:root{
    --navy:#0F1F4D; --navy-2:#1e3a8a; --navy-ink:#0b1633;
    --green:#10b981; --green-dk:#059669; --green-soft:rgba(16,185,129,.12);
    --ink:#0f1729; --muted:#64748b; --line:#e6eaf2; --bg:#f5f7fb;
    --white:#fff; --danger:#ef4444;
    --shadow:0 30px 80px rgba(8,15,40,.45);
    --r:22px;
  }
  *{box-sizing:border-box}
  html,body{margin:0;height:100%}
  body{
    font-family:'Inter',system-ui,sans-serif;
    color:var(--ink);
    background:
      radial-gradient(1200px 600px at 80% -10%, rgba(16,185,129,.18), transparent 60%),
      radial-gradient(900px 500px at 0% 110%, rgba(30,58,138,.55), transparent 55%),
      linear-gradient(160deg,#0c1a3e 0%, #0F1F4D 45%, #0a1430 100%);
    min-height:100%;
    display:flex; flex-direction:column; align-items:center;
    padding:26px 16px 40px;
  }
  .brand{
    display:flex;align-items:center;gap:9px;margin-bottom:18px;
    color:#fff;letter-spacing:-.02em;
  }
  .brand .logo{font-family:'Poppins';font-weight:800;font-size:24px;font-style:italic;letter-spacing:-.02em}
  .brand .logo-img{height:30px;width:auto;display:block}
  .brand .logo .dot{color:var(--green)}
  .brand .tag{font-size:12px;color:rgba(255,255,255,.55);font-weight:500;border-left:1px solid rgba(255,255,255,.2);padding-left:9px}

  /* phone-style device */
  .device{
    width:100%;max-width:412px;background:var(--white);border-radius:var(--r);
    box-shadow:var(--shadow);overflow:hidden;position:relative;
    border:1px solid rgba(255,255,255,.08);
  }
  .device::before{content:"";position:absolute;inset:0 0 auto 0;height:5px;
    background:linear-gradient(90deg,var(--navy-2),var(--green));}

  .screen{display:none;padding:30px 26px 28px;animation:fade .45s ease both}
  .screen.active{display:block}
  @keyframes fade{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

  .eyebrow{font-family:'Poppins';font-weight:700;font-size:11px;letter-spacing:.18em;
    text-transform:uppercase;color:var(--green-dk);text-align:center;margin-bottom:10px}
  h1{font-family:'Poppins';font-weight:800;font-size:25px;line-height:1.15;
    text-align:center;margin:0 0 8px;letter-spacing:-.02em}
  .sub{text-align:center;color:var(--muted);font-size:14.5px;line-height:1.5;margin:0 auto 22px;max-width:300px}

  .lockmark{width:74px;height:74px;margin:4px auto 16px;border-radius:20px;
    display:flex;align-items:center;justify-content:center;
    background:linear-gradient(135deg,var(--green) 0%,var(--green-dk) 100%);
    box-shadow:0 14px 30px rgba(16,185,129,.4);position:relative}
  .lockmark svg{width:46px;height:46px}

  .btn{display:flex;align-items:center;justify-content:center;gap:9px;width:100%;
    border:none;border-radius:14px;padding:15px 20px;font-family:'Poppins';
    font-weight:700;font-size:15px;cursor:pointer;transition:.22s;text-decoration:none}
  .btn-primary{background:linear-gradient(135deg,var(--green),var(--green-dk));color:#fff;
    box-shadow:0 12px 26px rgba(16,185,129,.34)}
  .btn-primary:hover{transform:translateY(-2px);box-shadow:0 16px 32px rgba(16,185,129,.46)}
  .btn-ghost{background:#eef1f7;color:var(--navy);margin-top:10px}
  .btn-ghost:hover{background:#e3e8f2}
  .btn-navy{background:linear-gradient(135deg,var(--navy-2),var(--navy));color:#fff}
  .btn:disabled{opacity:.5;cursor:not-allowed;transform:none}

  /* compose */
  .chat{background:var(--bg);border:1px solid var(--line);border-radius:18px;padding:14px;margin-bottom:14px}
  .chat .from{font-size:11px;color:var(--muted);font-weight:600;margin:0 0 8px;display:flex;align-items:center;gap:6px}
  .chat .from .ring{width:8px;height:8px;border-radius:50%;background:var(--green)}
  textarea{width:100%;border:none;background:transparent;resize:none;min-height:120px;
    font-family:'Inter';font-size:16px;line-height:1.5;color:var(--ink);outline:none}
  .emojis{display:flex;gap:6px;flex-wrap:wrap;margin-top:6px;justify-content:center}
  .emojis button{border:none;background:#fff;border:1px solid var(--line);border-radius:10px;
    width:34px;height:34px;font-size:17px;cursor:pointer;transition:.15s}
  .emojis button:hover{transform:scale(1.12);border-color:var(--green)}
  .count{text-align:right;font-size:12px;color:var(--muted);margin:8px 2px 16px}

  /* encrypting / decrypting bars */
  .cipher{font-family:'JetBrains Mono','Courier New',monospace;font-size:15px;line-height:1.9;
    word-break:break-word;text-align:center;min-height:80px;display:flex;align-items:center;
    justify-content:center;flex-wrap:wrap;gap:3px;padding:8px 4px}
  .bar{display:inline-block;height:15px;border-radius:3px;background:var(--ink);
    animation:pop .3s ease both}
  @keyframes pop{from{transform:scaleX(0)}to{transform:scaleX(1)}}
  .spin{width:46px;height:46px;border-radius:50%;border:3px solid var(--green-soft);
    border-top-color:var(--green);animation:spin 1s linear infinite;margin:6px auto 16px}
  @keyframes spin{to{transform:rotate(360deg)}}
  .status{text-align:center;font-family:'Poppins';font-weight:600;color:var(--navy);font-size:15px}

  /* result */
  .qrwrap{width:200px;height:200px;margin:6px auto 18px;background:#fff;border-radius:18px;
    border:1px solid var(--line);box-shadow:0 10px 26px rgba(8,15,40,.1);padding:12px;
    display:flex;align-items:center;justify-content:center}
  .qrwrap canvas,.qrwrap img{width:100%!important;height:100%!important;border-radius:6px}
  .pinbox{background:var(--green-soft);border:1px dashed var(--green);border-radius:16px;
    padding:16px;text-align:center;margin-bottom:16px}
  .pinbox .lbl{font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--green-dk);font-weight:700}
  .pinbox .pin{font-family:'Poppins';font-weight:800;font-size:38px;letter-spacing:.34em;
    color:var(--navy);margin:6px 0 2px;padding-left:.34em}
  .pinbox .hint{font-size:12px;color:var(--muted)}
  .row{display:flex;gap:10px}
  .row .btn{margin-top:0}
  .note{background:#fff7ed;border:1px solid #fed7aa;color:#9a3412;border-radius:12px;
    padding:11px 13px;font-size:12.5px;line-height:1.5;margin-top:14px;display:flex;gap:8px}

  /* recipient open */
  .envelope{width:120px;height:120px;margin:6px auto 18px;position:relative;cursor:pointer}
  .envelope .glow{position:absolute;inset:0;border-radius:50%;
    background:radial-gradient(circle,rgba(16,185,129,.35),transparent 65%);
    animation:pulse 2.4s ease-in-out infinite}
  @keyframes pulse{0%,100%{transform:scale(.9);opacity:.7}50%{transform:scale(1.1);opacity:1}}
  .envelope .em{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;font-size:62px}

  /* pin entry */
  .pininput{display:flex;gap:10px;justify-content:center;margin:6px 0 14px}
  .pininput input{width:54px;height:64px;text-align:center;font-family:'Poppins';font-weight:700;
    font-size:26px;border:2px solid var(--line);border-radius:14px;outline:none;transition:.15s;color:var(--navy)}
  .pininput input:focus{border-color:var(--green);box-shadow:0 0 0 4px var(--green-soft)}
  .attempts{text-align:center;font-size:13px;color:var(--danger);font-weight:600;min-height:18px;margin-bottom:12px}
  .shake{animation:shake .4s}
  @keyframes shake{0%,100%{transform:none}20%,60%{transform:translateX(-7px)}40%,80%{transform:translateX(7px)}}

  /* reveal + destruct */
  .revealcard{background:var(--bg);border:1px solid var(--line);border-radius:18px;padding:20px;
    font-size:17px;line-height:1.55;text-align:left;min-height:90px;color:var(--ink)}
  .selfd{display:flex;align-items:center;justify-content:center;gap:8px;margin-top:16px;
    color:var(--danger);font-weight:600;font-size:13.5px}
  .selfd .dotc{width:7px;height:7px;border-radius:50%;background:var(--danger);animation:pulse 1.1s infinite}
  .destroyed{text-align:center;padding:14px 0}
  .destroyed .big{font-size:60px;margin-bottom:6px}
  .fadeaway{animation:dissolve 1.1s forwards}
  @keyframes dissolve{to{opacity:0;filter:blur(10px);transform:scale(.96)}}

  /* demo controls */
  .demobar{max-width:412px;width:100%;margin-top:18px;background:rgba(255,255,255,.06);
    border:1px solid rgba(255,255,255,.12);border-radius:14px;padding:12px 14px;backdrop-filter:blur(8px)}
  .demobar .dl{font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:rgba(255,255,255,.55);
    font-weight:700;margin-bottom:9px;text-align:center}
  .demobar .seg{display:flex;gap:8px}
  .demobar button{flex:1;border:1px solid rgba(255,255,255,.18);background:rgba(255,255,255,.04);
    color:#fff;border-radius:10px;padding:9px;font-family:'Poppins';font-weight:600;font-size:12.5px;cursor:pointer;transition:.18s}
  .demobar button:hover{background:rgba(16,185,129,.2);border-color:var(--green)}
  .toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%) translateY(20px);
    background:var(--navy);color:#fff;padding:12px 18px;border-radius:12px;font-weight:600;font-size:14px;
    opacity:0;transition:.3s;z-index:50;box-shadow:var(--shadow)}
  .toast.show{opacity:1;transform:translateX(-50%) translateY(0)}
  .modal{position:fixed;inset:0;background:rgba(8,15,40,.55);backdrop-filter:blur(4px);display:none;align-items:center;justify-content:center;padding:18px;z-index:60}
  .modal.show{display:flex}
  .modal-card{background:#fff;border-radius:20px;max-width:384px;width:100%;overflow:hidden;box-shadow:var(--shadow);animation:fade .3s ease both}
  .modal-head{background:linear-gradient(135deg,var(--navy-2),var(--navy));color:#fff;padding:15px 20px;font-family:'Poppins';font-weight:700;font-size:15px;display:flex;justify-content:space-between;align-items:center}
  .modal-head .x{cursor:pointer;opacity:.75;font-size:22px;line-height:1}
  .modal-body{padding:20px}
  .field{margin-bottom:14px}
  .field label{display:block;font-size:12px;font-weight:600;color:var(--muted);margin-bottom:6px}
  .field input{width:100%;border:1px solid var(--line);border-radius:11px;padding:12px;font-size:15px;font-family:'Inter';outline:none}
  .field input:focus{border-color:var(--green);box-shadow:0 0 0 3px var(--green-soft)}
  .epreview{background:var(--bg);border:1px solid var(--line);border-radius:14px;padding:14px;margin-bottom:14px;font-size:13px}
  .epreview .er{display:flex;gap:8px;margin-bottom:5px;color:var(--muted)}
  .epreview .er b{color:var(--ink);min-width:62px;font-weight:600}
  .epreview .epin{font-family:'Poppins';font-weight:800;font-size:24px;letter-spacing:.2em;color:var(--navy);text-align:center;margin-top:8px;padding-left:.2em}
  @media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}