/* fayol.vn - trang tĩnh, không JavaScript, không font hay script bên ngoài. Sáng / tối theo hệ điều hành. */

:root {
    color-scheme: light dark;
    --bg: #f6f8fc;
    --surface: #ffffff;
    --surface-2: #eef2f9;
    --text: #0b1f4b;
    --text-2: #4a5878;
    --border: #dde3ee;
    --primary: #1b3a8a;
    --primary-hover: #0b1f4b;
    --cta: #f59e0b;
    --cta-hover: #e08e00;
    --cta-text: #0b1f4b;
    --marker: #0f766e;
    --focus: #2563eb;
    --chip-soon-bg: #e3ecff;
    --chip-soon-text: #1e3fae;
    --chip-beta-bg: #fff1d6;
    --chip-beta-text: #8a4600;
    --glow: rgba(27, 58, 138, 0.09);
    --shadow: 0 1px 2px rgba(11, 31, 75, 0.04), 0 12px 32px -18px rgba(11, 31, 75, 0.22);
}

/* Nền tối = đúng màu nền của logo bản tối (#0a1020), để logo liền với trang. */
@media (prefers-color-scheme: dark) {
    :root {
        --bg: #0a1020;
        --surface: #111a2e;
        --surface-2: #16213a;
        --text: #e8edf7;
        --text-2: #a9b4cc;
        --border: #26324d;
        --primary: #9dbbff;
        --primary-hover: #c5d6ff;
        --cta: #f59e0b;
        --cta-hover: #fbb13c;
        --cta-text: #0b1f4b;
        --marker: #2dd4bf;
        --focus: #9dbbff;
        --chip-soon-bg: #1b2c55;
        --chip-soon-text: #bcd0ff;
        --chip-beta-bg: #3b2a0a;
        --chip-beta-text: #fcd38d;
        --glow: rgba(45, 212, 191, 0.07);
        --shadow: none;
    }
}

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

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

@media (prefers-reduced-motion: no-preference) {
    html { scroll-behavior: smooth; }
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif;
    font-size: 16px;
    line-height: 1.6;
    overflow-wrap: break-word;
}

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

a {
    color: var(--primary);
    text-decoration-thickness: 1px;
    text-underline-offset: 3px;
}
a:hover { color: var(--primary-hover); }
a:focus-visible {
    outline: 3px solid var(--focus);
    outline-offset: 3px;
    border-radius: 6px;
}

h1, h2, h3 { color: var(--text); }

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    padding: 0;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.skip {
    position: absolute;
    left: 16px;
    top: -100px;
    z-index: 10;
    padding: 10px 16px;
    border-radius: 10px;
    background: var(--surface);
    color: var(--primary);
    font-weight: 600;
    box-shadow: var(--shadow);
}
.skip:focus { top: 12px; }

.wrap {
    width: 100%;
    max-width: 1040px;
    margin: 0 auto;
    padding-inline: 16px;
}

/* Thanh trên */
.site-header .wrap {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding-block: 16px;
}
/* Logo ngang có lề trong bằng 1/8 chiều cao: kéo sang trái đúng phần đó để biểu tượng thẳng mép nội dung. */
.brand { display: inline-flex; flex: none; --logo-h: 48px; }
.brand img { height: var(--logo-h); width: auto; margin-left: calc(var(--logo-h) * -0.125); }
.nav {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: flex-end;
    gap: 4px 20px;
    font-size: 15px;
    font-weight: 500;
}
.nav a {
    color: var(--text-2);
    text-decoration: none;
    padding: 6px 0;
}
.nav a:hover { color: var(--text); }
.nav .nav-login {
    color: var(--primary);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 6px 14px;
    background: var(--surface);
}
.nav .nav-login:hover { color: var(--primary-hover); border-color: var(--primary); }

/* Phần đầu */
/* Lớp trên cùng phủ màu nền ở mép trên: vầng sáng không tạo vạch ngang dưới thanh trên (và không lộ khung nền của logo tối). */
.hero {
    background:
        linear-gradient(to bottom, var(--bg), transparent 40%),
        radial-gradient(70% 85% at 50% 35%, var(--glow), transparent 72%);
    text-align: center;
    padding: 56px 0 48px;
}
.hero h1 {
    font-size: clamp(30px, 4.2vw + 12px, 48px);
    line-height: 1.22;
    letter-spacing: -0.02em;
    max-width: 17em;
    margin: 0 auto 18px;
    text-wrap: balance;
}
.lead {
    font-size: clamp(17px, 0.5vw + 15px, 19px);
    color: var(--text-2);
    max-width: 38em;
    margin: 0 auto 28px;
    text-wrap: pretty;
}
.actions {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 22px;
    border: 1px solid transparent;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    line-height: 1.3;
    text-decoration: none;
}
.btn:focus-visible { border-radius: 12px; }
.btn-primary { background: var(--cta); border-color: var(--cta); color: var(--cta-text); }
.btn-primary:hover { background: var(--cta-hover); border-color: var(--cta-hover); color: var(--cta-text); }
.btn-secondary { background: var(--surface); border-color: var(--primary); color: var(--primary); }
.btn-secondary:hover { background: var(--surface-2); color: var(--primary-hover); }
.note {
    font-size: 14.5px;
    color: var(--text-2);
    margin: 16px auto 0;
}

/* Các phần */
.section { padding: 16px 0 40px; }
.section h2 {
    font-size: clamp(24px, 1.2vw + 19px, 30px);
    line-height: 1.25;
    letter-spacing: -0.01em;
    margin: 0 0 20px;
}

.products {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
}
.product {
    display: flex;
    flex-direction: column;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 24px;
    box-shadow: var(--shadow);
}
.product-head {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-bottom: 16px;
}
.product-head img { width: 52px; height: 52px; flex: none; }
.product-title {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 4px 10px;
}
.product h3 {
    font-size: 21px;
    line-height: 1.3;
    margin: 0;
}
.chip {
    display: inline-flex;
    align-items: center;
    padding: 2px 10px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 600;
    line-height: 1.6;
    white-space: nowrap;
}
.chip-soon { background: var(--chip-soon-bg); color: var(--chip-soon-text); }
.chip-beta { background: var(--chip-beta-bg); color: var(--chip-beta-text); }
.product-lead { font-weight: 600; margin: 0 0 10px; }
.product ul {
    color: var(--text-2);
    margin: 0 0 20px;
    padding-left: 1.2em;
}
.product li { margin-bottom: 6px; }
.product li::marker { color: var(--marker); }
.product-foot {
    margin: auto 0 0;
    padding-top: 14px;
    border-top: 1px solid var(--border);
    color: var(--text-2);
    font-size: 15px;
}

.split {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
}
.panel {
    background: var(--surface-2);
    border-radius: 20px;
    padding: 24px;
}
.panel h2 {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 22px;
    margin: 0 0 12px;
}
.ic {
    display: grid;
    place-items: center;
    flex: none;
    width: 38px;
    height: 38px;
    border-radius: 11px;
    background: var(--surface);
    color: var(--primary);
}
.ic svg { width: 20px; height: 20px; fill: currentColor; }
.panel p { color: var(--text-2); margin: 0 0 10px; }
.panel p:last-child { margin-bottom: 0; }
.facts {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 6px 16px;
    margin: 14px 0 0;
}
.facts dt { color: var(--text-2); }
.facts dd { margin: 0; font-weight: 600; }

.panel-en {
    background: var(--surface);
    border: 1px solid var(--border);
}
.panel-en ul {
    color: var(--text-2);
    margin: 0 0 10px;
    padding-left: 1.2em;
}
.panel-en li { margin-bottom: 6px; }
.panel-en li::marker { color: var(--marker); }
.panel-en strong { color: var(--text); }

/* Chân trang */
.site-footer {
    border-top: 1px solid var(--border);
    margin-top: 16px;
    padding: 24px 0 40px;
    color: var(--text-2);
    font-size: 14px;
}
.site-footer .wrap {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 8px 24px;
}
.site-footer p { margin: 0; }
.site-footer a { color: var(--text-2); }
.site-footer a:hover { color: var(--text); }
.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 4px 20px;
}

/* Trang 404 */
.notfound {
    max-width: 560px;
    margin: 0 auto;
    padding: 56px 16px;
    text-align: center;
}
.notfound .brand { margin-bottom: 32px; }
.notfound .brand img { margin-left: 0; }
.notfound h1 {
    font-size: 30px;
    line-height: 1.25;
    margin: 0 0 12px;
    text-wrap: balance;
}
.notfound p { color: var(--text-2); margin: 0 0 20px; }

@media (max-width: 760px) {
    .products,
    .split { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
    .site-header .wrap { padding-block: 12px; gap: 12px; }
    .brand { --logo-h: 38px; }
    .nav { gap: 4px 14px; }
    .nav .nav-wide { display: none; }
    .hero { padding: 32px 0 36px; }
    .actions {
        flex-direction: column;
        align-items: stretch;
        max-width: 360px;
        margin: 0 auto;
    }
    .product,
    .panel { padding: 20px; }
}

@media (max-width: 400px) {
    .facts { grid-template-columns: 1fr; gap: 0; }
    .facts dd { margin-bottom: 8px; }
}