/* Trang giới thiệu /viet-bai-seo — cùng bộ màu với app Viết bài SEO (body.sw-user-app):
   nền trắng/xám trung tính, chữ gần đen, vàng #d99000 làm điểm nhấn,
   gradient vàng–cam CHỈ cho nút chính, khối tối #1d1512 cho phần quy trình. */
.sl{
  --sl-bg:#f4f4f5; --sl-surface:#fff; --sl-surface-2:#f9f9fa;
  --sl-ink:#11100e; --sl-ink-soft:#33322f; --sl-muted:#5c5c5c; --sl-faint:#8e8e8e;
  --sl-border:#e8e8ea; --sl-border-2:#eeeef0;
  --sl-gold:#d99000; --sl-gold-d:#a06a00; --sl-gold-l:#FFF7E3; --sl-gold-bd:rgba(255,183,0,.45);
  --sl-grad:linear-gradient(135deg,#ffd700,#ffa500); --sl-grad-h:linear-gradient(135deg,#ffc400,#ff9500);
  --sl-on-grad:#241a00; --sl-dark:#1d1512; --sl-dark-2:#2a211c; --sl-dark-bd:#3a2f28;
  --sl-mono:'JetBrains Mono',ui-monospace,monospace;
  margin:0;background:var(--sl-surface);color:var(--sl-ink);
  font-family:'Be Vietnam Pro',system-ui,sans-serif;-webkit-font-smoothing:antialiased;line-height:1.5;
}
.sl *,.sl *::before,.sl *::after{box-sizing:border-box}
:where(.sl) :where(h1,h2,h3,p,ol,ul){margin:0;padding:0}
:where(.sl) a{color:inherit;text-decoration:none}
.sl ::selection{background:rgba(255,183,0,.45)}
.sl-wrap{max-width:1200px;margin:0 auto;padding:0 24px}
.sl-mono{font-family:var(--sl-mono)}

/* Nút */
.sl-btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:10px 18px;border-radius:999px;border:1px solid transparent;font:inherit;font-size:14px;font-weight:700;line-height:1.2;cursor:pointer;transition:background .15s,border-color .15s,color .15s,transform .15s;white-space:nowrap}
.sl-btn-primary{background:var(--sl-grad);color:var(--sl-on-grad)}
.sl-btn-primary:hover{background:var(--sl-grad-h);color:var(--sl-on-grad)}
.sl-btn-ghost{background:#fff;border-color:var(--sl-border);color:var(--sl-ink-soft)}
.sl-btn-ghost:hover{border-color:#f0ad00;color:var(--sl-gold-d)}
.sl-btn-lg{padding:14px 26px;font-size:15.5px}
.sl-btn-block{width:100%}
.sl-btn:focus-visible,.sl a:focus-visible,.sl summary:focus-visible{outline:3px solid var(--sl-gold-bd);outline-offset:2px}

/* Thanh trên */
.sl-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.88);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border-bottom:1px solid var(--sl-border)}
.sl-nav{height:66px;display:flex;align-items:center;justify-content:space-between;gap:20px}
.sl-brand{display:flex;align-items:center;gap:10px}
.sl-logo{width:34px;height:34px;border-radius:10px;background:var(--sl-grad);display:flex;align-items:center;justify-content:center;flex-shrink:0}
.sl-logo svg{width:18px;height:18px;stroke:var(--sl-on-grad)}
.sl-brand-text{display:flex;flex-direction:column;line-height:1.15}
.sl-brand-name{font-size:16px;font-weight:800;letter-spacing:-.01em}
.sl-brand-tag{font-size:11.5px;color:var(--sl-faint);font-weight:500}
.sl-links{display:flex;align-items:center;gap:28px}
.sl-links a{display:inline-block;padding:8px 0;font-size:14px;font-weight:500;color:var(--sl-ink-soft)}
.sl-links a:hover{color:var(--sl-gold-d)}
.sl-actions{display:flex;align-items:center;gap:10px}
.sl-login{font-size:14px;font-weight:600;color:var(--sl-ink-soft);padding:9px 12px;border-radius:999px}
.sl-login:hover{color:var(--sl-gold-d)}

/* Hero */
.sl-hero-bg{background:radial-gradient(900px 420px at 85% 10%,rgba(255,215,0,.13),transparent 65%),radial-gradient(700px 380px at 0% 0%,rgba(255,165,0,.07),transparent 60%),#fff}
.sl-hero{padding:72px 24px 56px;display:grid;grid-template-columns:1.05fr 1fr;gap:56px;align-items:center}
.sl-pill{display:inline-flex;align-items:center;gap:8px;padding:6px 13px;background:var(--sl-gold-l);border:1px solid var(--sl-gold-bd);border-radius:999px;font-size:12.5px;font-weight:600;color:var(--sl-gold-d);margin-bottom:22px}
.sl-dot{width:6px;height:6px;border-radius:50%;background:var(--sl-gold);flex-shrink:0}
.sl-h1{font-size:48px;line-height:1.12;font-weight:800;letter-spacing:-.02em;margin-bottom:20px;text-wrap:balance}
.sl-accent{color:var(--sl-gold)}
.sl-lead{font-size:17.5px;line-height:1.65;color:var(--sl-muted);margin-bottom:30px;max-width:520px}
.sl-cta-row{display:flex;gap:12px;flex-wrap:wrap;margin-bottom:20px}
.sl-note{display:flex;align-items:center;gap:8px;font-size:13.5px;color:var(--sl-faint)}
.sl-note svg{stroke:var(--sl-gold);flex-shrink:0}

/* Thẻ mô phỏng app trong hero */
.sl-card{background:var(--sl-surface);border:1px solid var(--sl-border);border-radius:16px;box-shadow:0 1px 2px rgba(0,0,0,.03)}
.sl-demo{padding:20px;box-shadow:0 24px 60px -28px rgba(17,16,14,.28)}
.sl-demo-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:18px}
.sl-demo-title{font-size:13.5px;font-weight:700}
.sl-tag{display:inline-flex;align-items:center;gap:5px;padding:3px 9px;border-radius:999px;font-size:11.5px;font-weight:700;background:var(--sl-gold-l);color:var(--sl-gold-d)}
.sl-steps{display:flex;align-items:flex-start;margin-bottom:18px}
.sl-step{flex:1;position:relative;display:flex;flex-direction:column;align-items:center;gap:7px}
.sl-step::before,.sl-step::after{content:"";position:absolute;top:14px;height:2px;width:50%;background:var(--sl-border)}
.sl-step::before{left:0}.sl-step::after{right:0}
.sl-step:first-child::before,.sl-step:last-child::after{display:none}
.sl-step.is-done::before,.sl-step.is-done::after,.sl-step.is-now::before{background:var(--sl-gold)}
.sl-step-dot{width:28px;height:28px;border-radius:50%;display:flex;align-items:center;justify-content:center;position:relative;z-index:1;background:#fff;border:2px solid var(--sl-border)}
.sl-step.is-done .sl-step-dot{background:var(--sl-gold);border-color:var(--sl-gold)}
.sl-step.is-now .sl-step-dot{border-color:var(--sl-gold);box-shadow:0 0 0 4px var(--sl-gold-l)}
.sl-step.is-now .sl-step-dot span{width:8px;height:8px;border-radius:50%;background:var(--sl-gold)}
.sl-step-label{font-size:10px;color:var(--sl-muted);text-align:center;line-height:1.2}
.sl-step.is-now .sl-step-label{color:var(--sl-gold-d);font-weight:700}
.sl-demo-draft{border:1px solid var(--sl-border-2);border-radius:12px;padding:14px;margin-bottom:12px;background:var(--sl-surface-2)}
.sl-demo-draft b{display:block;font-size:13px;margin-bottom:8px}
.sl-line{height:7px;border-radius:4px;background:#e9e9eb;margin-top:7px}
.sl-cost{border:1px solid rgba(255,183,0,.35);border-radius:12px;padding:13px 14px;background:linear-gradient(135deg,#FFF9EA,#FFEFC9)}
.sl-cost-eyebrow{font-size:10.5px;font-weight:700;text-transform:uppercase;letter-spacing:.06em;color:#8a6a2a;margin-bottom:8px}
.sl-cost-row{display:flex;justify-content:space-between;font-size:13px;color:var(--sl-ink-soft)}
.sl-cost-row+.sl-cost-row{margin-top:6px}
.sl-cost-row b{font-family:var(--sl-mono);font-size:13.5px;color:var(--sl-ink)}

/* Khối chung */
.sl-section{padding:72px 24px}
.sl-soft{background:var(--sl-bg)}
.sl-eyebrow{font-size:12.5px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--sl-gold);margin-bottom:12px;text-align:center}
.sl-h2{text-align:center;font-size:34px;font-weight:800;letter-spacing:-.015em;margin-bottom:12px;text-wrap:balance}
.sl-sub{text-align:center;font-size:16px;color:var(--sl-muted);max-width:620px;margin:0 auto 40px}
.sl-grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.sl-feature{padding:26px}
.sl-icon{width:46px;height:46px;border-radius:12px;background:var(--sl-gold-l);border:1px solid var(--sl-gold-bd);display:flex;align-items:center;justify-content:center;margin-bottom:18px}
.sl-icon svg{stroke:var(--sl-gold-d)}
.sl-h3{font-size:18px;font-weight:700;margin-bottom:9px}
.sl-text{font-size:14.5px;line-height:1.65;color:var(--sl-muted)}

/* Quy trình — khối tối giống panel tối của app */
.sl-dark{background:var(--sl-dark);color:#f3efe9}
.sl-dark .sl-h2{color:#fff}
.sl-dark .sl-eyebrow{color:#ffc300}
.sl-steps-grid{list-style:none;display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.sl-step-card{background:var(--sl-dark-2);border:1px solid var(--sl-dark-bd);border-radius:16px;padding:24px}
.sl-step-card-head{display:flex;align-items:center;gap:12px;margin-bottom:12px}
.sl-step-no{width:38px;height:38px;border-radius:10px;background:rgba(255,195,0,.14);color:#ffc300;display:flex;align-items:center;justify-content:center;font-size:15px;font-weight:700;flex-shrink:0}
.sl-step-card h3{font-size:17px;font-weight:700;color:#fff}
.sl-step-card p{font-size:14px;line-height:1.6;color:#b9b0a6}

/* Bảng giá */
.sl-plans{align-items:start}
.sl-plan{padding:26px;position:relative}
.sl-plan.is-hot{border:2px solid #f0ad00;box-shadow:0 18px 44px -20px rgba(217,144,0,.45)}
.sl-plan-badge{position:absolute;top:16px;right:16px;padding:3px 10px;border-radius:999px;background:var(--sl-grad);color:var(--sl-on-grad);font-size:11.5px;font-weight:700}
.sl-plan h3{font-size:19px;font-weight:800;margin-bottom:14px}
.sl-price{display:flex;align-items:baseline;gap:5px;margin-bottom:4px}
.sl-price strong{font-size:34px;font-weight:800;letter-spacing:-.01em}
.sl-price span{font-size:14px;color:var(--sl-faint)}
.sl-plan-words{font-size:13px;color:var(--sl-muted);margin-bottom:20px}
.sl-plan-words b{color:var(--sl-gold-d)}

/* FAQ */
.sl-faq{max-width:840px;margin:0 auto}
.sl-faq-list{display:flex;flex-direction:column;gap:12px}
.sl-faq details{padding:4px 20px}
.sl-faq summary{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:16px 0;cursor:pointer;list-style:none;font-size:16px;font-weight:600}
.sl-faq summary::-webkit-details-marker{display:none}
.sl-faq summary svg{stroke:var(--sl-faint);flex-shrink:0;transition:transform .2s}
.sl-faq details[open] summary svg{transform:rotate(45deg);stroke:var(--sl-gold)}
.sl-faq details[open]{border-color:var(--sl-gold-bd)}
.sl-faq p{font-size:14.5px;line-height:1.7;color:var(--sl-muted);padding:0 0 18px}

/* CTA cuối */
.sl-final{padding:8px 24px 80px}
.sl-final-box{border-radius:22px;padding:56px 40px;text-align:center;background:radial-gradient(600px 260px at 50% 0%,rgba(255,215,0,.18),transparent 70%),var(--sl-dark)}
.sl-final-box h2{font-size:34px;font-weight:800;color:#fff;letter-spacing:-.015em;margin-bottom:14px;text-wrap:balance}
.sl-final-box p{font-size:16.5px;line-height:1.6;color:#c9c0b5;max-width:540px;margin:0 auto 28px}

/* Chân trang */
.sl-footer{background:#fff;border-top:1px solid var(--sl-border)}
.sl-footer-in{padding:32px 24px;display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.sl-footer-links{display:flex;gap:20px;flex-wrap:wrap;font-size:13.5px;color:var(--sl-muted)}
.sl-footer-links a{display:inline-block;padding:9px 0}
.sl-footer-links a:hover{color:var(--sl-gold-d)}
.sl-copy{font-size:12.5px;color:var(--sl-faint)}

@media (max-width:980px){
  .sl-hero{grid-template-columns:1fr;gap:40px;padding-top:48px}
  .sl-h1{font-size:40px}
}
@media (max-width:820px){
  .sl-links{display:none}
  .sl-grid3,.sl-steps-grid{grid-template-columns:1fr}
  .sl-section{padding:56px 16px}
  .sl-wrap{padding:0 16px}
  .sl-hero{padding:40px 16px 44px}
  .sl-final{padding:8px 16px 56px}
  .sl-footer-in{padding:28px 16px}
}
@media (max-width:520px){
  .sl-h1{font-size:32px}
  .sl-h2,.sl-final-box h2{font-size:27px}
  .sl-lead{font-size:16px}
  .sl-brand-tag,.sl-login{display:none}
  .sl-btn-lg{width:100%}
  .sl-final-box{padding:40px 22px}
  .sl-step-label{font-size:9px}
}
@media (prefers-reduced-motion:reduce){.sl *{transition:none!important}html{scroll-behavior:auto!important}}