/* Hallmark · macrostructure: Catalogue · tone: modern-minimal · anchor hue: blue
 * Theme: Apple-inspired, per brief · nav: N9 · footer: Ft2
 * Pre-emit critique: P4 H4 E4 S4 R5 V4
 * Biến thiết kế được quản lý tập trung trong :root. */
:root {
  --color-paper: #f5f5f7;
  --color-surface: #ffffff;
  --color-ink: #1d1d1f;
  --color-muted: #68686e;
  --color-accent: #0066cc;
  --color-accent-hover: #0055ad;
  --color-accent-ink: #ffffff;
  --color-rule: #dedee3;
  --color-control-border: #d2d2d7;
  --color-filter: #e9e9ed;
  --color-badge: #ffffffed;
  --color-shadow: #1d1d1f09;
  --color-shadow-hover: #1d1d1f12;
  --color-language-shadow: oklch(20% 0.008 265 / 0.08);
  --color-header-ink: oklch(20% 0.008 265);
  --color-header-muted: oklch(44% 0.008 265);
  --color-header-accent: oklch(45% 0.12 256);
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, sans-serif;
  --font-header: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  --page-width: 70rem;
  --page-gutter: 2.5rem;
  --radius-card: 24px;
  --language-switch-gap: 4px;
  --language-switch-padding: 4px;
  --language-switch-radius: 14px;
  --language-switch-item-radius: 6px;
  --language-switch-selected-radius: 10px;
  --space-2xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;
  --text-xs: 13px;
  --text-lead: 18px;
  --text-statement: clamp(32px, 4.5vw, 60px);
  --ease-out: cubic-bezier(.22, 1, .36, 1);
  --dur-fast: 180ms;
}

/* 1. Nền tảng và hỗ trợ bàn phím */
* { box-sizing: border-box; }
html { overflow-x: clip; scroll-padding-top: 24px; scroll-behavior: smooth; }
body { margin: 0; overflow-x: clip; background: var(--color-paper); color: var(--color-ink); font-family: var(--font-body); -webkit-font-smoothing: antialiased; line-height: 1.6; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }
a { color: inherit; text-decoration: none; }
button, .contact-link, .product-actions a, .email-link { white-space: nowrap; }
button { cursor: pointer; }
img { max-width: 100%; display: block; }
h1, h2, h3, p { margin: 0; }
h1, h2, h3 { min-width: 0; overflow-wrap: anywhere; }
[hidden] { display: none !important; }
a:focus-visible, button:focus-visible { outline: 3px solid var(--color-accent); outline-offset: 5px; }
.container { width: min(calc(100% - var(--page-gutter)), var(--page-width)); margin-inline: auto; }
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.skip-link { position: fixed; top: 12px; left: 16px; z-index: 10; padding: 12px 20px; background: var(--color-surface); border-radius: 8px; transform: translateY(-160%); }
.skip-link:focus { transform: translateY(0); }

/* 2. Header và phần giới thiệu */
.site-header { display: flex; align-items: center; min-height: 100px; gap: var(--space-lg); color: var(--color-header-ink); font-family: var(--font-header); }
.brand { display: inline-flex; align-items: center; min-height: 44px; font-size: 1rem; font-weight: 700; line-height: 1.6; letter-spacing: -.04em; white-space: nowrap; }
.brand-link { display: inline-flex; align-items: center; min-height: 44px; color: inherit; text-decoration: none; }
.brand-link:active { color: var(--color-header-accent); }
.brand-link:focus-visible { outline: 2px solid var(--color-header-accent); outline-offset: 4px; border-radius: 8px; }
.brand-mark { display: grid; place-items: center; width: 34px; height: 34px; margin-right: 10px; border-radius: 10px; background: var(--color-ink); color: var(--color-surface); font-size: 25px; line-height: 1; padding-bottom: 4px; }
.brand-name { color: var(--color-header-ink); font-weight: inherit; }
.brand-suffix { margin-left: var(--space-2xs); color: var(--color-header-muted); font-size: inherit; font-weight: 400; letter-spacing: -.02em; }
.header-nav { display: flex; margin-left: auto; }
.contact-link { display: inline-flex; align-items: center; gap: 12px; min-height: 44px; font-size: 14px; cursor: pointer; }
.contact-link > span[aria-hidden="true"] { display: inline-block; transition: transform var(--dur-fast) var(--ease-out); }
.contact-link:hover > span[aria-hidden="true"] { transform: translate(2px, -2px); }
.contact-link:active { color: var(--color-header-accent); }
.email-link:hover { color: var(--color-accent); }
.contact-link:focus-visible { outline: 2px solid var(--color-header-accent); outline-offset: 4px; border-radius: 8px; }
.hero { padding: 64px 0 88px; text-align: center; }
.hero-label { color: var(--color-muted); font-size: 14px; margin-bottom: 20px; }
h1 { font-size: clamp(40px, 5.5vw, 68px); line-height: 1.14; letter-spacing: -.055em; font-weight: 650; }
.hero-description { margin: 24px auto 0; color: var(--color-muted); font-size: 17px; line-height: 1.75; max-width: 570px; }

/* 3. Bộ lọc và lưới; minmax tránh tràn khi ảnh có kích thước lớn */
.collection-toolbar { display: flex; align-items: center; justify-content: space-between; gap: var(--space-md); margin-bottom: 28px; }
.filters { display: flex; align-items: center; padding: 5px; gap: 4px; background: var(--color-filter); border-radius: 14px; }
.filter-button { border: 0; border-radius: 10px; min-height: 44px; padding: 10px 20px; background: transparent; color: var(--color-muted); font-size: 13px; font-weight: 550; }
.filter-button:hover { color: var(--color-ink); }
.filter-button[aria-pressed="true"] { background: var(--color-surface); color: var(--color-ink); box-shadow: 0 2px 6px var(--color-shadow); }
.filter-count { margin-left: 6px; font-size: 11px; color: var(--color-muted); }
.result-count { color: var(--color-muted); font-size: 13px; }
.product-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px; }
.product-card { min-width: 0; overflow: hidden; display: flex; flex-direction: column; border-radius: var(--radius-card); background: var(--color-surface); box-shadow: 0 4px 20px var(--color-shadow); transition: transform 240ms var(--ease-out); }
@media (hover: hover) { .product-card:hover { transform: translateY(-4px); box-shadow: 0 12px 28px var(--color-shadow-hover); } }
.product-visual { position: relative; aspect-ratio: 8 / 5; background: var(--color-filter); overflow: hidden; }
.product-screenshot { width: 100%; height: 100%; object-fit: cover; }
.category-label { position: absolute; top: 20px; left: 20px; background: var(--color-badge); color: var(--color-ink); font-size: 10px; font-weight: 650; letter-spacing: .06em; text-transform: uppercase; padding: 5px 10px; border-radius: 6px; }
.product-content { padding: 28px 30px 30px; display: flex; flex-direction: column; flex-grow: 1; }
.product-heading { display: flex; align-items: center; gap: 14px; min-height: 56px; }
.app-icon { flex-shrink: 0; border-radius: 13px; background: var(--color-paper); }
.product-type { color: var(--color-muted); font-size: 11px; margin-bottom: 1px; }
.product-name { font-size: 24px; font-weight: 650; letter-spacing: -.7px; line-height: 1.35; }
.product-description { font-size: 14px; color: var(--color-muted); line-height: 1.75; margin: 16px 0 24px; }
.product-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-top: auto; }
.website-button { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; gap: 20px; background: var(--color-accent); color: var(--color-accent-ink); border-radius: 10px; padding: 10px 17px; font-size: 13px; font-weight: 550; }
.website-button:hover { background: var(--color-accent-hover); }
.product-actions a:active { transform: translateY(1px); }
.store-button { display: inline-flex; align-items: center; gap: 8px; min-height: 44px; padding: 8px 13px; border: 1px solid var(--color-rule); border-radius: 10px; font-size: 12px; font-weight: 600; }
.store-button:hover { background: var(--color-paper); border-color: var(--color-muted); }
.store-button img { width: 18px; height: 20px; }
.sample-note { text-align: center; color: var(--color-muted); font-size: 12px; margin: 32px 0 64px; }
.empty-state { text-align: center; padding: 48px 20px; color: var(--color-muted); grid-column: 1 / -1; }

/* 4. Footer */
.site-footer { padding-block: var(--space-3xl) var(--space-xl); border-top: 1px solid var(--color-rule); }
#contact:focus { outline: none; }
.site-footer h2 { font-size: var(--text-statement); font-weight: 700; line-height: 1.2; letter-spacing: -.055em; }
.site-footer > p { margin-top: var(--space-lg); color: var(--color-muted); }
.footer-text-link { display: inline-flex; align-items: center; justify-content: space-between; gap: var(--space-sm); min-height: 44px; font-weight: 500; text-underline-offset: 5px; }
.email-link { margin-top: var(--space-lg); font-size: var(--text-lead); }
.footer-bottom { display: flex; justify-content: space-between; align-items: center; gap: var(--space-lg); margin-top: var(--space-4xl); color: var(--color-muted); font-size: var(--text-xs); }
.footer-bottom .footer-text-link { font-size: var(--text-xs); }
@media (hover: hover) { .footer-text-link:hover { text-decoration: underline; } }

/* 5. Tablet, mobile và tùy chọn giảm chuyển động */
@media (max-width: 800px) {
  .hero { padding: 48px 0 64px; }
  .product-grid { gap: 20px; }
  .product-content { padding: 22px; }
  .product-name { font-size: 22px; }
  .store-button { padding-inline: 10px; }
}
@media (max-width: 38rem) {
  :root { --page-gutter: 2rem; }
}
@media (max-width: 600px) {
  .hero { padding: 36px 0 52px; }
  .hero-label { font-size: 12px; }
  .hero-description { font-size: 15px; max-width: 360px; }
  .desktop-break { display: none; }
  .collection-toolbar { flex-direction: column; align-items: stretch; gap: 12px; margin-bottom: 20px; }
  .filters { justify-content: space-between; }
  .filter-button { flex: 1; padding: 10px 8px; font-size: 12px; }
  .filter-count { margin-left: 3px; }
  .result-count { text-align: right; font-size: 12px; }
  .product-grid { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .product-content { padding: 24px; }
  .category-label { top: 16px; left: 16px; }
  .sample-note { margin-bottom: 44px; }
  .site-footer { padding-top: var(--space-2xl); }
  .footer-bottom { margin-top: var(--space-2xl); flex-wrap: wrap; gap: var(--space-sm); }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
  .product-card:hover, .product-actions a:active { transform: none; }
}

/* 6. Ngôn ngữ: cùng cấu trúc và trạng thái với Portfolio. */
.languages { display: flex; align-items: center; flex-shrink: 0; gap: var(--language-switch-gap); padding: var(--language-switch-padding); border: 1px solid var(--color-rule); border-radius: var(--language-switch-radius); }
.languages button { min-width: 44px; min-height: 44px; padding: 0; border: 0; border-radius: var(--language-switch-item-radius); background: transparent; color: var(--color-header-muted); font-size: .75rem; font-weight: 600; cursor: pointer; }
.languages button[aria-pressed="true"] { border-radius: var(--language-switch-selected-radius); background: var(--color-surface); color: var(--color-header-ink); box-shadow: 0 1px 3px var(--color-language-shadow); }
.languages button:hover { color: var(--color-header-ink); }
.languages button:active:not(:disabled) { background: var(--color-rule); transform: none; }
.languages button:disabled { color: var(--color-muted); cursor: not-allowed; }
.languages button:focus-visible { outline-width: 2px; }
html:lang(ja) h1 { font-size: clamp(28px, 4.5vw, 56px); line-height: 1.45; letter-spacing: -.025em; }
html:lang(ja) .category-label { letter-spacing: 0; }
@media (max-width: 700px) {
  .site-header { flex-wrap: wrap; min-height: auto; padding-block: var(--space-lg) 0; gap: var(--space-sm) var(--space-md); justify-content: space-between; }
  .header-nav { order: 3; width: 100%; margin-left: 0; }
}
@media (max-width: 340px) {
  .site-header { column-gap: 0; }
}
@media (max-width: 600px) {
  .filter-button { padding-inline: 6px; }
  html:lang(ja) .filter-button { font-size: 11px; padding-inline: 4px; }
}