/* =============================================================================
   Vovinam Digital — landing · VVN-INFRA-04-LANDING-REDESIGN
   -----------------------------------------------------------------------------
   Design system sinh bởi skill ui-ux-pro-max (xem design-system/vovinam-digital/):
     · Pattern    App Store Style Landing (+ Feature-Rich Showcase cho lưới sản phẩm)
     · Style      Soft UI Evolution — bóng đổ mềm, tương phản rõ, WCAG AA+
     · Typography Barlow Condensed (display) + Barlow (body) — bộ "Sports/Fitness"
     · Colors     "Sports Team/Club" (đỏ #DC2626 + vàng vô địch) khoá theo nhận
                  diện Vovinam Digital: đỏ logo, navy #0B2E6B, vàng #FFC107
     · Dials      variance 7 · motion 6 · density 4
   Không dùng Tailwind/Font Awesome CDN nữa: toàn bộ token + component nằm ở đây,
   icon là SVG sprite trong index.html.
   ============================================================================= */

/* Font nạp bằng <link> trong index.html để tải song song với file này. */

/* =============================================================================
   1. TOKENS
   ========================================================================== */

:root {
    /* --- Primitive: nhận diện Vovinam ------------------------------------- */
    --red-400: #f05252;
    --red-500: #dc2626;
    --red-600: #b91c1c;
    --red-700: #911616;

    --navy-950: #04101f;
    --navy-900: #071b3d;
    --navy-800: #0b2e6b;
    --navy-700: #123f8c;
    --navy-600: #1b52ad;

    --gold-300: #ffd45c;
    --gold-400: #ffc107;
    --gold-500: #e0a800;

    --ink-900: #0b1220;
    --ink-800: #1e293b;
    --ink-700: #334155;
    --ink-500: #64748b;
    --ink-400: #94a3b8;

    --paper: #ffffff;
    --paper-alt: #f4f7fc;
    --paper-line: #e2e8f0;

    /* --- Semantic ---------------------------------------------------------- */
    --color-primary: var(--red-500);
    --color-primary-hover: var(--red-600);
    --color-on-primary: #ffffff;
    --color-accent: var(--gold-400);
    --color-accent-hover: var(--gold-500);
    --color-on-accent: #14213d;

    --surface: var(--paper);
    --surface-alt: var(--paper-alt);
    --surface-invert: var(--navy-900);
    --surface-invert-alt: var(--navy-950);

    --text: var(--ink-900);
    --text-muted: var(--ink-700);
    --text-subtle: var(--ink-500);
    --text-invert: #ffffff;
    --text-invert-muted: #c3d0e6;

    --border: var(--paper-line);
    --border-invert: rgba(255, 255, 255, 0.14);
    --ring: var(--gold-400);

    /* --- Typography -------------------------------------------------------- */
    --font-display: 'Barlow Condensed', 'Arial Narrow', 'Segoe UI', system-ui, sans-serif;
    --font-body: 'Barlow', 'Segoe UI', system-ui, -apple-system, Roboto, 'Helvetica Neue', Arial, sans-serif;

    --text-hero: clamp(2.6rem, 7.4vw, 5.4rem);
    --text-h2: clamp(2rem, 4.4vw, 3.25rem);
    --text-h3: clamp(1.35rem, 2vw, 1.75rem);
    --text-lead: clamp(1.05rem, 1.3vw, 1.2rem);
    --text-body: 1.0625rem;
    --text-sm: 0.9375rem;
    --text-xs: 0.8125rem;

    /* --- Spacing (density 4/10 — standard) --------------------------------- */
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 24px;
    --space-6: 32px;
    --space-7: 48px;
    --space-8: 64px;
    --space-9: 96px;

    --section-y: clamp(64px, 8vw, 112px);
    --container: 1200px;
    --gutter: clamp(16px, 4vw, 40px);
    --header-h: 72px;

    /* --- Radius / shadow (Soft UI Evolution) ------------------------------- */
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 22px;
    --radius-xl: 32px;
    --radius-pill: 999px;

    --shadow-sm: 0 1px 2px rgba(11, 18, 32, 0.06), 0 2px 8px rgba(11, 18, 32, 0.05);
    --shadow-md: 0 4px 12px rgba(11, 18, 32, 0.07), 0 12px 28px rgba(11, 18, 32, 0.08);
    --shadow-lg: 0 12px 24px rgba(11, 18, 32, 0.1), 0 32px 64px rgba(11, 18, 32, 0.14);
    --shadow-red: 0 10px 30px rgba(220, 38, 38, 0.28);
    --shadow-gold: 0 10px 30px rgba(255, 193, 7, 0.28);

    /* --- Motion ------------------------------------------------------------ */
    --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
    --dur-fast: 160ms;
    --dur: 240ms;
    --dur-slow: 420ms;

    /* --- Z-index scale (không dùng số tuỳ tiện) ---------------------------- */
    --z-base: 1;
    --z-sticky: 20;
    --z-header: 30;
    --z-drawer: 40;
    --z-modal: 50;
}

/* =============================================================================
   2. BASE
   ========================================================================== */

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    -webkit-text-size-adjust: 100%;
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--surface);
    color: var(--text);
    font-family: var(--font-body);
    font-size: var(--text-body);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

body.is-locked {
    overflow: hidden;
}

h1,
h2,
h3,
h4 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.05;
    letter-spacing: -0.01em;
    margin: 0;
    text-wrap: balance;
}

p {
    margin: 0;
}

img {
    max-width: 100%;
    display: block;
}

a {
    color: inherit;
    text-decoration: none;
}

ul {
    margin: 0;
    padding: 0;
    list-style: none;
}

button {
    font: inherit;
    color: inherit;
}

:focus-visible {
    outline: 3px solid var(--ring);
    outline-offset: 3px;
    border-radius: var(--radius-sm);
}

::selection {
    background: var(--color-accent);
    color: var(--color-on-accent);
}

.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-link {
    position: absolute;
    left: 50%;
    top: -100px;
    transform: translateX(-50%);
    z-index: var(--z-modal);
    background: var(--color-accent);
    color: var(--color-on-accent);
    font-weight: 700;
    padding: 12px 20px;
    border-radius: 0 0 var(--radius-md) var(--radius-md);
    transition: top var(--dur) var(--ease-out);
}

.skip-link:focus {
    top: 0;
}

/* =============================================================================
   3. LAYOUT
   ========================================================================== */

.container {
    width: 100%;
    max-width: var(--container);
    margin-inline: auto;
    padding-inline: var(--gutter);
}

.section {
    position: relative;
    padding-block: var(--section-y);
    background: var(--surface);
}

.section--alt {
    background: var(--surface-alt);
}

.section--invert {
    background: var(--surface-invert);
    color: var(--text-invert);
}

.section--invert .section-title,
.section--invert h2,
.section--invert h3 {
    color: var(--text-invert);
}

.section--invert p {
    color: var(--text-invert-muted);
}

.section-head {
    max-width: 62ch;
    margin-bottom: var(--space-7);
}

.section-head--center {
    margin-inline: auto;
    text-align: center;
}

.section-title {
    font-size: var(--text-h2);
    text-transform: uppercase;
    margin-block: var(--space-3);
}

.section-lead {
    font-size: var(--text-lead);
    color: var(--text-muted);
    max-width: 60ch;
}

.section--invert .section-lead {
    color: var(--text-invert-muted);
}

.split {
    display: grid;
    grid-template-columns: 1fr;
    gap: clamp(32px, 5vw, 72px);
    align-items: center;
}

@media (min-width: 920px) {
    .split {
        grid-template-columns: 1fr 1fr;
    }

    .split--media-first > .split__media {
        order: -1;
    }
}

/* =============================================================================
   4. COMPONENTS
   ========================================================================== */

/* --- Eyebrow / badge ------------------------------------------------------ */

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    font-family: var(--font-display);
    font-size: var(--text-xs);
    font-weight: 600;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--color-primary);
}

.eyebrow::before {
    content: '';
    width: 28px;
    height: 3px;
    border-radius: 2px;
    background: currentColor;
}

.eyebrow--gold {
    color: var(--color-accent);
}

.eyebrow--plain::before {
    display: none;
}

.chip {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: 6px 14px;
    border-radius: var(--radius-pill);
    background: rgba(220, 38, 38, 0.08);
    color: var(--color-primary);
    border: 1px solid rgba(220, 38, 38, 0.18);
    font-size: var(--text-xs);
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

.chip--gold {
    background: rgba(255, 193, 7, 0.12);
    color: var(--gold-300);
    border-color: rgba(255, 193, 7, 0.32);
}

/* --- Icon ----------------------------------------------------------------- */

.icon {
    width: 24px;
    height: 24px;
    flex: none;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.75;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.icon--sm {
    width: 18px;
    height: 18px;
}

.icon--lg {
    width: 30px;
    height: 30px;
}

.icon--solid {
    fill: currentColor;
    stroke: none;
}

/* --- Button --------------------------------------------------------------- */

.btn {
    --btn-bg: var(--color-primary);
    --btn-fg: var(--color-on-primary);
    --btn-shadow: var(--shadow-red);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    min-height: 48px;
    padding: 12px 26px;
    border: 0;
    border-radius: var(--radius-sm);
    background: var(--btn-bg);
    color: var(--btn-fg);
    font-family: var(--font-display);
    font-size: 1.0625rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    cursor: pointer;
    box-shadow: var(--btn-shadow);
    transition: transform var(--dur) var(--ease-out), background-color var(--dur) var(--ease-out),
        box-shadow var(--dur) var(--ease-out), color var(--dur) var(--ease-out);
}

.btn:hover {
    background: var(--color-primary-hover);
    transform: translateY(-2px);
}

.btn:active {
    transform: translateY(0);
}

.btn--gold {
    --btn-bg: var(--color-accent);
    --btn-fg: var(--color-on-accent);
    --btn-shadow: var(--shadow-gold);
}

.btn--gold:hover {
    background: var(--color-accent-hover);
}

.btn--light {
    --btn-bg: #ffffff;
    --btn-fg: var(--navy-800);
    --btn-shadow: var(--shadow-md);
}

.btn--light:hover {
    background: #eef2fa;
}

.btn--ghost {
    --btn-bg: transparent;
    --btn-fg: currentColor;
    --btn-shadow: none;
    border: 2px solid currentColor;
}

.btn--ghost:hover {
    background: rgba(255, 255, 255, 0.12);
    border-color: currentColor;
}

.btn--sm {
    min-height: 44px;
    padding: 8px 18px;
    font-size: 0.9375rem;
}

.btn-row {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4);
    align-items: center;
}

/* Link kiểu "đọc tiếp" */
.link-arrow {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    min-height: 44px;
    background: none;
    border: 0;
    padding: 0;
    color: var(--color-primary);
    font-family: var(--font-display);
    font-size: 1.0625rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    cursor: pointer;
    transition: color var(--dur) var(--ease-out);
}

.link-arrow .icon {
    transition: transform var(--dur) var(--ease-out);
}

.link-arrow:hover {
    color: var(--color-primary-hover);
}

.link-arrow:hover .icon {
    transform: translateX(4px);
}

.link-arrow[aria-disabled='true'] {
    color: var(--text-subtle);
    cursor: default;
}

/* --- Card ----------------------------------------------------------------- */

.card {
    display: flex;
    flex-direction: column;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out),
        border-color var(--dur) var(--ease-out);
}

.card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: rgba(220, 38, 38, 0.28);
}

.card__media {
    position: relative;
    aspect-ratio: 16 / 10;
    overflow: hidden;
    background: var(--navy-900);
}

.card__media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 700ms var(--ease-out);
}

.card:hover .card__media img {
    transform: scale(1.06);
}

.card__badge {
    position: absolute;
    top: var(--space-3);
    right: var(--space-3);
    display: grid;
    place-items: center;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-sm);
    background: rgba(255, 255, 255, 0.94);
    color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

.card__body {
    display: flex;
    flex-direction: column;
    flex: 1;
    gap: var(--space-3);
    padding: var(--space-5);
}

.card__title {
    font-size: var(--text-h3);
    text-transform: uppercase;
}

.card__text {
    color: var(--text-muted);
    font-size: var(--text-sm);
    flex: 1;
}

/* 4 thẻ: 1 cột → 2 cột → 4 cột, không để hàng cuối lẻ một thẻ */
.card-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-5);
}

@media (min-width: 640px) {
    .card-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1080px) {
    .card-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* --- Feature (icon + text) ------------------------------------------------ */

.feature-list {
    display: grid;
    gap: var(--space-4);
    margin-block: var(--space-6);
}

.feature {
    display: flex;
    gap: var(--space-4);
    padding: var(--space-4);
    background: var(--surface-alt);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}

.feature:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}

.feature__icon {
    display: grid;
    place-items: center;
    width: 52px;
    height: 52px;
    flex: none;
    border-radius: var(--radius-sm);
    background: var(--surface);
    color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

.feature__body {
    display: block;
}

.feature__title {
    display: block;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.25rem;
    line-height: 1.2;
    text-transform: uppercase;
}

.feature__text {
    display: block;
    color: var(--text-muted);
    font-size: var(--text-sm);
    margin-top: 4px;
}

/* Danh sách tick trên nền tối */
.check-list {
    display: grid;
    gap: var(--space-3);
    margin-block: var(--space-6);
}

.check-list--2col {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.check-list li {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-size: 1.0625rem;
    color: var(--text-invert);
}

.check-list__mark {
    display: grid;
    place-items: center;
    width: 32px;
    height: 32px;
    flex: none;
    border-radius: var(--radius-pill);
    background: rgba(255, 193, 7, 0.16);
    color: var(--color-accent);
}

/* --- Frame ảnh ------------------------------------------------------------ */

.media-frame {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.media-frame img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 700ms var(--ease-out);
}

.media-frame:hover img {
    transform: scale(1.04);
}

.media-frame__tint {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(4, 16, 31, 0.72), rgba(4, 16, 31, 0.05) 55%);
    pointer-events: none;
}

.media-note {
    position: absolute;
    left: var(--space-4);
    bottom: var(--space-4);
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    background: rgba(4, 16, 31, 0.72);
    backdrop-filter: blur(6px);
    border: 1px solid rgba(255, 255, 255, 0.18);
    color: #fff;
    font-size: var(--text-xs);
    font-weight: 600;
    letter-spacing: 0.04em;
}

.media-note__dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #22c55e;
    box-shadow: 0 0 0 4px rgba(34, 197, 94, 0.22);
}

.media-note--top {
    top: var(--space-4);
    left: auto;
    right: var(--space-4);
    bottom: auto;
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.16em;
}

/* =============================================================================
   5. HEADER + NAV
   ========================================================================== */

.site-header {
    position: fixed;
    inset-inline: 0;
    top: 0;
    z-index: var(--z-header);
    background: linear-gradient(to bottom, rgba(4, 16, 31, 0.78), rgba(4, 16, 31, 0));
    transition: background-color var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}

.site-header.is-scrolled {
    background: rgba(4, 16, 31, 0.94);
    backdrop-filter: blur(12px);
    box-shadow: 0 1px 0 rgba(255, 255, 255, 0.08), var(--shadow-md);
}

.site-header__bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-5);
    height: var(--header-h);
}

.site-header__logo {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    padding-inline: 2px;
}

.site-header__logo img {
    height: 34px;
    width: auto;
}

.site-nav {
    display: none;
    align-items: center;
    gap: clamp(16px, 2.2vw, 34px);
}

.site-nav a {
    position: relative;
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    padding-block: 6px;
    color: rgba(255, 255, 255, 0.86);
    font-family: var(--font-display);
    font-size: 1.0625rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    transition: color var(--dur) var(--ease-out);
}

.site-nav a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 100%;
    height: 2px;
    background: var(--color-accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--dur) var(--ease-out);
}

.site-nav a:hover,
.site-nav a.is-current {
    color: #fff;
}

.site-nav a:hover::after,
.site-nav a.is-current::after {
    transform: scaleX(1);
}

.site-header__actions {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.site-header__cta {
    display: none;
}

.nav-toggle {
    display: inline-grid;
    place-items: center;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    border: 1px solid rgba(255, 255, 255, 0.28);
    background: rgba(255, 255, 255, 0.06);
    color: #fff;
    cursor: pointer;
    transition: background-color var(--dur) var(--ease-out);
}

.nav-toggle:hover {
    background: rgba(255, 255, 255, 0.16);
}

@media (min-width: 1024px) {
    .site-nav {
        display: flex;
    }

    .site-header__cta {
        display: inline-flex;
    }

    .nav-toggle {
        display: none;
    }
}

/* Drawer mobile */
.mobile-nav {
    position: fixed;
    inset: 0;
    z-index: var(--z-drawer);
    display: grid;
    grid-template-columns: 1fr;
    pointer-events: none;
}

.mobile-nav[hidden] {
    display: none;
}

.mobile-nav__scrim {
    position: absolute;
    inset: 0;
    background: rgba(4, 16, 31, 0.6);
    opacity: 0;
    transition: opacity var(--dur) var(--ease-out);
}

.mobile-nav__panel {
    position: relative;
    margin-left: auto;
    width: min(360px, 86vw);
    height: 100%;
    padding: calc(var(--header-h) + 16px) var(--space-5) var(--space-6);
    background: var(--navy-950);
    border-left: 1px solid var(--border-invert);
    transform: translateX(100%);
    transition: transform var(--dur-slow) var(--ease-out);
    overflow-y: auto;
}

.mobile-nav.is-open {
    pointer-events: auto;
}

.mobile-nav.is-open .mobile-nav__scrim {
    opacity: 1;
}

.mobile-nav.is-open .mobile-nav__panel {
    transform: translateX(0);
}

/* :not(.btn) — nếu không, quy tắc này thắng .btn--gold về độ ưu tiên và biến nút
   CTA thành chữ trắng trên nền vàng (tương phản 1.6:1). */
.mobile-nav a:not(.btn) {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 52px;
    padding-block: 10px;
    border-bottom: 1px solid var(--border-invert);
    color: rgba(255, 255, 255, 0.9);
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.mobile-nav a:not(.btn):hover {
    color: var(--color-accent);
}

.mobile-nav .btn {
    width: 100%;
    margin-top: var(--space-5);
}

/* =============================================================================
   6. HERO
   ========================================================================== */

.hero-collection {
    position: relative;
    background: var(--navy-950);
    isolation: isolate;
}

.hero-section {
    display: none;
    position: relative;
    min-height: min(92svh, 880px);
    padding-top: calc(var(--header-h) + clamp(32px, 6vw, 72px));
    padding-bottom: clamp(220px, 26vw, 300px);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: #fff;
}

.hero-section.is-active {
    display: block;
}

.js .hero-section.is-active {
    animation: hero-in var(--dur-slow) var(--ease-out) both;
}

@keyframes hero-in {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

/* Scrim: chữ trên ảnh nền phải đạt >= 4.5:1 nên phủ 2 lớp gradient. Lớp ngang lo
   phần chữ bên trái, lớp dọc lo dải thumbnail phía dưới. */
.hero-section::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(100deg, rgba(4, 16, 31, 0.92) 0%, rgba(4, 16, 31, 0.72) 42%, rgba(4, 16, 31, 0.2) 74%,
            rgba(4, 16, 31, 0.42) 100%);
}

.hero-section::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(4, 16, 31, 0.92) 4%, rgba(4, 16, 31, 0) 34%);
}

.hero-content {
    position: relative;
    z-index: var(--z-base);
    max-width: 640px;
}

.hero-kicker {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: 6px 16px;
    border-radius: var(--radius-pill);
    background: rgba(220, 38, 38, 0.92);
    color: #fff;
    font-family: var(--font-display);
    font-size: var(--text-xs);
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
}

.hero-heading-text {
    font-size: var(--text-hero);
    line-height: 0.94;
    letter-spacing: -0.015em;
    text-transform: uppercase;
    margin-block: var(--space-4) var(--space-4);
    text-shadow: 0 4px 30px rgba(0, 0, 0, 0.45);
}

.hero-sub-heading {
    font-family: var(--font-display);
    font-size: var(--text-xs);
    font-weight: 600;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin: 0 0 var(--space-2);
}

.hero-sub-heading-content {
    font-size: var(--text-lead);
    color: rgba(255, 255, 255, 0.9);
    max-width: 56ch;
    margin-bottom: var(--space-6);
}

.hero-social {
    position: absolute;
    left: max(12px, calc((100vw - var(--container)) / 2 - 56px));
    top: 50%;
    transform: translateY(-50%);
    z-index: var(--z-sticky);
    display: none;
    flex-direction: column;
    align-items: center;
    gap: var(--space-4);
}

.hero-social__line {
    width: 1px;
    height: 64px;
    background: linear-gradient(to bottom, transparent, rgba(255, 255, 255, 0.5), transparent);
}

.hero-social a {
    display: grid;
    place-items: center;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-pill);
    border: 1px solid rgba(255, 255, 255, 0.24);
    color: #fff;
    transition: background-color var(--dur) var(--ease-out), color var(--dur) var(--ease-out),
        border-color var(--dur) var(--ease-out);
}

.hero-social a:hover {
    background: var(--color-accent);
    border-color: var(--color-accent);
    color: var(--color-on-accent);
}

@media (min-width: 1180px) {
    .hero-social {
        display: flex;
    }
}

/* --- Rail chọn slide ------------------------------------------------------- */

.hero-rail {
    position: absolute;
    left: 0;
    right: 0;
    bottom: clamp(24px, 4vw, 48px);
    z-index: var(--z-sticky);
}

.hero-rail__inner {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    gap: var(--space-4);
}

.hero-thumbnail-list {
    display: flex;
    gap: var(--space-3);
    overflow-x: auto;
    padding-bottom: var(--space-2);
    scroll-snap-type: x mandatory;
    scrollbar-width: none;
}

.hero-thumbnail-list::-webkit-scrollbar {
    display: none;
}

.hero-thumbnail-item {
    position: relative;
    display: flex;
    flex-direction: column;
    flex: none;
    width: clamp(132px, 15vw, 176px);
    padding: 0;
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-md);
    background: rgba(4, 16, 31, 0.55);
    color: #fff;
    text-align: left;
    overflow: hidden;
    cursor: pointer;
    scroll-snap-align: start;
    transition: transform var(--dur) var(--ease-out), border-color var(--dur) var(--ease-out),
        box-shadow var(--dur) var(--ease-out);
}

.hero-thumbnail-item img {
    width: 100%;
    height: clamp(76px, 8vw, 96px);
    object-fit: cover;
    opacity: 0.7;
    transition: opacity var(--dur) var(--ease-out), transform 700ms var(--ease-out);
}

.hero-thumbnail-item:hover {
    transform: translateY(-4px);
    border-color: rgba(255, 255, 255, 0.5);
}

.hero-thumbnail-item:hover img {
    opacity: 0.92;
    transform: scale(1.05);
}

.hero-thumbnail-item.active {
    border-color: var(--color-accent);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.45);
}

.hero-thumbnail-item.active img {
    opacity: 1;
}

.thumb-content {
    display: flex;
    flex: 1;
    align-items: center;
    padding: 10px 12px 16px;
}

.thumb-title {
    font-family: var(--font-display);
    font-size: 0.9375rem;
    font-weight: 600;
    line-height: 1.15;
    letter-spacing: 0.03em;
    text-transform: uppercase;
}

/* Thanh tiến trình autoplay của thumbnail đang chọn */
.hero-thumbnail-item::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    height: 3px;
    width: 100%;
    background: var(--color-accent);
    transform: scaleX(0);
    transform-origin: left;
}

.hero-thumbnail-item.active::after {
    transform: scaleX(1);
    transition: transform 120ms linear;
}

.js .hero-thumbnail-item.active.is-timing::after {
    animation: thumb-progress var(--hero-delay, 7s) linear forwards;
}

@keyframes thumb-progress {
    from {
        transform: scaleX(0);
    }

    to {
        transform: scaleX(1);
    }
}

.hero-controls {
    display: none;
    align-items: center;
    gap: var(--space-2);
    padding-bottom: var(--space-2);
}

.hero-controls button {
    display: grid;
    place-items: center;
    width: 46px;
    height: 46px;
    border-radius: var(--radius-pill);
    border: 1px solid rgba(255, 255, 255, 0.28);
    background: rgba(4, 16, 31, 0.55);
    color: #fff;
    cursor: pointer;
    transition: background-color var(--dur) var(--ease-out), transform var(--dur) var(--ease-out);
}

.hero-controls button:hover {
    background: var(--color-primary);
    border-color: var(--color-primary);
}

@media (min-width: 1024px) {
    .hero-controls {
        display: flex;
    }
}

/* =============================================================================
   7. SECTION: HỆ SINH THÁI (lưới sản phẩm)
   ========================================================================== */

.solutions-grid .card:nth-child(1) {
    --reveal-delay: 0ms;
}

.solutions-grid .card:nth-child(2) {
    --reveal-delay: 80ms;
}

.solutions-grid .card:nth-child(3) {
    --reveal-delay: 160ms;
}

.solutions-grid .card:nth-child(4) {
    --reveal-delay: 240ms;
}

/* =============================================================================
   8. SECTION: BAMBOY (panel công nghệ)
   ========================================================================== */

.tech-panel {
    position: relative;
    display: grid;
    place-items: center;
    aspect-ratio: 4 / 5;
    max-height: 560px;
    border-radius: var(--radius-xl);
    border: 1px solid var(--border-invert);
    background: linear-gradient(150deg, #0a1f47 0%, #16113d 100%);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.tech-panel__texture {
    position: absolute;
    inset: 0;
    background-image: url('./assets/img/texture-circuit-board.svg');
    opacity: 0.18;
}

.tech-panel__glow {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 62%;
    aspect-ratio: 1;
    transform: translate(-50%, -50%);
    border-radius: 50%;
    background: rgba(255, 193, 7, 0.3);
    filter: blur(80px);
    transition: background-color var(--dur-slow) var(--ease-out);
}

.tech-panel:hover .tech-panel__glow {
    background: rgba(255, 193, 7, 0.42);
}

.tech-panel img {
    position: relative;
    z-index: var(--z-base);
    width: 74%;
    height: 74%;
    object-fit: contain;
    filter: drop-shadow(0 0 22px rgba(255, 193, 7, 0.4));
}

/* =============================================================================
   9. SECTION: VOVINAM ID
   ========================================================================== */

.section--id {
    background: radial-gradient(120% 120% at 12% 0%, var(--navy-700) 0%, var(--navy-900) 46%, var(--navy-950) 100%);
    color: var(--text-invert);
    overflow: hidden;
}

.section--id .section-title,
.section--id h2 {
    color: var(--text-invert);
}

.section--id .section-lead,
.section--id p {
    color: var(--text-invert-muted);
}

.section--id__pattern {
    position: absolute;
    inset: 0;
    background-image: url('./assets/img/texture-cubes.png');
    opacity: 0.12;
    pointer-events: none;
}

.id-card-stack {
    position: relative;
    display: grid;
    place-items: center;
    min-height: 520px;
}

.id-card {
    position: relative;
    z-index: var(--z-base);
    width: min(320px, 78vw);
    aspect-ratio: 320 / 500;
    border-radius: var(--radius-xl);
    border: 4px solid rgba(255, 255, 255, 0.12);
    background: #0f2069;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    transform: rotate(2deg);
    transition: transform var(--dur-slow) var(--ease-out);
}

.id-card:hover {
    transform: rotate(0deg) translateY(-6px);
}

.id-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.id-card-stack::before {
    content: '';
    position: absolute;
    width: min(320px, 78vw);
    aspect-ratio: 320 / 500;
    border-radius: var(--radius-xl);
    border: 4px solid rgba(255, 255, 255, 0.06);
    background: linear-gradient(to bottom, #1e293b, #0f172a);
    transform: rotate(-7deg) translate(18px, 12px);
    opacity: 0.6;
}

/* =============================================================================
   10. SECTION: TẢI ỨNG DỤNG
   ========================================================================== */

.download-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: clamp(32px, 5vw, 64px);
    align-items: center;
}

@media (min-width: 920px) {
    .download-grid {
        grid-template-columns: 1.05fr 0.95fr;
    }
}

.qr-row {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-5);
    margin-top: var(--space-5);
}

.qr-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    background: var(--surface);
    box-shadow: var(--shadow-sm);
    transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}

.qr-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.qr-card img {
    width: 138px;
    height: 138px;
    object-fit: contain;
    border-radius: var(--radius-sm);
    background: #144984;
}

.qr-card span {
    font-family: var(--font-display);
    font-size: 1rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-muted);
}

/* Ảnh nguồn là bản chụp ngang 1440x681, nên đóng khung ngang thay vì giả lập
   khung điện thoại dọc. */
.phone-mock {
    position: relative;
    display: grid;
    place-items: center;
}

.phone-mock__glow {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 88%;
    aspect-ratio: 1;
    transform: translate(-50%, -50%);
    border-radius: 50%;
    background: rgba(220, 38, 38, 0.16);
    filter: blur(90px);
}

.phone-mock img {
    position: relative;
    z-index: var(--z-base);
    width: 100%;
    aspect-ratio: 16 / 11;
    object-fit: cover;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
}

/* =============================================================================
   11. FOOTER
   ========================================================================== */

.vvd-footer {
    background: var(--navy-950);
    color: var(--text-invert-muted);
    padding-block: var(--space-8) var(--space-6);
    border-top: 3px solid var(--color-primary);
}

/* auto-fit đẩy cột "đăng ký nhận tin" xuống hàng hai và chừa mảng trống, nên
   khai báo cột tường minh: thương hiệu — 3 cột liên kết — form. */
.vvd-footer__grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-6) var(--space-5);
}

.footer-col {
    min-width: 0;
}

@media (min-width: 620px) {
    .vvd-footer__grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-col.col-5 {
        grid-column: span 2;
    }
}

@media (min-width: 1100px) {
    .vvd-footer__grid {
        grid-template-columns: 1.6fr 0.9fr 0.9fr 0.9fr 1.5fr;
    }

    .footer-col.col-5 {
        grid-column: auto;
    }
}

.vvd-negative-space-logo {
    height: 38px;
    width: auto;
    margin-bottom: var(--space-4);
}

.section-subheading {
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: #fff;
    margin: 0 0 var(--space-4);
}

.contact-info-container {
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    margin-bottom: var(--space-3);
    font-size: var(--text-sm);
    line-height: 1.55;
}

.contact-info-container .icon {
    color: var(--color-accent);
    margin-top: 3px;
}

.contact-info-container a:hover {
    color: var(--color-accent);
}

.text-bold-700 {
    font-weight: 700;
    color: #fff;
}

.links-container {
    display: grid;
    gap: var(--space-1);
}

.link-item a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    font-size: var(--text-sm);
    transition: color var(--dur) var(--ease-out);
}

.link-item a:hover {
    color: var(--color-accent);
}

.link-item.is-pending {
    opacity: 0.6;
    cursor: not-allowed;
    font-size: var(--text-sm);
}

.link-item.is-pending small {
    display: block;
    font-size: var(--text-xs);
    color: var(--ink-400);
}

.email-subscription {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
    margin-top: var(--space-3);
}

.email-input {
    flex: 1 1 11rem;
    min-width: 0;
    padding: 12px 14px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-invert);
    background: rgba(255, 255, 255, 0.06);
    color: #fff;
    font: inherit;
    font-size: var(--text-sm);
}

.email-input::placeholder {
    color: var(--ink-400);
}

.email-input:focus {
    border-color: var(--color-accent);
    background: rgba(255, 255, 255, 0.1);
}

.email-subscription-btn {
    flex: none;
    min-height: 46px;
    padding: 10px 22px;
    border: 0;
    border-radius: var(--radius-sm);
    background: var(--color-primary);
    color: #fff;
    font-family: var(--font-display);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    cursor: pointer;
    transition: background-color var(--dur) var(--ease-out), transform var(--dur) var(--ease-out);
}

.email-subscription-btn:hover {
    background: var(--color-primary-hover);
    transform: translateY(-2px);
}

@media (max-width: 680px) {
    .email-input,
    .email-subscription-btn {
        flex: 1 1 100%;
    }
}

.footer-note {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: var(--space-3);
    margin-top: var(--space-7);
    padding-top: var(--space-5);
    border-top: 1px solid var(--border-invert);
    font-size: var(--text-xs);
}

.footer-social {
    display: flex;
    gap: var(--space-2);
}

.footer-social a {
    display: grid;
    place-items: center;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-pill);
    border: 1px solid var(--border-invert);
    transition: background-color var(--dur) var(--ease-out), color var(--dur) var(--ease-out);
}

.footer-social a:hover {
    background: var(--color-accent);
    color: var(--color-on-accent);
}

/* =============================================================================
   12. MODAL
   ========================================================================== */

.hero-modal {
    position: fixed;
    inset: 0;
    z-index: var(--z-modal);
    display: none;
    align-items: center;
    justify-content: center;
    padding: var(--space-4);
}

.hero-modal.is-open {
    display: flex;
}

.hero-modal__backdrop {
    position: absolute;
    inset: 0;
    /* scrim 55% — đủ tách nội dung nền theo checklist a11y */
    background: rgba(4, 16, 31, 0.72);
    backdrop-filter: blur(4px);
}

.hero-modal__dialog {
    position: relative;
    display: grid;
    grid-template-columns: 1fr;
    width: min(1000px, 100%);
    max-height: min(88svh, 780px);
    background: var(--surface);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    animation: modal-in var(--dur-slow) var(--ease-out) both;
}

@keyframes modal-in {
    from {
        opacity: 0;
        transform: translateY(18px) scale(0.98);
    }

    to {
        opacity: 1;
        transform: none;
    }
}

@media (min-width: 860px) {
    .hero-modal__dialog {
        grid-template-columns: 0.85fr 1.15fr;
    }
}

.hero-modal__media {
    position: relative;
    min-height: 200px;
    background: var(--navy-900);
}

.hero-modal__media img {
    width: 100%;
    height: 100%;
    max-height: 240px;
    object-fit: cover;
}

@media (min-width: 860px) {
    .hero-modal__media img {
        max-height: none;
    }
}

.hero-modal__content {
    padding: clamp(20px, 3vw, 40px);
    overflow-y: auto;
}

.hero-modal__kicker {
    font-family: var(--font-display);
    font-size: var(--text-xs);
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-primary);
}

.hero-modal__title {
    font-size: clamp(1.75rem, 3.4vw, 2.6rem);
    text-transform: uppercase;
    margin-block: var(--space-2) var(--space-4);
}

.hero-modal__desc {
    color: var(--text-muted);
}

.hero-modal__desc p {
    margin-bottom: var(--space-3);
}

.hero-modal__desc ul {
    list-style: disc;
    padding-left: 1.2rem;
    margin-bottom: var(--space-3);
}

.hero-modal__desc li {
    margin-bottom: 6px;
}

.hero-modal__close {
    position: absolute;
    top: 12px;
    right: 12px;
    z-index: var(--z-sticky);
    display: grid;
    place-items: center;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-pill);
    border: 1px solid rgba(255, 255, 255, 0.24);
    background: rgba(4, 16, 31, 0.66);
    color: #fff;
    cursor: pointer;
    transition: background-color var(--dur) var(--ease-out);
}

.hero-modal__close:hover {
    background: var(--color-primary);
}

.app-qr-container {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4);
    margin-top: var(--space-3);
}

.app-qr {
    text-align: center;
    font-size: var(--text-sm);
}

.app-qr img {
    width: 150px;
    height: 150px;
    border-radius: var(--radius-sm);
    background: #144984;
    padding: 8px;
    margin-bottom: 6px;
}

/* =============================================================================
   13. MOTION (reveal — tier "Standard" 300-450ms, stagger 60-80ms)
   ========================================================================== */

.js .reveal {
    opacity: 0;
    transform: translateY(24px);
}

.js .reveal.active {
    opacity: 1;
    transform: none;
    transition: opacity var(--dur-slow) var(--ease-out) var(--reveal-delay, 0ms),
        transform var(--dur-slow) var(--ease-out) var(--reveal-delay, 0ms);
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
    }

    .js .reveal {
        opacity: 1;
        transform: none;
    }
}

/* =============================================================================
   14. RESPONSIVE TINH CHỈNH
   ========================================================================== */

@media (max-width: 767px) {
    :root {
        --header-h: 64px;
    }

    .hero-section {
        min-height: min(96svh, 760px);
        padding-bottom: clamp(200px, 46vw, 260px);
        background-position: 62% center;
    }

    .hero-section::before {
        background: linear-gradient(180deg, rgba(4, 16, 31, 0.9) 0%, rgba(4, 16, 31, 0.72) 45%,
                rgba(4, 16, 31, 0.86) 100%);
    }

    .hero-heading-text {
        font-size: clamp(2.4rem, 12vw, 3.4rem);
    }

    .hero-sub-heading-content {
        font-size: 1rem;
    }

    .hero-thumbnail-item {
        width: 140px;
    }

    .id-card-stack {
        min-height: 440px;
    }

    .id-card-stack::before {
        display: none;
    }
}

@media (min-width: 768px) {
    .feature-list {
        gap: var(--space-3);
    }
}