:root{
    --ink:#14181c;
    --panel:#1c2126;
    --panel-2:#242a30;
    --paper:#f6f4ee;
    --line:rgba(246,244,238,0.08);
    --mint:#8fe3c7;
    --mint-dim:rgba(143,227,199,0.18);
    --amber:#e8a33d;
    --amber-dim:rgba(232,163,61,0.18);
    --text:#eeece6;
    --text-dim:#a9afb6;
    --danger:#e2695f;
    --radius:14px;
    --font-en:'Manrope',sans-serif;
    --font-ar:'Cairo',sans-serif;
    --font-digit:'Space Mono',monospace;
  }
  *{box-sizing:border-box;}
  html,body{margin:0;padding:0;}
  body{
    background:
      repeating-linear-gradient(0deg, var(--line) 0px, var(--line) 1px, transparent 1px, transparent 32px),
      repeating-linear-gradient(90deg, var(--line) 0px, var(--line) 1px, transparent 1px, transparent 32px),
      var(--ink);
    color:var(--text);
    font-family:var(--font-en);
    min-height:100vh;
    -webkit-font-smoothing:antialiased;
  }
  html[dir="rtl"] body{ font-family:var(--font-ar); }
  html[dir="rtl"] .digit, html[dir="rtl"] .keypad-display, html[dir="rtl"] .result-number{
    direction:ltr;
  }
  a{color:inherit;}
  button{font-family:inherit;}
  .wrap{max-width:1180px;margin:0 auto;padding:0 24px;}

  /* HEADER */
  header{
    position:sticky;top:0;z-index:50;
    background:rgba(20,24,28,0.86);
    backdrop-filter:blur(10px);
    border-bottom:1px solid rgba(246,244,238,0.09);
  }
  .header-inner{display:flex;align-items:center;justify-content:space-between;padding:16px 24px;}
  .logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:20px;letter-spacing:-0.02em;}
  .logo-mark{
    width:34px;height:34px;border-radius:9px;
    background:linear-gradient(155deg, var(--mint), var(--amber));
    display:flex;align-items:center;justify-content:center;
    font-family:var(--font-digit);font-weight:700;color:#14181c;font-size:15px;
  }
  nav{display:flex;align-items:center;gap:28px;}
  nav a{text-decoration:none;color:var(--text-dim);font-weight:600;font-size:14.5px;transition:color .15s;}
  nav a:hover{color:var(--text);}
  .lang-toggle{
    display:flex;align-items:center;border:1px solid rgba(246,244,238,0.18);
    border-radius:999px;padding:3px;background:var(--panel);gap:2px;cursor:pointer;
  }
  .lang-toggle button{
    border:none;background:transparent;color:var(--text-dim);
    padding:6px 13px;border-radius:999px;font-size:13px;font-weight:700;cursor:pointer;
    transition:all .18s;font-family:var(--font-en);
  }
  .lang-toggle button.active{background:var(--mint);color:#0e1a16;}

  /* HERO */
  .hero{padding:64px 0 40px;}
  .hero-grid{display:grid;grid-template-columns:1.05fr 0.95fr;gap:56px;align-items:center;}
  .eyebrow{
    display:inline-flex;align-items:center;gap:8px;font-family:var(--font-digit);
    font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--amber);
    border:1px solid var(--amber-dim);background:var(--amber-dim);
    padding:6px 12px;border-radius:999px;margin-bottom:20px;
  }
  html[dir="rtl"] .eyebrow{font-family:var(--font-ar);letter-spacing:0;}
  .hero h1{
    font-size:52px;line-height:1.06;letter-spacing:-0.03em;margin:0 0 20px;font-weight:800;
  }
  html[dir="rtl"] .hero h1{letter-spacing:0;}
  .hero h1 em{color:var(--mint);font-style:normal;}
  .hero p{font-size:17px;line-height:1.6;color:var(--text-dim);max-width:480px;margin:0 0 28px;}
  .hero-ctas{display:flex;gap:12px;}
  .btn{
    border:none;border-radius:10px;padding:13px 22px;font-weight:700;font-size:14.5px;
    cursor:pointer;transition:transform .12s, opacity .12s;
  }
  .btn:active{transform:scale(0.97);}
  .btn-primary{background:var(--mint);color:#0e1a16;}
  .btn-primary:hover{opacity:.9;}
  .btn-ghost{background:transparent;color:var(--text);border:1px solid rgba(246,244,238,0.22);}
  .btn-ghost:hover{border-color:var(--text);}

  /* HERO CALCULATOR (signature element) */
  .device{
    background:var(--panel);border-radius:22px;padding:20px;
    border:1px solid rgba(246,244,238,0.08);
    box-shadow:0 30px 60px -20px rgba(0,0,0,0.55);
  }
  .device-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px;padding:0 4px;}
  .device-dots{display:flex;gap:6px;}
  .device-dots span{width:8px;height:8px;border-radius:50%;background:rgba(246,244,238,0.18);}
  .device-label{font-family:var(--font-digit);font-size:11px;color:var(--text-dim);letter-spacing:.08em;}
  .display{
    background:#0e1a16;border-radius:14px;padding:26px 20px;margin-bottom:14px;
    border:1px solid rgba(143,227,199,0.15);
  }
  .display-sub{font-family:var(--font-digit);font-size:12px;color:rgba(143,227,199,0.55);min-height:16px;text-align:right;}
  .display-main{
    font-family:var(--font-digit);font-size:40px;font-weight:700;color:var(--mint);
    text-align:right;text-shadow:0 0 18px rgba(143,227,199,0.35);
    overflow:hidden;text-overflow:ellipsis;white-space:nowrap;
  }
  .keypad{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;}
  .key{
    background:var(--panel-2);border:1px solid rgba(246,244,238,0.06);
    border-radius:10px;padding:16px 0;font-family:var(--font-digit);font-size:17px;
    color:var(--text);cursor:pointer;transition:background .1s, transform .08s;
  }
  .key:hover{background:#2b323a;}
  .key:active{transform:scale(0.95);}
  .key.op{color:var(--amber);}
  .key.clear{color:var(--danger);}
  .key.equals{background:var(--mint);color:#0e1a16;font-weight:700;}
  .key.equals:hover{opacity:.9;background:var(--mint);}
  .key.zero{grid-column:span 2;}

  /* CATEGORY SECTIONS */
  section.cats{padding:36px 0 80px;}
  .section-head{margin-bottom:28px;}
  .section-head .kicker{
    font-family:var(--font-digit);font-size:12px;color:var(--text-dim);
    letter-spacing:.14em;text-transform:uppercase;margin-bottom:8px;
  }
  html[dir="rtl"] .section-head .kicker{font-family:var(--font-ar);letter-spacing:0;}
  .section-head h2{font-size:28px;margin:0;letter-spacing:-0.02em;font-weight:800;}

  .cat-block{margin-bottom:44px;}
  .cat-title{
    display:flex;align-items:center;gap:12px;margin-bottom:16px;
  }
  .cat-title .idx{
    font-family:var(--font-digit);font-size:13px;color:var(--ink);
    background:var(--amber);width:28px;height:28px;border-radius:8px;
    display:flex;align-items:center;justify-content:center;font-weight:700;flex:none;
  }
  .cat-title h3{font-size:19px;margin:0;font-weight:700;}
  .card-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;}
  .card{
    background:var(--panel);border:1px solid rgba(246,244,238,0.08);
    border-radius:var(--radius);padding:20px;cursor:pointer;
    transition:border-color .15s, transform .12s, background .15s;
    display:block;text-decoration:none;color:inherit;
  }
  .card:hover{border-color:var(--mint);transform:translateY(-2px);background:var(--panel-2);}
  .card-icon{
    width:38px;height:38px;border-radius:9px;background:var(--mint-dim);
    display:flex;align-items:center;justify-content:center;margin-bottom:14px;
    font-family:var(--font-digit);color:var(--mint);font-weight:700;font-size:15px;
  }
  .card h4{margin:0 0 6px;font-size:16px;font-weight:700;}
  .card p{margin:0;font-size:13.5px;color:var(--text-dim);line-height:1.5;}

  /* Vertical side-rail ad: only shown when there's real empty space beside the content column */
  .side-ad-left{
    position:fixed; top:50%; left:16px; transform:translateY(-50%);
    z-index:40; width:160px; min-height:600px;
    display:flex; align-items:center; justify-content:center;
  }
  @media (max-width:1600px){ .side-ad-left{ display:none; } }

  /* MODAL */
  .modal-overlay{
    position:fixed;inset:0;background:rgba(10,12,14,0.72);backdrop-filter:blur(4px);
    display:none;align-items:center;justify-content:center;z-index:100;padding:20px;
  }
  .modal-overlay.open{display:flex;}
  .modal{
    background:var(--panel);border-radius:18px;max-width:460px;width:100%;
    border:1px solid rgba(246,244,238,0.1);max-height:88vh;overflow-y:auto;
    box-shadow:0 40px 80px -20px rgba(0,0,0,0.6);
  }
  .modal-head{
    display:flex;justify-content:space-between;align-items:center;
    padding:20px 22px;border-bottom:1px solid rgba(246,244,238,0.08);
  }
  .modal-head h3{margin:0;font-size:18px;font-weight:800;}
  .modal-close{
    background:var(--panel-2);border:none;color:var(--text);width:30px;height:30px;
    border-radius:8px;cursor:pointer;font-size:16px;line-height:1;
  }
  .modal-body{padding:22px;}
  .field{margin-bottom:16px;}
  .field label{display:block;font-size:13px;color:var(--text-dim);margin-bottom:7px;font-weight:600;}
  .field input, .field select{
    width:100%;background:var(--panel-2);border:1px solid rgba(246,244,238,0.12);
    border-radius:9px;padding:11px 13px;color:var(--text);font-size:15px;font-family:var(--font-digit);
  }
  html[dir="rtl"] .field input, html[dir="rtl"] .field select{font-family:var(--font-ar);}
  .field input:focus, .field select:focus{outline:2px solid var(--mint);border-color:transparent;}
  .field-row{display:grid;grid-template-columns:1fr 1fr;gap:12px;}
  .calc-btn{
    width:100%;background:var(--mint);color:#0e1a16;border:none;border-radius:9px;
    padding:13px;font-weight:800;font-size:14.5px;cursor:pointer;margin-top:4px;
  }
  .calc-btn:hover{opacity:.9;}
  .result-box{
    margin-top:18px;background:#0e1a16;border:1px solid rgba(143,227,199,0.18);
    border-radius:12px;padding:16px 18px;display:none;
  }
  .result-box.show{display:block;}
  .result-label{font-size:12px;color:var(--text-dim);margin-bottom:4px;font-weight:600;}
  .result-number{font-family:var(--font-digit);font-size:26px;font-weight:700;color:var(--mint);}
  .result-note{font-size:12.5px;color:var(--text-dim);margin-top:8px;line-height:1.5;}

  /* FOOTER */
  footer{border-top:1px solid rgba(246,244,238,0.08);padding:32px 0;margin-top:20px;}
  .footer-inner{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:12px;}
  .footer-inner p{margin:0;font-size:13px;color:var(--text-dim);}

  @media (max-width:860px){
    .hero-grid{grid-template-columns:1fr;}
    .hero h1{font-size:38px;}
    .card-grid{grid-template-columns:1fr 1fr;}
    nav{display:none;}
  }
  @media (max-width:540px){
    .card-grid{grid-template-columns:1fr;}
    .field-row{grid-template-columns:1fr;}
    .display-main{font-size:30px;}
  }

  :focus-visible{outline:2px solid var(--mint);outline-offset:2px;}