/* ================= THIET LAP CHUNG ================= */

*,
*::before,
*::after {
    box-sizing: border-box;
}
:root {
    --sticky-offset: 88px;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--sticky-offset);
}

body {
    margin: 0;
    background-color: #f4f0e7;
    color: #292524;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 16px;
    line-height: 1.6;
}

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

/* ================= TYPOGRAPHY ================= */

h1,
h2,
h3 {
    margin-top: 0;
    color: #1c1917;
    font-family: Georgia, "Times New Roman", serif;
    font-weight: 700;
    line-height: 1.2;
}

h1 {
    margin-bottom: 24px;
    font-size: clamp(40px, 5vw, 64px);
    letter-spacing: -0.035em;
}

h2 {
    margin-bottom: 24px;
    font-size: clamp(28px, 3vw, 40px);
    letter-spacing: -0.02em;
}

h3 {
    margin-bottom: 8px;
    font-size: 19px;
}

p {
    margin: 0 0 16px;
    line-height: 1.75;
}

a {
    color: #70432f;
    text-underline-offset: 3px;
}

a:hover {
    color: #3f261a;
}

strong {
    color: #1c1917;
    font-weight: 700;
}

figcaption {
    margin-top: 8px;
    color: #78716c;
    font-size: 14px;
    line-height: 1.5;
}

article > p:last-child,
.value-card p:last-child,
.member p:last-child,
.sidebar > p:last-child {
    margin-bottom: 0;
}

/* ================= HEADER ================= */

.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;

    display: flex;
    align-items: center;
    gap: 16px;

    padding: 14px 24px;
    border-bottom: 1px solid #d6d3d1;

    background-color: rgba(244, 240, 231, 0.96);
    box-shadow: 0 4px 18px rgba(41, 37, 36, 0.08);
    backdrop-filter: blur(8px);
}

.site-name {
    flex-shrink: 0;
    color: #1c1917;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 30px;
    font-weight: 700;
    letter-spacing: -0.025em;
    text-decoration: none;
}

.tagline {
    flex-shrink: 0;
    margin: 0;
    color: #57534e;
    font-size: 12px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}
.tagline::before,
.tagline::after {
    content: "—";
    margin: 0 6px;
}

.main-nav {
    position: relative;
    margin-left: auto;
}

.main-nav ul {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;

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

.main-nav a {
    color: #44403c;
    font-size: 14px;
    font-weight: 500;
    text-decoration: none;
}

.main-nav a:hover {
    color: #70432f;
    text-decoration: underline;
    text-underline-offset: 4px;
}

.menu-toggle {
    display: none;
    width: 44px;
    height: 44px;
    padding: 10px;

    border: 1px solid #a8a29e;
    border-radius: 4px;
    background-color: transparent;
    cursor: pointer;
}

.menu-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    margin: 5px auto;
    background-color: #292524;
    transition: transform 200ms ease, opacity 200ms ease;
}

/* Man hinh trung binh: an tagline de danh cho cho nav */
@media (max-width: 900px) {
    .tagline {
        display: none;
    }
}

/* Mobile: thay danh sach nav bang nut hamburger */
@media (max-width: 640px) {
    .site-header {
        padding: 10px 16px;
    }

    .site-name {
        font-size: 26px;
    }

    .menu-toggle {
        display: block;
    }

    .main-nav ul {
        position: absolute;
        top: calc(100% + 10px);
        right: 0;

        display: none;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        min-width: 200px;
        padding: 8px;

        border: 1px solid #d6d3d1;
        border-radius: 4px;
        background-color: #f4f0e7;
        box-shadow: 0 10px 24px rgba(41, 37, 36, 0.16);
        text-align: left;
    }

    .main-nav.is-open ul {
        display: flex;
    }

    .main-nav a {
        display: block;
        padding: 10px 12px;
    }

    .main-nav.is-open .menu-toggle span:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }

    .main-nav.is-open .menu-toggle span:nth-child(2) {
        opacity: 0;
    }

    .main-nav.is-open .menu-toggle span:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }
}
/* ================= LAYOUT CHINH ================= */

.layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 32px 16px;
}

/*
 * Cac phan tu con cua main tham gia truc tiep
 * vao Grid cua .layout.
 */
main {
    display: contents;
}

#gioi-thieu,
#gia-tri,
#doi-ngu,
#lien-he,
.sidebar {
    min-width: 0;
}

#gioi-thieu {
    position: relative;
    isolation: isolate;
    overflow: hidden;

    display: flex;
    flex-direction: column;
    justify-content: flex-end;

    min-height: calc(100svh - 97px);
    padding: clamp(32px, 6vw, 80px);

    border-bottom: 0;
    color: #ffffff;
}

#gioi-thieu figure {
    position: absolute;
    inset: 0;
    z-index: -2;

    margin: 0;
}
#gioi-thieu figure img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}
#gioi-thieu figure::after {
    content: "";
    position: absolute;
    inset: 0;

    background:
        linear-gradient(
            to top,
            rgba(28, 25, 23, 0.88) 0%,
            rgba(28, 25, 23, 0.45) 55%,
            rgba(28, 25, 23, 0.15) 100%
        );
}
#gioi-thieu h1,
#gioi-thieu > p {
    position: relative;
    z-index: 1;
    max-width: 720px;
}
#gioi-thieu h1,
#gioi-thieu strong {
    color: #ffffff;
}
#gioi-thieu > p {
    font-size: clamp(16px, 2vw, 20px);
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.45);
}
#gioi-thieu figcaption {
    position: absolute;
    right: 16px;
    top: 16px;
    z-index: 2;

    margin: 0;
    color: rgba(255, 255, 255, 0.75);
    font-size: 12px;
}

#gia-tri,
#doi-ngu,
#lien-he {
    padding-bottom: 32px;
    border-bottom: 1px solid #d6d3d1;
}

.sidebar {
    border-left: 0 solid #d6d3d1;
}

/* ================= VALUE & TEAM GRID ================= */

.value-list,
.team-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;

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

.value-card,
.member {
    min-width: 0;
    padding: 24px;
    border: 1px solid #d6d3d1;
    background-color: #fafaf9;
}

.member img {
    width: 100%;
    aspect-ratio: 1 / 1;
    object-fit: cover;
}

@media (min-width: 600px) {
    .value-list,
    .team-list {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (min-width: 900px) {
    .value-list,
    .team-list {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

/* ================= DESKTOP LAYOUT ================= */

@media (min-width: 1024px) {
    .layout {
        grid-template-columns: minmax(0, 1fr) 280px;
        align-items: start;
    }

    #gioi-thieu {
        grid-column: 1 / -1;
        grid-row: 1;
    }

    #gia-tri {
        grid-column: 1;
        grid-row: 2;
    }

    #doi-ngu {
        grid-column: 1;
        grid-row: 3;
    }

    #lien-he {
        grid-column: 1;
        grid-row: 4;
    }

    .sidebar {
        grid-column: 2;
        grid-row: 2 / 5;
        align-self: start;

        padding-left: 24px;
        border-left-width: 1px;

        position: sticky;
        top: 88px;
    }
}

/* ================= CONTACT FORM ================= */

.contact-form {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
}

.contact-form p {
    margin: 0;
}

.contact-form label {
    display: inline-block;
    margin-bottom: 6px;
    font-weight: 600;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 12px 14px;

    border: 1px solid #a8a29e;
    border-radius: 4px;

    background-color: #ffffff;
    color: #292524;
    font: inherit;
}

.contact-form textarea {
    min-height: 130px;
    resize: vertical;
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: #57534e;
    outline: 2px solid #d6d3d1;
    outline-offset: 2px;
}

.contact-form button {
    padding: 12px 24px;

    border: 1px solid #292524;
    border-radius: 4px;

    background-color: #292524;
    color: #ffffff;
    font: inherit;
    font-weight: 600;

    cursor: pointer;
}

.contact-form button:hover {
    background-color: #57534e;
}

@media (min-width: 600px) {
    .contact-form {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .contact-form p:nth-child(3),
    .contact-form p:nth-child(4) {
        grid-column: 1 / -1;
    }
}

/* ================= FOOTER ================= */

.site-footer {
    padding: 48px 16px 24px;
    background-color: #292524;
    color: #d6d3d1;
}

.footer-cols {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;

    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0;

    list-style: none;
}

.footer-cols h3 {
    margin: 0 0 12px;
    color: #ffffff;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 18px;
}

.footer-cols p {
    margin: 0;
    line-height: 1.6;
    overflow-wrap: anywhere;
}

.copyright {
    width: 100%;
    max-width: 1280px;
    margin: 32px auto 0;
    padding-top: 20px;

    border-top: 1px solid #57534e;
    text-align: center;
    color: #a8a29e;
}

@media (min-width: 600px) {
    .footer-cols {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (min-width: 1024px) {
    .footer-cols {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
}

/* ================= VALUE CARDS ================= */

#gia-tri > h2 {
    display: flex;
    align-items: center;
    gap: 16px;
}

#gia-tri > h2::after {
    content: "";
    flex: 1;
    height: 1px;
    background-color: #d6d3d1;
}

.value-list {
    counter-reset: value-number;
}

.value-card {
    --accent-color: #8a5a3b;

    position: relative;
    isolation: isolate;
    overflow: hidden;

    display: flex;
    flex-direction: column;

    min-height: 210px;
    padding: clamp(24px, 3vw, 32px);

    border-color: #cec5b6;
    background:
        linear-gradient(
            145deg,
            #fffdf8 0%,
            #f1eadf 100%
        );

    transition:
        transform 200ms ease,
        border-color 200ms ease,
        box-shadow 200ms ease;
}

.value-card::after {
    content: "";

    position: absolute;
    top: 0;
    left: 0;
    right: 0;

    height: 4px;
    background-color: var(--accent-color);
}

.value-card::before {
    counter-increment: value-number;
    content: "0" counter(value-number);

    position: absolute;
    top: 10px;
    right: 16px;
    z-index: 0;

    color: rgba(112, 67, 47, 0.1);
    font-family: Georgia, "Times New Roman", serif;
    font-size: 72px;
    font-weight: 700;
    line-height: 1;
}

.value-card > * {
    position: relative;
    z-index: 1;
}

.value-card h3 {
    margin: 0 0 14px;
    font-size: 24px;
}

.value-card p {
    margin: 0;
    color: #57534e;
    line-height: 1.7;
}

.value-card:nth-child(1) {
    --accent-color: #8a5a3b;
}

.value-card:nth-child(2) {
    --accent-color: #4f6f52;
}

.value-card:nth-child(3) {
    --accent-color: #a06f3b;
}

@media (hover: hover) {
    .value-card:hover {
        transform: translateY(-4px);
        border-color: var(--accent-color);
        box-shadow: 0 14px 30px rgba(41, 37, 36, 0.12);
    }
}

/* ================= TEAM CARDS ================= */

#doi-ngu > h2 {
    display: flex;
    align-items: center;
    gap: 16px;
}

#doi-ngu > h2::after {
    content: "";
    flex: 1;
    height: 1px;
    background-color: #d6d3d1;
}

.member {
    overflow: hidden;

    display: flex;
    flex-direction: column;

    height: 100%;
    padding: 0;

    border-color: #cec5b6;
    background-color: #fffdf8;

    transition:
        transform 200ms ease,
        border-color 200ms ease,
        box-shadow 200ms ease;
}

.member img {
    width: 100%;
    aspect-ratio: 4 / 3;

    object-fit: cover;
    object-position: center 30%;

    filter: saturate(0.85);
    transition:
        transform 300ms ease,
        filter 300ms ease;
}

.member h3 {
    margin: 20px 20px 6px;
    font-size: 24px;
}

.member p {
    flex: 1;

    margin: 0;
    padding: 0 20px 24px;

    color: #78716c;
    font-size: 13px;
    font-weight: 600;
    line-height: 1.5;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}