/* © 2026 Panda Cyan. FEG Legend. */
/* FEG Legend - trang giới thiệu. Màu khai báo một chỗ; nền tối như app. */
:root {
  color-scheme: dark;
  --bg: #0a0e13;
  --bg-2: #0e141b;
  --surface: #121a23;
  --surface-2: #18222d;
  --line: #223140;
  --line-strong: #34495d;
  --ink: #eaf0f6;
  --ink-2: #c3cfdb;
  --ink-3: #93a5b8;
  --blue: #5aa7ff;
  --blue-strong: #3b8cf0;
  --mint: #2ee6a8;
  --mint-soft: rgba(46, 230, 168, 0.12);
  --blue-soft: rgba(90, 167, 255, 0.12);
  --warn: #f5c062;
  --warn-soft: rgba(245, 192, 98, 0.12);
  --on-accent: #04121f;
  --grad: linear-gradient(120deg, #5aa7ff 0%, #2ee6a8 100%);
  --radius: 14px;
  --radius-sm: 9px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
  --font: "Segoe UI", system-ui, -apple-system, Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: Consolas, "Cascadia Mono", ui-monospace, Menlo, monospace;
  --wrap: 1160px;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { transition: none !important; animation: none !important; } }
body {
  margin: 0; background: var(--bg); color: var(--ink); font-family: var(--font);
  font-size: 16px; line-height: 1.6; overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--blue); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: #8cc2ff; }
:focus-visible { outline: 2px solid var(--mint); outline-offset: 3px; border-radius: 6px; }
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 0.5em; letter-spacing: -0.01em; }
h1 { font-size: clamp(2rem, 5vw, 3.25rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(1.55rem, 3.2vw, 2.2rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; }
code, kbd { font-family: var(--mono); font-size: 0.92em; background: var(--surface-2); border: 1px solid var(--line); border-radius: 6px; padding: 0.05em 0.4em; }
.wrap { width: 100%; max-width: var(--wrap); margin: 0 auto; padding: 0 16px; }
@media (min-width: 768px) { .wrap { padding: 0 28px; } }
.muted { color: var(--ink-3); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.skip { position: absolute; left: 12px; top: -60px; background: var(--mint); color: var(--on-accent); padding: 8px 14px; border-radius: 8px; z-index: 100; font-weight: 600; }
.skip:focus { top: 12px; }
.grad-text { background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
[hidden] { display: none !important; }

/* Nút */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 44px; padding: 10px 18px; border-radius: 10px; border: 1px solid transparent;
  font: inherit; font-weight: 600; text-decoration: none; cursor: pointer; line-height: 1.2;
  transition: transform 0.15s ease, background-color 0.15s ease, border-color 0.15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn svg { width: 18px; height: 18px; flex: none; }
.btn-primary { background: var(--grad); color: var(--on-accent); }
.btn-primary:hover { color: var(--on-accent); filter: brightness(1.06); }
.btn-ghost { background: var(--surface); color: var(--ink); border-color: var(--line-strong); }
.btn-ghost:hover { color: var(--ink); border-color: var(--blue); }
.btn-small { min-height: 36px; padding: 6px 12px; font-size: 0.93rem; }
.btn[aria-disabled="true"] { opacity: 0.55; pointer-events: none; }

/* Đầu trang */
.site-header { position: sticky; top: 0; z-index: 50; background: rgba(10, 14, 19, 0.86); backdrop-filter: blur(12px); border-bottom: 1px solid var(--line); }
.site-header .wrap { display: flex; align-items: center; gap: 16px; min-height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none; font-weight: 700; font-size: 1.08rem; margin-right: auto; }
.brand:hover { color: var(--ink); }
.brand img { width: 32px; height: 32px; }
.nav { display: flex; align-items: center; gap: 4px; }
.nav a { color: var(--ink-2); text-decoration: none; padding: 8px 12px; border-radius: 8px; font-weight: 500; }
.nav a:hover { color: var(--ink); background: var(--surface); }
.nav a[aria-current="page"] { color: var(--ink); background: var(--surface-2); }
.nav .btn { margin-left: 8px; color: var(--on-accent); }
.nav-toggle { display: none; background: var(--surface); color: var(--ink); border: 1px solid var(--line-strong); border-radius: 10px; width: 44px; height: 44px; cursor: pointer; }
.nav-toggle svg { width: 22px; height: 22px; }
@media (max-width: 899px) {
  .nav-toggle { display: inline-flex; align-items: center; justify-content: center; }
  .nav { display: none; position: absolute; left: 0; right: 0; top: 64px; flex-direction: column; align-items: stretch; gap: 2px; padding: 10px 16px 16px; background: var(--bg-2); border-bottom: 1px solid var(--line); box-shadow: var(--shadow); }
  .nav.open { display: flex; }
  .nav a { padding: 12px 12px; }
  .nav .btn { margin: 8px 0 0; }
}

/* Khối chung */
section { padding: 72px 0; }
@media (max-width: 767px) { section { padding: 52px 0; } }
.section-alt { background: var(--bg-2); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { max-width: 720px; margin: 0 auto 40px; text-align: center; }
.section-head p { color: var(--ink-3); font-size: 1.05rem; }
.eyebrow { display: inline-block; font-size: 0.82rem; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; color: var(--mint); margin-bottom: 10px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.grid { display: grid; gap: 18px; }
@media (min-width: 640px) { .grid-2 { grid-template-columns: repeat(2, 1fr); } .grid-3 { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .grid-3 { grid-template-columns: repeat(3, 1fr); } }
@media (min-width: 640px) { .grid-4 { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .grid-4 { grid-template-columns: repeat(4, 1fr); } }
.contact-card { display: flex; flex-direction: column; }
.contact-card h3 { margin-bottom: 8px; }
.contact-card p { color: var(--ink-3); margin: 0 0 16px; flex: 1; }
.contact-card .btn { align-self: flex-start; }
.hero-community { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 18px 0 22px; color: var(--ink-3); font-size: 0.95rem; }
.hero-community .pill { display: inline-flex; align-items: center; min-height: 34px; padding: 4px 14px; border-radius: 999px; border: 1px solid var(--mint); background: var(--mint-soft); color: var(--mint); text-decoration: none; font-weight: 600; }
.hero-community .pill:hover { background: var(--mint); color: var(--bg); }
.hero-community[hidden], .contact-card[hidden] { display: none; }
.icon { width: 44px; height: 44px; border-radius: 12px; display: inline-flex; align-items: center; justify-content: center; background: var(--blue-soft); color: var(--blue); margin-bottom: 14px; }
.icon svg { width: 24px; height: 24px; }
.icon.mint { background: var(--mint-soft); color: var(--mint); }
.icon.warn { background: var(--warn-soft); color: var(--warn); }
.check-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.check-list li { position: relative; padding-left: 28px; color: var(--ink-2); }
.check-list li::before { content: ""; position: absolute; left: 2px; top: 0.45em; width: 14px; height: 8px; border-left: 2px solid var(--mint); border-bottom: 2px solid var(--mint); transform: rotate(-45deg); }

/* Mở đầu */
.hero { padding: 64px 0 56px; position: relative; overflow: hidden; }
.hero::before { content: ""; position: absolute; inset: -40% -20% auto auto; width: 70%; height: 120%; background: radial-gradient(closest-side, rgba(90, 167, 255, 0.18), transparent); pointer-events: none; }
.hero::after { content: ""; position: absolute; inset: auto auto -50% -20%; width: 60%; height: 100%; background: radial-gradient(closest-side, rgba(46, 230, 168, 0.1), transparent); pointer-events: none; }
.hero .wrap { position: relative; z-index: 1; display: grid; gap: 40px; align-items: center; }
@media (min-width: 1000px) { .hero .wrap { grid-template-columns: 1fr 1.15fr; } .hero { padding: 88px 0 80px; } }
.hero-lead { font-size: 1.15rem; color: var(--ink-2); max-width: 560px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 26px 0 22px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; padding: 0; margin: 0; }
.chips li { font-size: 0.88rem; color: var(--ink-2); background: var(--surface); border: 1px solid var(--line); border-radius: 999px; padding: 5px 12px; }
.badge { display: inline-flex; align-items: center; gap: 8px; font-size: 0.86rem; font-weight: 600; color: var(--mint); background: var(--mint-soft); border: 1px solid rgba(46, 230, 168, 0.3); padding: 5px 12px; border-radius: 999px; margin-bottom: 18px; }
.badge .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--mint); }
.shot { margin: 0; border-radius: 14px; border: 1px solid var(--line-strong); background: var(--surface); box-shadow: var(--shadow); overflow: hidden; }
.shot-bar { display: flex; align-items: center; gap: 7px; padding: 10px 14px; border-bottom: 1px solid var(--line); background: var(--surface-2); }
.shot-bar span { width: 10px; height: 10px; border-radius: 50%; background: var(--line-strong); }
.shot-bar b { margin-left: 8px; font-weight: 500; font-size: 0.82rem; color: var(--ink-3); }
.shot figcaption { font-size: 0.85rem; color: var(--ink-3); padding: 10px 14px; border-top: 1px solid var(--line); }

/* Tính năng */
.feature h3 { margin-bottom: 8px; }
.feature p { color: var(--ink-3); margin: 0 0 12px; }
.feature ul { margin: 0; padding-left: 18px; color: var(--ink-2); font-size: 0.95rem; }
.feature li + li { margin-top: 4px; }

/* Tải về */
.download { display: grid; gap: 28px; align-items: start; background: linear-gradient(150deg, rgba(90, 167, 255, 0.1), rgba(46, 230, 168, 0.06)), var(--surface); border-color: var(--line-strong); padding: 32px; }
@media (min-width: 900px) { .download { grid-template-columns: 1.1fr 1fr; padding: 40px; } }
.release-meta { display: grid; grid-template-columns: repeat(auto-fit, minmax(110px, 1fr)); gap: 10px; margin: 20px 0 24px; }
.release-meta div { background: var(--bg-2); border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 10px 12px; min-width: 0; }
.release-meta dt { font-size: 0.8rem; color: var(--ink-3); }
.release-meta dd { margin: 2px 0 0; font-weight: 700; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.release-note { font-size: 0.92rem; color: var(--ink-3); margin-top: 12px; }
.notice { border-radius: var(--radius-sm); padding: 12px 14px; background: var(--warn-soft); border: 1px solid rgba(245, 192, 98, 0.35); color: var(--ink); font-size: 0.95rem; }
.notice.info { background: var(--blue-soft); border-color: rgba(90, 167, 255, 0.35); }

/* Các bước */
.steps { counter-reset: step; list-style: none; padding: 0; margin: 0; }
.steps > li { counter-increment: step; position: relative; }
.steps.grid > li { padding-top: 72px; }
.steps.grid > li::before { content: counter(step); position: absolute; top: 20px; left: 24px; width: 34px; height: 34px; border-radius: 10px; background: var(--grad); color: var(--on-accent); font-weight: 800; display: flex; align-items: center; justify-content: center; }
.steps h3 { margin-bottom: 6px; }
.steps p { color: var(--ink-3); margin: 0; }

/* Bảng giá */
.plans { display: grid; gap: 18px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); align-items: stretch; }
.plan { display: flex; flex-direction: column; position: relative; }
.plan.highlight { border-color: var(--mint); box-shadow: 0 0 0 1px var(--mint), var(--shadow); }
.plan-tag { position: absolute; top: -12px; left: 24px; background: var(--grad); color: var(--on-accent); font-size: 0.78rem; font-weight: 700; padding: 3px 10px; border-radius: 999px; }
.plan-price { font-size: 2rem; font-weight: 800; margin: 6px 0 2px; overflow-wrap: anywhere; }
.plan-period { color: var(--ink-3); margin-bottom: 16px; }
.plan .check-list { margin-bottom: 20px; }
.plan .btn { margin-top: auto; }
.plan-note { font-size: 0.88rem; color: var(--ink-3); margin: 10px 0 0; }
.quote-card { max-width: 720px; margin: 0 auto; text-align: center; padding: 36px 28px; }
.quote-card p { color: var(--ink-2); }
.contact-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin-top: 18px; }

/* Hỏi đáp và mục mở rộng */
.faq { max-width: 820px; margin: 0 auto; display: grid; gap: 10px; }
details.fold { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-sm); }
details.fold > summary { list-style: none; cursor: pointer; padding: 16px 48px 16px 18px; font-weight: 600; position: relative; }
details.fold > summary::-webkit-details-marker { display: none; }
details.fold > summary::after { content: ""; position: absolute; right: 20px; top: 50%; width: 9px; height: 9px; border-right: 2px solid var(--ink-3); border-bottom: 2px solid var(--ink-3); transform: translateY(-70%) rotate(45deg); transition: transform 0.2s ease; }
details.fold[open] > summary::after { transform: translateY(-30%) rotate(-135deg); }
details.fold > summary:hover { color: var(--blue); }
details.fold .fold-body { padding: 0 18px 18px; color: var(--ink-2); }
details.fold .fold-body p:last-child { margin-bottom: 0; }

/* Chân trang */
.site-footer { border-top: 1px solid var(--line); background: var(--bg-2); padding: 48px 0 28px; font-size: 0.95rem; }
.footer-grid { display: grid; gap: 28px; }
@media (min-width: 768px) { .footer-grid { grid-template-columns: 1.6fr 1fr 1fr; } }
.site-footer h2 { font-size: 0.95rem; color: var(--ink); margin-bottom: 12px; }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 6px; }
.site-footer a { color: var(--ink-3); text-decoration: none; }
.site-footer a:hover { color: var(--ink); text-decoration: underline; }
.footer-bottom { margin-top: 32px; padding-top: 18px; border-top: 1px solid var(--line); color: var(--ink-3); font-size: 0.85rem; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 8px; }

/* Trang hướng dẫn */
.page-hero { padding: 56px 0 36px; border-bottom: 1px solid var(--line); background: radial-gradient(60% 120% at 80% 0%, rgba(90, 167, 255, 0.12), transparent), var(--bg); }
.page-hero p { color: var(--ink-2); max-width: 720px; font-size: 1.08rem; }
.toc { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; list-style: none; padding: 0; }
.toc a { display: inline-block; padding: 7px 14px; border-radius: 999px; background: var(--surface); border: 1px solid var(--line); color: var(--ink-2); text-decoration: none; font-size: 0.93rem; }
.toc a:hover { border-color: var(--blue); color: var(--ink); }
.guide-section { padding: 56px 0; scroll-margin-top: 72px; }
.guide-section + .guide-section { border-top: 1px solid var(--line); }
.guide-section > .wrap > p.lead { color: var(--ink-3); max-width: 760px; }
.how-list { counter-reset: how; list-style: none; padding: 0; margin: 20px 0 0; display: grid; gap: 14px; }
.how-list > li { counter-increment: how; position: relative; padding: 18px 20px 18px 66px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-sm); }
.how-list > li::before { content: counter(how); position: absolute; left: 18px; top: 18px; width: 32px; height: 32px; border-radius: 9px; background: var(--blue-soft); color: var(--blue); font-weight: 800; display: flex; align-items: center; justify-content: center; }
.how-list h3 { font-size: 1.05rem; margin-bottom: 4px; }
.how-list p { color: var(--ink-3); margin: 0; }
.how-list p + p { margin-top: 8px; }
.req-table { width: 100%; border-collapse: collapse; margin-top: 18px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-sm); overflow: hidden; }
.req-table th, .req-table td { text-align: left; padding: 12px 16px; border-bottom: 1px solid var(--line); vertical-align: top; }
.req-table th { width: 34%; color: var(--ink-2); font-weight: 600; background: var(--surface-2); }
.req-table tr:last-child th, .req-table tr:last-child td { border-bottom: 0; }
@media (max-width: 599px) { .req-table th, .req-table td { display: block; width: 100%; } .req-table th { border-bottom: 0; padding-bottom: 4px; } .req-table td { padding-top: 0; } }
.mode-grid { margin-top: 20px; }
.filters { display: flex; flex-wrap: wrap; gap: 8px; margin: 20px 0; align-items: center; }
.filter-btn { font: inherit; font-size: 0.93rem; min-height: 38px; padding: 6px 14px; border-radius: 999px; border: 1px solid var(--line-strong); background: var(--surface); color: var(--ink-2); cursor: pointer; }
.filter-btn:hover { color: var(--ink); border-color: var(--blue); }
.filter-btn[aria-pressed="true"] { background: var(--blue-soft); border-color: var(--blue); color: var(--ink); }
.filters .spacer { flex: 1; }
.handbook { display: grid; gap: 12px; }
.hb-title { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.tag { font-size: 0.75rem; font-weight: 700; padding: 2px 9px; border-radius: 999px; background: var(--blue-soft); color: var(--blue); }
.tag.mint { background: var(--mint-soft); color: var(--mint); }
.tag.warn { background: var(--warn-soft); color: var(--warn); }
.hb-body ul { padding-left: 20px; margin: 0 0 14px; }
.hb-body li + li { margin-top: 6px; }
.tip { border-left: 3px solid var(--mint); background: var(--mint-soft); padding: 10px 14px; border-radius: 0 8px 8px 0; color: var(--ink); }
.tip strong { color: var(--mint); }
.video { margin: 0 0 16px; }
.video-frame { position: relative; aspect-ratio: 16 / 9; border-radius: var(--radius-sm); overflow: hidden; background: #000; border: 1px solid var(--line); }
.video-frame iframe, .video-frame img { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; object-fit: cover; }
.video-play { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; padding: 0; background: transparent; cursor: pointer; }
.video-play span { position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%); background: var(--grad); color: var(--on-accent); font-weight: 700; padding: 10px 18px; border-radius: 999px; }
.video-list { margin-top: 20px; }
.video-card h3 { font-size: 1rem; margin: 12px 0 0; }

/* Trang cập nhật */
.timeline { list-style: none; padding: 0; margin: 0; position: relative; max-width: 860px; }
.timeline::before { content: ""; position: absolute; left: 11px; top: 8px; bottom: 8px; width: 2px; background: var(--line); }
.timeline > li { position: relative; padding-left: 44px; margin-bottom: 22px; }
.timeline > li::before { content: ""; position: absolute; left: 4px; top: 24px; width: 16px; height: 16px; border-radius: 50%; background: var(--bg); border: 3px solid var(--line-strong); }
.timeline > li.latest::before { border-color: var(--mint); box-shadow: 0 0 0 4px var(--mint-soft); }
.rel-head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 14px; margin-bottom: 10px; }
.rel-head h2 { font-size: 1.35rem; margin: 0; }
.rel-head .when { color: var(--ink-3); font-size: 0.93rem; }
.rel-notes { color: var(--ink-2); }
.rel-notes h3 { font-size: 0.95rem; color: var(--ink); margin: 14px 0 6px; }
.rel-notes ul { margin: 0 0 8px; padding-left: 20px; }
.rel-notes p { margin: 0 0 8px; white-space: pre-wrap; overflow-wrap: anywhere; }
.rel-foot { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 14px; color: var(--ink-3); font-size: 0.9rem; }
.empty { text-align: center; padding: 48px 24px; max-width: 640px; margin: 0 auto; }
.empty p { color: var(--ink-3); }
.hero h1 { font-size: clamp(2rem, 4.4vw, 2.85rem); }
.hero h1 .line { display: block; }
.center { text-align: center; }
.site-footer .brand, .site-footer .brand:hover { color: var(--ink); text-decoration: none; }
.guide-section .faq { margin: 20px 0 0; }
.rel-notes ul, .fold-body ul { list-style: disc; }
@media (max-width: 599px) { .download { padding: 24px 20px; } }
[data-video] .video { max-width: 640px; margin-top: 16px; }
details.fold, [id] { scroll-margin-top: 80px; }