::before,
  .landing-main::after {
    content: "";
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.55;
    pointer-events: none;
    z-index: -1;
  }
  .landing-main::before {
    width: 380px; height: 380px;
    left: -120px;
    top: 60px;
    background: radial-gradient(circle, rgba(56,189,248,0.55), transparent 70%);
    animation: orbDriftA 18s ease-in-out infinite;
  }
  .landing-main::after {
    width: 460px; height: 460px;
    right: -160px;
    top: 200px;
    background: radial-gradient(circle, rgba(129,140,248,0.50), transparent 70%);
    animation: orbDriftB 22s ease-in-out infinite;
  }
  @keyframes orbDriftA {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33%      { transform: translate(80px, 60px) scale(1.1); }
    66%      { transform: translate(140px, -40px) scale(0.95); }
  }
  @keyframes orbDriftB {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33%      { transform: translate(-100px, 80px) scale(1.08); }
    66%      { transform: translate(-180px, -50px) scale(0.92); }
  }
  .landing-hero {
    text-align: center;
    padding: 36px 20px 18px;
    position: relative;
  }
  .landing-hero::before {
    /* Soft ambient glow behind the hero */
    content: "";
    position: absolute;
    top: -40px;
    left: 50%;
    transform: translateX(-50%);
    width: min(720px, 90%);
    height: 320px;
    background:
      radial-gradient(closest-side, rgba(56,189,248,0.16), transparent 70%),
      radial-gradient(closest-side at 30% 50%, rgba(129,140,248,0.14), transparent 70%);
    pointer-events: none;
    z-index: -1;
    filter: blur(10px);
  }
  .hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    border-radius: 999px;
    background: rgba(56,189,248,0.10);
    border: 1px solid rgba(56,189,248,0.28);
    color: var(--accent);
    font-size: 11.5px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    font-family: 'JetBrains Mono', ui-monospace, monospace;
    margin-bottom: 18px;
    box-shadow: 0 4px 14px rgba(56,189,248,0.18);
    animation: badgePulse 3s ease-in-out infinite;
  }
  @keyframes badgePulse {
    0%, 100% { box-shadow: 0 4px 14px rgba(56,189,248,0.18); }
    50%      { box-shadow: 0 4px 22px rgba(56,189,248,0.45), 0 0 0 4px rgba(56,189,248,0.06); }
  }
  .landing-hero h2 {
    margin: 0 0 14px;
    font-size: clamp(28px, 6.5vw, 52px);
    font-weight: 700;
    letter-spacing: -0.025em;
    /* Looser line-height so descenders (g, p, y) clear the next line */
    line-height: 1.25;
    padding-bottom: 4px;
    background: linear-gradient(180deg, #ffffff, #c4cfe7);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
  }
  .landing-hero h2 .hero-accent {
    background: linear-gradient(90deg, #38bdf8, #818cf8, #c4b5fd, #38bdf8);
    background-size: 300% 100%;
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    white-space: nowrap;
    animation: heroShimmer 6s linear infinite;
  }
  @keyframes heroShimmer {
    0%   { background-position: 0% 50%; }
    100% { background-position: 300% 50%; }
  }
  .landing-hero p {
    margin: 0 auto 24px;
    color: var(--muted);
    font-size: 16px;
    max-width: 620px;
    line-height: 1.55;
  }
  .landing-hero p em {
    color: var(--text);
    font-style: normal;
    font-weight: 600;
  }
  .hero-stats {
    display: inline-flex;
    align-items: stretch;
    gap: 0;
    padding: 14px 8px;
    border: 1px solid var(--panel-border);
    background: rgba(15,23,42,0.45);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: 14px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.25);
  }
  .stat {
    text-align: center;
    padding: 0 22px;
    border-right: 1px solid var(--panel-border);
  }
  .stat:last-child { border-right: none; }
  .stat-value {
    font-family: 'JetBrains Mono', ui-monospace, monospace;
    font-size: 28px;
    font-weight: 700;
    background: linear-gradient(180deg, #ffffff, #93c5fd);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    line-height: 1;
    letter-spacing: -0.02em;
  }
  .stat-label {
    color: var(--muted);
    font-size: 10.5px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-top: 6px;
  }
  @media (max-width: 480px) {
    .landing-hero { padding: 24px 12px 12px; }
    .stat { padding: 0 14px; }
    .stat-value { font-size: 22px; }
  }

  .algo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 16px;
    max-width: 1100px;
    margin: 0 auto;
    width: 100%;
  }
  .algo-card {
    display: flex;
    flex-direction: column;
    gap: 14px;
    padding: 20px;
    border-radius: 16px;
    background: var(--panel);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border: 1px solid var(--panel-border);
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    transition: transform 0.2s var(--spring), border-color 0.2s, box-shadow 0.2s, background 0.2s;
    position: relative;
    overflow: hidden;
  }
  .algo-card:hover {
    transform: translateY(-3px);
    border-color: rgba(56,189,248,0.35);
    box-shadow: 0 14px 40px rgba(0,0,0,0.35), 0 0 0 1px rgba(56,189,248,0.18);
  }
  .algo-card:active { transform: translateY(-1px) scale(0.99); }
  .algo-card .top {
    display: flex;
    align-items: center;
    gap: 12px;
  }
  .algo-card .icon {
    width: 46px; height: 46px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    font-weight: 700;
    line-height: 0;
    padding-bottom: 1px;
    color: white;
    flex-shrink: 0;
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.3), 0 6px 18px rgba(0,0,0,0.35);
    text-shadow: 0 1px 2px rgba(0,0,0,0.3);
  }
  .algo-card .name {
    font-size: 17px;
    font-weight: 700;
    letter-spacing: -0.01em;
  }
  .algo-card .desc {
    color: var(--muted);
    font-size: 13px;
    line-height: 1.5;
  }
  .algo-card .meta {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
    margin-top: auto;
    padding-top: 6px;
  }
  .algo-card .chip {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 3px 9px;
    border-radius: 999px;
    background: rgba(15,23,42,0.55);
    border: 1px solid var(--panel-border);
    color: var(--muted);
    font-size: 11px;
    font-weight: 600;
    font-family: 'JetBrains Mono', monospace;
  }
  .algo-card .chip .dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--accent);
  }
  .algo-card .chip.time .dot { background: #fbbf24; }
  .algo-card .chip.space .dot { background: #67e8f9; }

  /* ---------- Hub category cards (top-level picker) ---------- */
  /* ---------- Top-level mode picker ---------- */
  .mode-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 22px;
    max-width: 1080px;
    width: 100%;
    margin: 0 auto;
  }
  .mode-card {
    display: flex;
    flex-direction: column;
    gap: 18px;
    padding: 32px 28px 28px;
    border-radius: 22px;
    background: var(--panel);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border: 1px solid var(--panel-border);
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: transform 0.25s var(--spring), border-color 0.25s, box-shadow 0.25s;
    animation: cardFadeIn 0.5s ease-out backwards;
    min-height: 240px;
  }
  .mode-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(420px 220px at 50% -10%, rgba(56,189,248,0.10), transparent 70%);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
  }
  .mode-card:hover {
    transform: translateY(-3px);
    border-color: rgba(255,255,255,0.18);
    box-shadow: 0 18px 44px rgba(0,0,0,0.36);
  }
  .mode-card:hover::before { opacity: 1; }
  .mode-card:active { transform: translateY(-1px) scale(0.99); }
  .mode-icon {
    width: 64px; height: 64px;
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 28px;
    font-weight: 700;
    line-height: 0;
    padding-bottom: 1px;
    flex-shrink: 0;
    box-shadow:
      inset 0 1px 0 rgba(255,255,255,0.20),
      inset 0 -2px 0 rgba(0,0,0,0.25),
      0 8px 22px rgba(0,0,0,0.45);
    text-shadow: 0 1px 2px rgba(0,0,0,0.4);
  }
  .mode-body {
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
  }
  .mode-name {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: -0.01em;
    color: var(--text);
  }
  .mode-tag {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 999px;
    background: rgba(56,189,248,0.12);
    border: 1px solid rgba(56,189,248,0.28);
    color: var(--accent);
    font-size: 11px;
    font-weight: 700;
    font-family: 'JetBrains Mono', ui-monospace, monospace;
    letter-spacing: 0.04em;
    width: max-content;
  }
  .mode-card-code .mode-tag {
    background: rgba(217,119,6,0.14);
    border-color: rgba(252,211,77,0.4);
    color: #fcd34d;
  }
  .mode-desc {
    color: var(--muted);
    font-size: 13.5px;
    line-height: 1.55;
  }
  .mode-arrow {
    position: absolute;
    top: 24px; right: 24px;
    color: var(--muted);
    font-size: 28px;
    line-height: 1;
    opacity: 0.5;
    transition: transform 0.25s var(--spring), opacity 0.25s;
  }
  .mode-card:hover .mode-arrow {
    opacity: 1;
    transform: translateX(4px);
  }

  /* ========================================================
     DESIGN PATTERNS
     ======================================================== */
  .pattern-workspace {
    display: flex;
    flex-direction: column;
    flex: 1;
    overflow-y: auto;
  }
  .pattern-info {
    display: flex;
    gap: 20px;
    padding: 16px var(--pad-x);
    border-bottom: 1px solid var(--panel-border);
    background: rgba(15,23,42,0.5);
  }
  .pattern-info-block {
    flex: 1;
  }
  .pattern-info-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--accent);
    margin-bottom: 4px;
  }
  .pattern-info-text {
    color: var(--text);
    font-size: 13.5px;
    line-height: 1.5;
  }
  .pattern-stage {
    flex: 1;
    display: flex;
    align-items: safe center;
    justify-content: safe center;
    padding: 24px;
    overflow: auto;
    min-height: 200px;
  }
  .pattern-svg {
    width: 100%;
    max-width: 800px;
    height: auto;
    max-height: 65vh;
  }
  .pattern-code-panel {
    display: flex;
    flex-direction: column;
    border-top: 1px solid var(--panel-border);
    max-height: 42px;
    overflow: hidden;
    transition: max-height 0.35s ease;
  }
  .pattern-code-panel.open {
    max-height: 340px;
  }
  .pattern-code-toggle {
    display: flex;
    align-items: center;
    gap: 8px;
    width: 100%;
    padding: 10px 16px;
    border: none;
    background: rgba(15,23,42,0.6);
    color: var(--accent);
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    cursor: pointer;
    text-align: left;
  }
  .pattern-code-toggle:hover {
    background: rgba(15,23,42,0.85);
  }
  .pattern-code-toggle-icon {
    display: inline-block;
    font-size: 10px;
    transition: transform 0.35s ease;
  }
  .pattern-code-panel.open .pattern-code-toggle-icon {
    transform: rotate(180deg);
  }
  .pattern-code-pre {
    flex: 1;
    margin: 0;
    padding: 12px 16px !important;
    overflow: auto;
    background: var(--bg-1) !important;
    border-radius: 0 !important;
    font-size: 12.5px !important;
    line-height: 1.6 !important;
  }
  .pattern-code-pre code {
    font-family: 'JetBrains Mono', monospace !important;
    font-size: 12.5px !important;
    white-space: pre !important;
  }
  .sd-edge-dependency {
    stroke: #a1a1aa;
    stroke-width: 1.4;
    stroke-dasharray: 6 4;
    opacity: 0.7;
  }
  #pattern-category {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.06em;
    padding: 3px 10px;
    border-radius: 999px;
    border: 1px solid;
  }

  .category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 18px;
    max-width: 980px;
    width: 100%;
    margin: 0 auto;
  }
  .category-card {
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding: 28px;
    border-radius: 20px;
    background: var(--panel);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border: 1px solid var(--panel-border);
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: transform 0.22s var(--spring), border-color 0.22s, box-shadow 0.22s;
    /* Stagger fade-in on first paint; delay set inline per card via JS */
    animation: cardFadeIn 0.5s ease-out backwards;
  }
  @keyframes cardFadeIn {
    from { opacity: 0; transform: translateY(14px); }
    to   { opacity: 1; transform: translateY(0); }
  }
  .category-card::before {
    content: "";
    position: absolute;
    top: -60px; right: -40px;
    width: 240px; height: 240px;
    background: var(--cat-glow, radial-gradient(circle, rgba(56,189,248,0.18), transparent 70%));
    pointer-events: none;
  }
  .category-card:hover {
    transform: translateY(-4px);
    border-color: rgba(56,189,248,0.4);
    box-shadow: 0 18px 50px rgba(0,0,0,0.4), 0 0 0 1px rgba(56,189,248,0.22);
  }
  /* Placeholder / coming-soon variant - slightly muted, dashed border. */
  .category-card.coming-soon {
    border-style: dashed;
    border-color: rgba(148,163,184,0.22);
  }
  .category-card.coming-soon .cat-icon {
    filter: saturate(0.7);
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.18), 0 6px 16px rgba(0,0,0,0.3);
  }
  .category-card.coming-soon .cat-tag {
    color: var(--muted);
    background: rgba(148,163,184,0.10);
    border: 1px solid rgba(148,163,184,0.2);
    padding: 2px 9px;
    border-radius: 999px;
    display: inline-block;
    font-family: 'JetBrains Mono', ui-monospace, monospace;
    text-transform: none;
    letter-spacing: 0.02em;
  }
  .category-card.coming-soon:hover {
    border-color: rgba(148,163,184,0.45);
    box-shadow: 0 14px 36px rgba(0,0,0,0.32), 0 0 0 1px rgba(148,163,184,0.25);
  }
  .category-card:active { transform: translateY(-1px) scale(0.99); }
  .category-card .cat-top {
    display: flex;
    align-items: center;
    gap: 14px;
    position: relative;
    z-index: 1;
    min-width: 0;
  }
  .category-card .cat-top > div:not(.cat-icon) {
    min-width: 0;
    overflow: hidden;
  }
  .category-card .cat-icon {
    width: 60px; height: 60px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    font-weight: 700;
    line-height: 0;
    padding-bottom: 1px;
    color: white;
    flex-shrink: 0;
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.3), 0 8px 22px rgba(0,0,0,0.4);
    text-shadow: 0 1px 2px rgba(0,0,0,0.3);
  }
  .category-card .cat-name {
    font-size: 21px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 4px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    line-height: 1.25;
  }
  .category-card .cat-tag {
    color: var(--accent);
    font-size: 11.5px;
    font-weight: 700;
    font-family: 'JetBrains Mono', monospace;
    text-transform: uppercase;
    letter-spacing: 0.05em;
  }
  .category-card .cat-desc {
    color: var(--muted);
    font-size: 13.5px;
    line-height: 1.55;
    position: relative;
    z-index: 1;
  }
  .category-card .cat-arrow {
    align-self: flex-end;
    color: var(--accent);
    font-size: 22px;
    line-height: 1;
    margin-top: -6px;
    transition: transform 0.2s var(--spring);
    position: relative;
    z-index: 1;
  }
  .category-card:hover .cat-arrow { transform: translateX(4px); }

  /* Placeholder block shown when a category has no items yet */
  .category-placeholder {
    margin: 12px auto 0;
    max-width: 540px;
    padding: 36px 24px;
    border-radius: 18px;
    background: var(--panel);
    border: 1px dashed var(--panel-border);
    text-align: center;
    color: var(--muted);
  }
  .category-placeholder .ph-icon {
    font-size: 36px;
    margin-bottom: 10px;
    opacity: 0.7;
  }
  .category-placeholder h3 {
    margin: 0 0 8px;
    color: var(--text);
    font-size: 17px;
    font-weight: 700;
  }
  .category-placeholder p {
    margin: 0;
    font-size: 13.5px;
    line-height: 1.55;
  }