:root {
    --primary-color: #11A84E; /* Main color */
    --secondary-color: #22C768; /* Auxiliary color */
    --button-gradient: linear-gradient(180deg, #2AD16F 0%, #13994A 100%);
    --card-bg: #11271B;
    --bg-color: #08160F; /* Main background color */
    --text-main: #F2FFF6;
    --text-secondary: #A7D9B8;
    --border: #2E7A4E;
    --glow: #57E38D;
    --gold: #F2C14E;
    --divider: #1E3A2A;
    --deep-green: #0A4B2C;
}

/* style/about.css */
/* body đã padding-top: var(--header-offset)；trang này cấm viết lại biến này */

/* Base styles for the about page */
.page-about {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-main); /* Default text color for the page */
    background-color: var(--bg-color); /* Default background color for the page */
}

.page-about__container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    box-sizing: border-box;
}

.page-about__section {
    padding: 60px 0;
    text-align: center;
}

.page-about__section-title {
    font-size: clamp(2rem, 4vw, 2.8rem); /* H1/H2 font size rule */
    color: var(--text-main);
    margin-bottom: 30px;
    font-weight: bold;
    line-height: 1.2;
    letter-spacing: -0.5px;
}

.page-about__intro-text {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto 40px auto;
}

/* Hero Section */
.page-about__hero-section {
    position: relative;
    width: 100%;
    display: flex;
    flex-direction: column; /* Enforce upper-image-lower-text */
    align-items: center;
    padding: 60px 0;
    padding-top: 10px; /* Small top padding for the first section */
    overflow: hidden; /* Ensure nothing overflows */
}

.page-about__hero-image {
    width: 100%;
    max-width: 1200px; /* Adjust based on desired display width */
    height: auto;
    display: block;
    object-fit: cover;
    margin-bottom: 40px; /* Space between image and content */
    border-radius: 10px;
}

.page-about__hero-content {
    max-width: 900px;
    text-align: center;
    padding: 0 20px;
}

.page-about__main-title {
    font-size: clamp(2.5rem, 5vw, 3.5rem); /* H1 font size rule */
    color: var(--text-main);
    margin-bottom: 20px;
    font-weight: bold;
    line-height: 1.2;
    letter-spacing: -1px;
}

.page-about__description {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.5;
}

.page-about__cta-buttons {
    display: flex;
    flex-wrap: wrap; /* Allow wrapping for mobile */
    justify-content: center;
    gap: 20px;
    margin-top: 20px;
}

/* Buttons */
.page-about__btn-primary,
.page-about__btn-secondary,
.page-about__btn-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 15px 30px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: bold;
    font-size: 1rem;
    transition: all 0.3s ease;
    box-sizing: border-box;
    max-width: 100%; /* Ensure buttons don't overflow */
    white-space: normal; /* Allow text wrapping */
    word-wrap: break-word; /* Allow text wrapping */
}

.page-about__btn-primary {
    background: linear-gradient(180deg, #2AD16F 0%, #13994A 100%);
    color: #ffffff;
    border: 2px solid transparent;
}

.page-about__btn-primary:hover {
    background: linear-gradient(180deg, #13994A 0%, #2AD16F 100%);
    box-shadow: 0 0 15px var(--glow);
}

.page-about__btn-secondary {
    background: transparent;
    color: var(--text-main);
    border: 2px solid var(--border);
}

.page-about__btn-secondary:hover {
    background: var(--border);
    color: #ffffff;
}

.page-about__btn-link {
    color: var(--gold);
    text-decoration: underline;
    background: none;
    border: none;
    padding: 5px 0;
    font-size: 0.95rem;
}

.page-about__btn-link:hover {
    color: var(--glow);
}

/* Mission & Vision / Social Responsibility Sections */
.page-about__content-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.page-about__card {
    background-color: var(--card-bg);
    border-radius: 10px;
    padding: 30px;
    text-align: left;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: flex-start;
    height: 100%; /* Ensure cards have equal height */
    box-sizing: border-box;
    color: var(--text-main); /* Ensure text color contrast */
}

.page-about__dark-bg {
    background-color: var(--deep-green); /* Use a darker custom color for specific cards */
    color: #ffffff; /* White text for dark background */
}

.page-about__dark-bg .page-about__card-title {
    color: var(--gold); /* Gold title for dark background */
}

.page-about__dark-bg .page-about__card-text {
    color: var(--text-secondary); /* Lighter secondary text for dark background */
}


.page-about__card-title {
    font-size: 1.8rem;
    color: var(--text-main);
    margin-bottom: 15px;
    font-weight: bold;
}

.page-about__card-text {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* History Section */
.page-about__history-timeline {
    position: relative;
    max-width: 900px;
    margin: 60px auto;
    padding: 0 20px;
}

.page-about__history-timeline::before {
    content: '';
    position: absolute;
    width: 2px;
    background-color: var(--divider);
    top: 0;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    z-index: 0;
}

.page-about__timeline-item {
    padding: 20px 0;
    position: relative;
    width: 50%;
    box-sizing: border-box;
}

.page-about__timeline-item:nth-child(odd) {
    left: 0;
    padding-right: 40px;
    text-align: right;
}

.page-about__timeline-item:nth-child(even) {
    left: 50%;
    padding-left: 40px;
    text-align: left;
}

.page-about__timeline-item::before {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    background-color: var(--deep-green);
    border: 2px solid var(--glow);
    border-radius: 50%;
    top: 28px;
    z-index: 1;
}

.page-about__timeline-item:nth-child(odd)::before {
    right: -8px;
}

.page-about__timeline-item:nth-child(even)::before {
    left: -8px;
}

.page-about__timeline-year {
    font-size: 1.4rem;
    font-weight: bold;
    color: var(--gold);
    margin-bottom: 10px;
}

.page-about__timeline-description {
    font-size: 1rem;
    color: var(--text-secondary);
}

.page-about__image-centered {
    width: 100%;
    max-width: 800px;
    height: auto;
    display: block;
    margin: 40px auto;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

/* Why Choose Section */
.page-about__advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.page-about__advantage-item {
    background-color: var(--card-bg); /* Use card background color */
    border-radius: 10px;
    padding: 30px;
    text-align: left;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    height: 100%;
    box-sizing: border-box;
    color: var(--text-main); /* Ensure text color contrast */
}

.page-about__light-bg {
    background-color: #0d1a13; /* A slightly lighter dark background for contrast */
    color: #ffffff;
}

.page-about__light-bg .page-about__advantage-title {
    color: var(--gold);
}

.page-about__light-bg .page-about__advantage-description {
    color: var(--text-secondary);
}

.page-about__advantage-title {
    font-size: 1.6rem;
    color: var(--text-main);
    margin-bottom: 15px;
    font-weight: bold;
}

.page-about__advantage-description {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 20px;
    flex-grow: 1; /* Push image to bottom if content varies */
}

.page-about__advantage-image {
    width: 100%;
    max-width: 600px; /* Adjust based on display width */
    height: auto;
    display: block;
    margin-top: auto; /* Push image to the bottom */
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

/* Future Section */
.page-about__future-list {
    list-style: none;
    padding: 0;
    margin-top: 40px;
    text-align: left;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.page-about__future-item {
    background-color: var(--card-bg);
    border-radius: 10px;
    padding: 30px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    color: var(--text-main);
}

.page-about__list-title {
    font-size: 1.5rem;
    color: var(--gold);
    margin-bottom: 10px;
    font-weight: bold;
}

.page-about__future-item p {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* FAQ Section */
.page-about__faq {
    background-color: var(--bg-color); /* Ensure contrast */
}

.page-about__faq-list {
    max-width: 900px;
    margin: 40px auto 0 auto;
    text-align: left;
}

.page-about__faq-item {
    background-color: var(--card-bg);
    border-radius: 8px;
    margin-bottom: 15px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    border: 1px solid var(--border);
}

.page-about__faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 25px;
    font-size: 1.1rem;
    font-weight: bold;
    color: var(--text-main);
    cursor: pointer;
    background-color: var(--deep-green); /* Darker background for question */
    border-radius: 8px;
    transition: background-color 0.3s ease;
}

.page-about__faq-question:hover {
    background-color: var(--primary-color); /* Use primary color on hover */
}

.page-about__faq-question::-webkit-details-marker,
.page-about__faq-question::marker {
    display: none; /* Hide default marker for summary */
}

.page-about__faq-toggle {
    font-size: 1.5rem;
    line-height: 1;
    color: var(--gold);
}

.page-about__faq-answer {
    padding: 15px 25px 20px;
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
    background-color: var(--card-bg);
    border-bottom-left-radius: 8px;
    border-bottom-right-radius: 8px;
}

.page-about__faq-answer p {
    margin-bottom: 15px;
}

.page-about__faq-answer a {
    display: inline-block;
    margin-top: 10px;
}

/* Bottom CTA Section */
.page-about__cta-bottom {
    background-color: var(--deep-green);
    padding: 80px 0;
}

.page-about__cta-bottom .page-about__container {
    background-color: var(--card-bg);
    padding: 50px;
    border-radius: 15px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4);
}

.page-about__cta-bottom .page-about__section-title {
    color: var(--gold);
}

.page-about__cta-bottom .page-about__description {
    color: var(--text-secondary);
}

/* Global image styles (applying to all images within .page-about) */
.page-about img {
    max-width: 100%;
    height: auto;
    display: block;
    /* Ensure no filter is applied */
    filter: none;
}

/* Responsive styles */
@media (max-width: 992px) {
    .page-about__history-timeline::before {
        left: 20px;
        transform: translateX(0);
    }

    .page-about__timeline-item {
        width: 100%;
        left: 0;
        padding-left: 40px;
        padding-right: 20px;
        text-align: left;
    }

    .page-about__timeline-item:nth-child(odd) {
        padding-right: 20px;
    }

    .page-about__timeline-item:nth-child(odd)::before,
    .page-about__timeline-item:nth-child(even)::before {
        left: 12px;
        right: auto;
    }
}

@media (max-width: 768px) {
    .page-about__section {
        padding: 40px 0;
    }

    .page-about__main-title {
        font-size: clamp(2rem, 8vw, 2.5rem);
    }

    .page-about__section-title {
        font-size: clamp(1.8rem, 7vw, 2.2rem);
    }

    .page-about__description,
    .page-about__intro-text {
        font-size: 1rem;
    }

    .page-about__cta-buttons {
        flex-direction: column;
        gap: 15px;
    }

    .page-about__btn-primary,
    .page-about__btn-secondary,
    .page-about__btn-link {
        width: 100% !important;
        max-width: 100% !important;
        padding: 12px 20px;
        font-size: 0.95rem;
    }

    /* Images responsiveness */
    .page-about img {
        max-width: 100% !important;
        width: 100% !important;
        height: auto !important;
        display: block !important;
    }
    
    .page-about__section,
    .page-about__card,
    .page-about__container,
    .page-about__hero-section,
    .page-about__history-timeline,
    .page-about__advantages-grid,
    .page-about__future-list,
    .page-about__faq-list,
    .page-about__cta-bottom .page-about__container {
        max-width: 100% !important;
        width: 100% !important;
        box-sizing: border-box !important;
        padding-left: 15px !important;
        padding-right: 15px !important;
        overflow: hidden !important; /* Ensure no overflow */
    }

    .page-about__hero-section {
        padding-top: 10px !important; /* body already handles --header-offset */
    }

    .page-about__faq-question {
        font-size: 1rem;
        padding: 15px 20px;
    }
    .page-about__faq-answer {
        padding: 10px 20px 15px;
        font-size: 0.95rem;
    }
}