/*!
 * AkihiroLabs — NumConv — styles
 * https://github.com/AkihiroZayar/numconv
 */
      *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

      :root {
        --bg: #f5f5f7;
        --surface: #ffffff;
        --surface2: #f0f0f3;
        --primary: #4f46e5;
        --primary-light: #e8e7fb;
        --green: #16a34a;
        --green-light: #dcfce7;
        --red: #dc2626;
        --red-light: #fee2e2;
        --orange: #ea580c;
        --text: #1e1e2e;
        --text2: #6b7280;
        --text3: #9ca3af;
        --border: #e5e7eb;
        --radius: 12px;
        --shadow: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
        --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
        --mono: 'DM Mono', monospace;
        --display: 'Space Grotesk', sans-serif;
        --body: 'DM Sans', sans-serif;
      }

      html { scroll-behavior: smooth; }
      body {
        background: var(--bg);
        color: var(--text);
        font-family: var(--body);
        min-height: 100vh;
        -webkit-font-smoothing: antialiased;
      }

      .container { max-width: 880px; margin: 0 auto; padding: 0 20px; }

      /* ── NAV ── */
      nav {
        position: sticky; top: 0; z-index: 100;
        background: rgba(255,255,255,0.85);
        backdrop-filter: blur(14px);
        border-bottom: 1px solid var(--border);
        padding: 0 20px;
      }
      .nav-inner {
        max-width: 880px; margin: 0 auto;
        display: flex; align-items: center; justify-content: space-between;
        height: 56px;
      }
      .logo {
        font-family: var(--display);
        font-size: 20px; font-weight: 700;
        color: var(--text);
      }
      .logo span { color: var(--primary); }
      .logo .logo-lab {
        font-family: var(--body); font-size: 11px; font-weight: 500;
        color: var(--text3); letter-spacing: 0; margin-left: 6px;
      }
      .nav-tabs { display: flex; gap: 2px; }
      .nav-tab {
        font-family: var(--body);
        font-size: 13px; font-weight: 500;
        color: var(--text2);
        padding: 6px 14px; border-radius: 8px;
        cursor: pointer; border: none;
        background: transparent; transition: all 0.15s;
      }
      .nav-tab:hover { color: var(--text); background: var(--surface2); }
      .nav-tab.active { color: var(--primary); background: var(--primary-light); }

      /* ── HERO ── */
      .hero { padding: 48px 0 32px; text-align: center; }
      .hero-label {
        font-size: 13px; font-weight: 600;
        color: var(--primary);
        letter-spacing: 1px;
        margin-bottom: 10px; text-transform: uppercase;
      }
      .hero-title {
        font-family: var(--display);
        font-size: clamp(26px, 5vw, 40px);
        font-weight: 700; color: var(--text);
        line-height: 1.2; margin-bottom: 10px;
      }
      .hero-sub { font-size: 15px; color: var(--text2); }

      /* ── PAGES ── */
      .page { display: none; }
      .page.active { display: block; }

      /* ── CONVERTER GRID ── */
      .converter-grid {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 14px; margin-bottom: 20px;
      }
      @media (max-width: 600px) {
        .converter-grid { grid-template-columns: 1fr; }
        .nav-tabs { gap: 0; }
        .nav-tab { padding: 6px 10px; font-size: 12px; }
      }

      .base-card {
        background: var(--surface);
        border: 1.5px solid var(--border);
        border-radius: var(--radius);
        padding: 18px 20px;
        transition: border-color 0.15s, box-shadow 0.15s;
        box-shadow: var(--shadow);
      }
      .base-card:hover { border-color: #d0d0d6; }
      .base-card.active { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-light); }

      .base-header {
        display: flex; justify-content: space-between;
        align-items: center; margin-bottom: 10px;
      }
      .base-name {
        font-family: var(--display);
        font-size: 12px; font-weight: 600;
        color: var(--text); letter-spacing: 0.5px;
        text-transform: uppercase;
      }
      .base-badge {
        font-family: var(--mono); font-size: 11px;
        background: var(--surface2);
        border-radius: 6px; padding: 2px 8px;
        color: var(--text2);
      }
      .base-input {
        width: 100%; background: transparent;
        border: none; outline: none;
        font-family: var(--mono);
        font-size: 22px; font-weight: 500;
        color: var(--text);
        caret-color: var(--primary);
      }
      .base-input::placeholder { color: var(--text3); font-size: 17px; }
      .base-error {
        font-family: var(--mono); font-size: 11px;
        color: var(--red); margin-top: 6px; min-height: 16px;
      }
      .base-copy {
        font-size: 12px; font-weight: 500;
        color: var(--text3); margin-top: 8px;
        cursor: pointer; background: none;
        border: none; padding: 0; transition: color 0.15s;
      }
      .base-copy:hover { color: var(--primary); }

      /* ── ACTION BUTTONS ── */
      .actions {
        display: flex; gap: 8px;
        margin-bottom: 24px; flex-wrap: wrap;
      }
      .btn {
        font-family: var(--body);
        font-size: 13px; font-weight: 500;
        padding: 8px 16px; border-radius: 8px;
        border: 1px solid var(--border);
        background: var(--surface);
        color: var(--text2); cursor: pointer;
        transition: all 0.15s; box-shadow: var(--shadow);
      }
      .btn:hover { border-color: #c5c7cc; color: var(--text); }
      .btn.primary {
        border-color: var(--primary);
        color: #fff; background: var(--primary);
      }
      .btn.primary:hover { background: #4338ca; }

      /* ── PANELS ── */
      .panel {
        background: var(--surface);
        border: 1px solid var(--border);
        border-radius: var(--radius);
        padding: 20px; margin-bottom: 16px;
        box-shadow: var(--shadow);
      }
      .panel-title {
        font-family: var(--display);
        font-size: 12px; font-weight: 600;
        color: var(--text2); letter-spacing: 0.5px;
        margin-bottom: 14px; text-transform: uppercase;
      }

      /* ── BIT VISUALIZER ── */
      .bits-row { display: flex; flex-wrap: wrap; gap: 8px; }
      .bit-group { display: flex; gap: 3px; }
      .bit-cell { display: flex; flex-direction: column; align-items: center; gap: 3px; }
      .bit-box {
        width: 34px; height: 34px; border-radius: 8px;
        border: 1px solid var(--border);
        display: flex; align-items: center; justify-content: center;
        font-family: var(--mono); font-size: 15px; font-weight: 500;
        transition: all 0.15s;
      }
      .bit-box.one {
        background: var(--primary-light);
        border-color: var(--primary);
        color: var(--primary);
      }
      .bit-box.zero { background: var(--surface2); color: var(--text3); }
      .bit-pos { font-family: var(--mono); font-size: 9px; color: var(--text3); }

      /* ── REFERENCE TABLE ── */
      .ref-table { width: 100%; border-collapse: collapse; font-family: var(--mono); font-size: 13px; }
      .ref-table th {
        font-family: var(--display); font-size: 11px; font-weight: 600;
        color: var(--text2); text-align: left;
        padding: 10px 14px; border-bottom: 1.5px solid var(--border);
        text-transform: uppercase; letter-spacing: 0.5px;
      }
      .ref-table td {
        padding: 7px 14px; border-bottom: 1px solid var(--surface2); color: var(--text);
      }
      .ref-table tr:hover td { background: var(--surface2); }
      .ref-table tr.hl td { background: var(--primary-light); color: var(--primary); }
      .ref-table td:first-child { font-weight: 500; }

      /* ── ASCII TABLE ── */
      .ascii-grid {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(96px, 1fr));
        gap: 6px;
      }
      .ascii-cell {
        background: var(--surface2); border: 1px solid var(--border);
        border-radius: 8px; padding: 8px;
        cursor: pointer; transition: all 0.12s;
      }
      .ascii-cell:hover { border-color: var(--primary); background: var(--primary-light); }
      .ascii-cell.hl { border-color: var(--green); background: var(--green-light); }
      .ascii-char { font-family: var(--display); font-size: 16px; font-weight: 600; color: var(--text); }
      .ascii-vals { font-family: var(--mono); font-size: 9px; color: var(--text3); margin-top: 4px; line-height: 1.5; }

      /* ── QUIZ ── */
      .quiz-card {
        background: var(--surface); border: 1px solid var(--border);
        border-radius: 16px; padding: 32px; text-align: center;
        max-width: 540px; margin: 0 auto; box-shadow: var(--shadow-md);
      }
      .quiz-question { font-size: 14px; color: var(--text2); margin-bottom: 10px; font-weight: 500; }
      .quiz-number {
        font-family: var(--display);
        font-size: 40px; font-weight: 700;
        color: var(--text); margin-bottom: 6px;
      }
      .quiz-hint {
        font-family: var(--mono); font-size: 12px;
        color: var(--primary); margin-bottom: 24px;
      }
      .quiz-options { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-bottom: 16px; }
      .quiz-opt {
        font-family: var(--mono); font-size: 15px; font-weight: 500;
        padding: 14px; border-radius: 10px;
        border: 1.5px solid var(--border);
        background: var(--surface); color: var(--text);
        cursor: pointer; transition: all 0.15s;
      }
      .quiz-opt:hover { border-color: var(--primary); color: var(--primary); }
      .quiz-opt.correct { border-color: var(--green); background: var(--green-light); color: var(--green); }
      .quiz-opt.wrong { border-color: var(--red); background: var(--red-light); color: var(--red); }
      .quiz-feedback { font-family: var(--mono); font-size: 13px; min-height: 20px; margin-bottom: 14px; }
      .quiz-score { display: flex; justify-content: center; gap: 32px; margin-bottom: 20px; }
      .score-item { text-align: center; }
      .score-val { font-family: var(--display); font-size: 28px; font-weight: 700; }
      .score-val.green { color: var(--green); }
      .score-val.red { color: var(--red); }
      .score-label { font-size: 11px; font-weight: 500; color: var(--text3); text-transform: uppercase; letter-spacing: 0.5px; }

      /* ── HISTORY ── */
      .history-list { display: flex; flex-direction: column; gap: 6px; }
      .history-row {
        display: flex; align-items: center; gap: 12px;
        background: var(--surface2); border: 1px solid var(--border);
        border-radius: 8px; padding: 10px 14px;
        font-family: var(--mono); font-size: 12px;
        cursor: pointer; transition: border-color 0.12s;
      }
      .history-row:hover { border-color: var(--primary); }
      .history-dec { color: var(--text); font-weight: 500; min-width: 50px; }
      .history-rest { color: var(--text2); flex: 1; }
      .history-time { color: var(--text3); font-size: 10px; }

      /* ── SEARCH INPUT ── */
      .search-input {
        background: var(--surface2); border: 1px solid var(--border);
        border-radius: 8px; padding: 8px 12px;
        font-family: var(--mono); font-size: 12px;
        color: var(--text); outline: none; width: 200px;
        transition: border-color 0.15s;
      }
      .search-input:focus { border-color: var(--primary); }

      /* ── FOOTER ── */
      footer {
        text-align: center; padding: 40px 20px;
        font-size: 13px; color: var(--text3);
      }
      footer span { color: var(--primary); font-weight: 500; }

/* Install button (shown only when the browser offers install) */
.install-btn[hidden] { display: none; }
.install-btn { margin-top: 12px; }