/* ===== IELTS 8020 — design system dùng chung (màu lấy từ logo: navy #1C355F · hồng #ED0E57) ===== */
:root {
  --navy:#1C355F; --navy-2:#274B85; --pink:#ED0E57; --pink-soft:#FFF0F5;
  --bg:#F7F9FC; --card:#FFFFFF; --line:#E5E7EB; --muted:#6B7280; --text:#1F2937;
  --ok:#065F46; --okbg:#D1FAE5; --warn:#B45309; --warnbg:#FEF3E2;
  --radius:14px; --shadow:0 1px 3px rgba(16,24,40,.07);
}
* { box-sizing:border-box; margin:0; }
html { scroll-behavior:smooth; }
body { font-family:system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif; background:var(--bg); color:var(--text); line-height:1.6; }
img { max-width:100%; }
a { color:var(--navy-2); }
.wrap { max-width:1080px; margin:0 auto; padding:0 20px; }

/* ===== Header 2 tầng kiểu YouPass: hàng logo → thanh tab lớn → hàng tab con ===== */
.site-header { background:#fff; border-bottom:1px solid var(--line); position:sticky; top:0; z-index:50; }
.site-header .top-row { display:flex; align-items:center; gap:20px; height:58px; }
.site-logo { display:flex; align-items:center; gap:9px; text-decoration:none; flex:none; }
.site-logo img { height:36px; }
.site-logo span { font-weight:800; color:var(--navy); font-size:15px; letter-spacing:.2px; }
.tabbar { background:var(--pink-soft); border-top:1px solid #FBD9E5; }
.main-nav { display:flex; gap:2px; overflow-x:auto; scrollbar-width:none; }
.main-nav::-webkit-scrollbar { display:none; }
.main-nav a { text-decoration:none; color:#4B5563; font-size:14px; font-weight:700; padding:11px 14px; white-space:nowrap; border-bottom:3px solid transparent; }
.main-nav a .t-emo { margin-right:2px; }
.main-nav a:hover { color:var(--navy); background:rgba(255,255,255,.6); }
.main-nav a.active { color:var(--pink); background:#fff; border-bottom-color:var(--pink); }
.subbar { background:#fff; border-top:1px solid var(--line); }
.subbar .wrap { display:flex; gap:4px; overflow-x:auto; scrollbar-width:none; }
.subbar .wrap::-webkit-scrollbar { display:none; }
.subbar a { text-decoration:none; color:var(--muted); font-size:13px; font-weight:600; padding:9px 12px; white-space:nowrap; }
.subbar a:hover { color:var(--pink); }
.header-cta { margin-left:auto; display:flex; gap:9px; align-items:center; }
.btn { display:inline-block; border:0; border-radius:10px; padding:10px 20px; font-size:14.5px; font-weight:700; cursor:pointer; text-decoration:none; text-align:center; }
.btn-pink { background:var(--pink); color:#fff; }
.btn-pink:hover { background:#D00A4C; }
.btn-navy { background:var(--navy); color:#fff; }
.btn-outline { background:#fff; color:var(--navy); border:1.5px solid var(--line); }
.btn-outline:hover { border-color:var(--navy); }
.btn-lg { padding:14px 28px; font-size:16px; border-radius:12px; }
.nav-toggle { display:none; margin-left:auto; background:none; border:0; font-size:24px; cursor:pointer; color:var(--navy); }

/* ===== Sections ===== */
.section { padding:64px 0; }
.section.alt { background:#fff; }
.kicker { color:var(--pink); font-weight:800; font-size:13px; text-transform:uppercase; letter-spacing:1.2px; margin-bottom:10px; }
h1.hero-title { color:var(--navy); font-size:clamp(30px,4.6vw,46px); line-height:1.18; letter-spacing:-.5px; }
h2.sec-title { color:var(--navy); font-size:clamp(23px,3vw,32px); line-height:1.25; margin-bottom:10px; }
.sec-lead { color:var(--muted); font-size:16.5px; max-width:640px; }
.center { text-align:center; }
.center .sec-lead { margin:0 auto; }

/* ===== Cards ===== */
.grid { display:grid; gap:18px; }
.grid.c2 { grid-template-columns:repeat(auto-fit,minmax(320px,1fr)); }
.grid.c3 { grid-template-columns:repeat(auto-fit,minmax(250px,1fr)); }
.grid.c4 { grid-template-columns:repeat(auto-fit,minmax(210px,1fr)); }
.card { background:var(--card); border:1px solid var(--line); border-radius:var(--radius); padding:24px; box-shadow:var(--shadow); }
.card h3 { color:var(--navy); font-size:17px; margin-bottom:8px; }
.card p { color:var(--muted); font-size:14.5px; }
.card .emoji { font-size:30px; margin-bottom:12px; display:block; }
ul.checks { list-style:none; margin:14px 0 0; }
ul.checks li { padding-left:26px; position:relative; margin-bottom:9px; font-size:14.5px; }
ul.checks li::before { content:"✓"; position:absolute; left:2px; color:var(--pink); font-weight:800; }

/* ===== Pill / badge ===== */
.pill { display:inline-block; border-radius:999px; padding:4px 13px; font-size:12.5px; font-weight:700; }
.pill.free { background:var(--okbg); color:var(--ok); }
.pill.pro { background:var(--pink-soft); color:var(--pink); }
.pill.soon { background:#EEF2F7; color:var(--muted); }
.pill.hot { background:var(--warnbg); color:var(--warn); }

/* ===== Footer ===== */
.site-footer { background:var(--navy); color:#C7D2E4; padding:44px 0 26px; margin-top:64px; }
.site-footer a { color:#fff; text-decoration:none; }
.site-footer a:hover { text-decoration:underline; }
.foot-grid { display:grid; grid-template-columns:2fr 1fr 1fr; gap:28px; margin-bottom:26px; }
.foot-grid h4 { color:#fff; font-size:14px; margin-bottom:12px; text-transform:uppercase; letter-spacing:.8px; }
.foot-grid li { list-style:none; margin-bottom:8px; font-size:14px; }
.foot-brand img { height:44px; background:#fff; border-radius:10px; padding:5px 10px; margin-bottom:12px; }
.foot-bottom { border-top:1px solid rgba(255,255,255,.15); padding-top:18px; font-size:13px; display:flex; justify-content:space-between; flex-wrap:wrap; gap:8px; }

/* ===== Test cards (hub luyện tập) ===== */
.test-card { background:#fff; border:1px solid var(--line); border-radius:var(--radius); padding:20px; display:flex; flex-direction:column; gap:9px; box-shadow:var(--shadow); }
.test-card .tag-row { display:flex; gap:7px; flex-wrap:wrap; }
.test-card h3 { color:var(--navy); font-size:16px; line-height:1.4; }
.test-card .meta { color:var(--muted); font-size:13px; }
.test-card .btn { margin-top:auto; }
.filter-row { display:flex; gap:8px; flex-wrap:wrap; margin:20px 0 22px; }
.filter-chip { border:1.5px solid var(--line); background:#fff; border-radius:999px; padding:7px 16px; font-size:13.5px; font-weight:600; cursor:pointer; color:#374151; }
.filter-chip.active { background:var(--navy); border-color:var(--navy); color:#fff; }
.skill-tabs { display:flex; gap:6px; border-bottom:2px solid var(--line); margin-bottom:4px; overflow-x:auto; }
.skill-tab { border:0; background:none; padding:12px 20px; font-size:15.5px; font-weight:700; color:var(--muted); cursor:pointer; border-bottom:3px solid transparent; margin-bottom:-2px; white-space:nowrap; }
.skill-tab.active { color:var(--pink); border-bottom-color:var(--pink); }

/* ===== Certs carousel ===== */
.certs-strip { display:flex; gap:16px; overflow-x:auto; padding:6px 2px 16px; scroll-snap-type:x mandatory; }
.certs-strip img { height:340px; border-radius:12px; border:1px solid var(--line); box-shadow:var(--shadow); scroll-snap-align:start; cursor:zoom-in; }
.cert-note { color:var(--muted); font-size:13px; margin-top:4px; }

/* ===== Quy tắc 8020 ===== */
.pareto { display:flex; align-items:center; gap:34px; }
.pareto-viz { flex:none; width:230px; }
.pareto-bar { display:flex; height:56px; border-radius:12px; overflow:hidden; font-weight:800; color:#fff; font-size:15px; }
.pareto-bar .p20 { background:var(--pink); width:20%; display:flex; align-items:center; justify-content:center; }
.pareto-bar .p80 { background:var(--navy); width:80%; display:flex; align-items:center; justify-content:center; }
.pareto-lab { display:flex; justify-content:space-between; font-size:12px; color:var(--muted); margin-top:7px; }

/* ===== Lightbox ===== */
.lightbox { position:fixed; inset:0; background:rgba(10,15,30,.86); display:flex; align-items:center; justify-content:center; z-index:200; cursor:zoom-out; }
.lightbox img { max-height:92vh; max-width:92vw; border-radius:10px; }

/* ===== FAQ ===== */
details.faq { background:#fff; border:1px solid var(--line); border-radius:12px; padding:16px 20px; margin-bottom:10px; }
details.faq summary { font-weight:700; color:var(--navy); cursor:pointer; font-size:15px; }
details.faq p { margin-top:10px; color:#374151; font-size:14.5px; }

@media (max-width:760px) {
  /* Mobile: thanh tab lớn vẫn hiện, cuộn ngang được (giống app) — nút ☰ chỉ mở nhanh */
  .header-cta { display:none; }
  .nav-toggle { display:block; }
  .main-nav a { padding:10px 10px; font-size:13px; }
  .foot-grid { grid-template-columns:1fr; }
  .pareto { flex-direction:column; align-items:flex-start; }
  .section { padding:44px 0; }
}