body {
    font-family: 'Segoe UI', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #fff;
    color: #333;
    line-height: 1.4;
    font-size: 15px;
}

main {
    max-width: 900px;
    margin: auto;
    padding: 15px;
}

.hero {
    text-align: center;
    padding: 20px 0 15px 0;
}

.hero h1 {
    font-size: 2.2em;
    margin-bottom: 0.3em;
}

.hero p {
    margin-bottom: 0.8em;
}

.buttons .btn {
    display: inline-block;
    padding: 8px 16px;
    margin: 5px;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
}

.btn.primary {
    background-color: #0078d7;
    color: white;
}

.btn.secondary {
    border: 1px solid #0078d7;
    color: #0078d7;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin-bottom: 25px;
}

.feature h3 {
    margin-bottom: 0.4em;
}

.how-it-works h2 {
    font-size: 1.5em;
    margin-bottom: 0.4em;
}

.modes {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 15px;
}

.mode h3 {
    margin-bottom: 0.4em;
}

.mode ul {
    padding-left: 20px;
    margin-top: 0.2em;
}

kbd {
    background: #f4f4f4;
    border: 1px solid #ccc;
    border-radius: 4px;
    padding: 2px 5px;
    font-family: monospace;
}

/* จัดวาง 3 ปุ่มเรียงกัน */
  .ext-links { display:flex; flex-wrap:wrap; gap:.5rem; }

  /* ปุ่มแบบลิงก์เรียบ ๆ ไม่มีกรอบ ไม่มีขีดเส้นใต้ */
  .ext-link{
    display:inline-flex; align-items:center; gap:.4rem;
    text-decoration:none; border:0; outline:0; padding:.25rem .4rem;
    border-radius:.4rem; font-weight:600; color:#1d1d1f;
    background:transparent;
  }
  .ext-link:hover{ background:#f5f5f7; text-decoration:none; }
  .ext-link:focus-visible{ box-shadow:0 0 0 3px rgba(0,113,227,.25); }

  /* ขนาดไอคอน */
  .ext-link i{ font-size:18px; line-height:1; }

  /* สีแบรนด์ (Edge / Firefox / Chrome) */
  .ext-link.edge i{ color:#0078D7; }      /* Edge */   /* :contentReference[oaicite:1]{index=1} */
  .ext-link.firefox i{ color:#FF7139; }   /* Firefox */ /* :contentReference[oaicite:2]{index=2} */
  .ext-link.chrome i{ color:#4285F4; }    /* Chrome */  /* :contentReference[oaicite:3]{index=3} */