/* Variables */
:root {
    --main-color: #113B7A;
    --accent-color: #1D5FD1;
    --button-gradient: linear-gradient(180deg, #2B73F6 0%, #1144A6 100%);
    --card-bg-color: #10233F;
    --text-main: #F3F8FF;
    --text-secondary: #AFC4E8;
    --border-color: #244D84;
    --glow-color: #4FA8FF;
    --gold-color: #F2C14E;
    --divider-color: #1B3357;
    --deep-navy-color: #08162B;
}

/* Base styles for the page */
.page-khuyen-mai {
    background-color: var(--deep-navy-color); /* Matches body background */
    color: var(--text-main); /* Light text for dark background */
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    font-size: 16px;
}

/* Hero Section */
.page-khuyen-mai__hero-section {
    position: relative;
    padding-top: 10px; /* Small top padding as per rules, relies on body padding-top */
    margin-bottom: 40px;
    text-align: center;
}

.page-khuyen-mai__hero-image {
    width: 100%;
    height: auto;
    display: block;
    object-fit: cover;
    max-height: 600px; /* Limit height for hero image */
    min-width: 200px;
    min-height: 200px;
}

.page-khuyen-mai__hero-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 40px 20px;
    text-align: center;
    background: rgba(16, 35, 63, 0.8); /* Card BG color with transparency */
    border-radius: 10px;
    transform: translateY(-50px); /* Slightly overlap the image for visual effect */
    position: relative;
    z-index: 1;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    border: 1px solid var(--border-color);
}

.page-khuyen-mai__main-title {
    font-size: clamp(2.2em, 4vw, 3.2em); /* Use clamp for H1 font-size */
    color: var(--gold-color);
    margin-bottom: 15px;
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: 0.05em;
    text-shadow: 0 0 10px rgba(242, 193, 78, 0.5); /* Subtle glow */
}

.page-khuyen-mai__hero-description {
    font-size: 1.1em;
    color: var(--text-secondary);
    margin-bottom: 30px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.page-khuyen-mai__hero-cta {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.page-khuyen-mai__btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1em;
    transition: all 0.3s ease;
    cursor: pointer;
    text-align: center;
    box-sizing: border-box;
    max-width: 100%; /* Ensure responsiveness */
    white-space: normal;
    word-wrap: break-word;
}

.page-khuyen-mai__btn--primary {
    background: var(--button-gradient);
    color: #ffffff;
    border: 2px solid transparent;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
}

.page-khuyen-mai__btn--primary:hover {
    background: linear-gradient(180deg, #1144A6 0%, #2B73F6 100%);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
}

.page-khuyen-mai__btn--secondary {
    background-color: transparent;
    color: var(--glow-color);
    border: 2px solid var(--glow-color);
    box-shadow: 0 0 10px rgba(79, 168, 255, 0.3);
}

.page-khuyen-mai__btn--secondary:hover {
    background-color: var(--glow-color);
    color: var(--deep-navy-color);
    box-shadow: 0 0 15px rgba(79, 168, 255, 0.5);
}

/* Sections and Containers */
.page-khuyen-mai__section {
    padding: 50px 0;
    margin-bottom: 20px;
}

.page-khuyen-mai__container {
    max-width: 1150px;
    margin: 0 auto;
    padding: 0 20px;
}

.page-khuyen-mai__container--center {
    text-align: center;
}

.page-khuyen-mai__section-title {
    font-size: 2.5em;
    color: var(--gold-color);
    text-align: center;
    margin-bottom: 40px;
    font-weight: 700;
    line-height: 1.3;
    text-shadow: 0 0 8px rgba(242, 193, 78, 0.4);
}

.page-khuyen-mai__text-block {
    font-size: 1.05em;
    color: var(--text-secondary);
    margin-bottom: 20px;
    text-align: justify;
}

.page-khuyen-mai__text-block--callout {
    font-size: 1.15em;
    font-weight: 600;
    color: var(--glow-color);
    text-align: center;
    margin-top: 40px;
    padding: 20px;
    background-color: var(--card-bg-color);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.page-khuyen-mai__text-block--note {
    font-style: italic;
    font-size: 0.95em;
    color: var(--text-secondary);
    text-align: center;
    margin-top: 30px;
    padding: 15px;
    background-color: var(--card-bg-color);
    border-left: 5px solid var(--glow-color);
    border-radius: 5px;
}

.page-khuyen-mai__content-image {
    width: 100%;
    height: auto;
    display: block;
    margin: 30px auto;
    border-radius: 8px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.4);
    min-width: 200px; /* Minimum size requirement */
    min-height: 200px;
}

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

.page-khuyen-mai__promo-card {
    background-color: var(--card-bg-color);
    border-radius: 10px;
    padding: 25px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
    text-align: center;
    border: 1px solid var(--border-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.page-khuyen-mai__promo-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.4);
}

.page-khuyen-mai__card-image {
    width: 100%;
    height: 200px; /* Fixed height for consistency */
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 20px;
    min-width: 200px; /* Minimum size requirement */
    min-height: 200px;
}

.page-khuyen-mai__card-title {
    font-size: 1.5em;
    color: var(--text-main);
    margin-bottom: 15px;
    font-weight: 600;
}

.page-khuyen-mai__card-description {
    font-size: 0.95em;
    color: var(--text-secondary);
    margin-bottom: 20px;
    flex-grow: 1; /* Allow description to take available space */
}

.page-khuyen-mai__btn--small {
    padding: 8px 20px;
    font-size: 0.9em;
    margin-top: auto; /* Push button to bottom */
}

/* How to Get Section */
.page-khuyen-mai__steps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.page-khuyen-mai__step-card {
    background-color: var(--card-bg-color);
    border-radius: 10px;
    padding: 30px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
    text-align: center;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
}

.page-khuyen-mai__step-number {
    font-size: 2.5em;
    font-weight: 700;
    color: var(--gold-color);
    margin-bottom: 15px;
    background: var(--deep-navy-color);
    border-radius: 50%;
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--gold-color);
    box-shadow: 0 0 15px rgba(242, 193, 78, 0.5);
}

.page-khuyen-mai__step-title {
    font-size: 1.4em;
    color: var(--text-main);
    margin-bottom: 10px;
    font-weight: 600;
}

.page-khuyen-mai__step-description {
    font-size: 0.95em;
    color: var(--text-secondary);
    margin-bottom: 20px;
    flex-grow: 1;
}

.page-khuyen-mai__btn--link {
    background: none;
    border: none;
    color: var(--glow-color);
    text-decoration: underline;
    padding: 0;
    font-size: 0.95em;
    margin-top: auto;
}

.page-khuyen-mai__btn--link:hover {
    color: #fff;
    text-decoration: none;
}

/* Terms and Conditions Section */
.page-khuyen-mai__terms-list {
    list-style: none;
    padding: 0;
    margin-top: 40px;
}

.page-khuyen-mai__terms-item {
    background-color: var(--card-bg-color);
    border-radius: 8px;
    padding: 25px;
    margin-bottom: 20px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    border-left: 5px solid var(--main-color);
}

.page-khuyen-mai__terms-heading {
    font-size: 1.3em;
    color: var(--text-main);
    margin-bottom: 10px;
    font-weight: 600;
}

.page-khuyen-mai__terms-description {
    font-size: 1em;
    color: var(--text-secondary);
    text-align: justify;
}

.page-khuyen-mai__text-block--warning {
    font-size: 1.1em;
    font-weight: 500;
    color: var(--gold-color);
    text-align: center;
    margin-top: 40px;
    padding: 20px;
    background-color: #10233F; /* Slightly darker card bg */
    border-radius: 8px;
    border: 1px solid var(--gold-color);
    box-shadow: 0 0 15px rgba(242, 193, 78, 0.3);
}

/* FAQ Section */
.page-khuyen-mai__faq-list {
    margin-top: 40px;
}

.page-khuyen-mai__faq-item {
    background-color: var(--card-bg-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 15px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
}

.page-khuyen-mai__faq-item[open] {
    background-color: #1a3050; /* Slightly lighter when open */
    border-color: var(--main-color);
}

.page-khuyen-mai__faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 25px;
    cursor: pointer;
    font-size: 1.2em;
    font-weight: 600;
    color: var(--text-main);
    list-style: none; /* Hide default marker */
}

.page-khuyen-mai__faq-question::-webkit-details-marker,
.page-khuyen-mai__faq-question::marker {
    display: none;
    content: "";
}

.page-khuyen-mai__faq-qtext {
    flex-grow: 1;
}

.page-khuyen-mai__faq-toggle {
    font-size: 1.5em;
    color: var(--glow-color);
    margin-left: 15px;
    transition: transform 0.3s ease;
}

.page-khuyen-mai__faq-item[open] .page-khuyen-mai__faq-toggle {
    transform: rotate(45deg); /* Change to X or rotate + */
}

.page-khuyen-mai__faq-answer {
    padding: 0 25px 20px;
    font-size: 1em;
    color: var(--text-secondary);
    text-align: justify;
}

.page-khuyen-mai__faq-answer p {
    margin-bottom: 10px;
}

.page-khuyen-mai__faq-cta {
    margin-top: 20px;
    text-align: center;
}

/* Call to Action Section */
.page-khuyen-mai__cta-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-top: 30px;
    flex-wrap: wrap;
    width: 100%;
    max-width: 100%;
    box-sizing: border-box;
    overflow: hidden;
}

/* --- Responsive Styles --- */

/* Tablet and Mobile (max-width: 1024px) */
@media (max-width: 1024px) {
    .page-khuyen-mai__main-title {
        font-size: clamp(2em, 5vw, 2.8em);
    }

    .page-khuyen-mai__hero-description {
        font-size: 1em;
    }

    .page-khuyen-mai__section-title {
        font-size: 2em;
    }

    .page-khuyen-mai__promo-grid,
    .page-khuyen-mai__steps-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 25px;
    }

    .page-khuyen-mai__promo-card,
    .page-khuyen-mai__step-card {
        padding: 20px;
    }

    .page-khuyen-mai__card-image {
        height: 180px;
    }

    .page-khuyen-mai__terms-item {
        padding: 20px;
    }
}

/* Mobile (max-width: 768px) - Must include all required sections */
@media (max-width: 768px) {
    /* 1. Top section title + dual CTA */
    .page-khuyen-mai__hero-section {
        padding-top: 10px !important; /* Small top padding for mobile */
        margin-bottom: 20px;
    }

    .page-khuyen-mai__hero-content {
        padding: 30px 15px;
        transform: translateY(-30px);
        margin: 0 15px; /* Adjust margin to fit screen */
    }

    .page-khuyen-mai__main-title {
        font-size: clamp(1.8em, 7vw, 2.5em) !important; /* Smaller H1 for mobile */
        margin-bottom: 10px;
    }

    .page-khuyen-mai__hero-description {
        font-size: 0.95em;
        margin-bottom: 20px;
    }

    .page-khuyen-mai__hero-cta {
        flex-direction: column; /* Stack buttons vertically */
        gap: 10px;
        padding: 0 15px; /* Add padding to button container */
        box-sizing: border-box;
        width: 100%;
    }

    /* 4. Buttons and button containers */
    .page-khuyen-mai__btn,
    .page-khuyen-mai__btn--primary,
    .page-khuyen-mai__btn--secondary,
    .page-khuyen-mai a[class*="button"],
    .page-khuyen-mai a[class*="btn"] {
        max-width: 100% !important;
        width: 100% !important;
        box-sizing: border-box !important;
        white-space: normal !important;
        word-wrap: break-word !important;
        padding-left: 15px;
        padding-right: 15px;
    }

    .page-khuyen-mai__cta-buttons,
    .page-khuyen-mai__button-group,
    .page-khuyen-mai__btn-container {
        max-width: 100% !important;
        width: 100% !important;
        box-sizing: border-box !important;
        padding-left: 15px;
        padding-right: 15px;
        flex-wrap: wrap !important; /* Ensure multiple buttons wrap */
        gap: 10px;
        flex-direction: column; /* Stack buttons in final CTA */
    }

    /* 2. Single-column long article container (applies to all sections) */
    .page-khuyen-mai__section {
        padding: 30px 0;
    }

    .page-khuyen-mai__container {
        padding: 0 15px !important; /* Consistent padding for content */
        max-width: 100% !important;
        width: 100% !important;
        box-sizing: border-box !important;
    }

    .page-khuyen-mai__section-title {
        font-size: 1.8em;
        margin-bottom: 30px;
    }

    .page-khuyen-mai__text-block {
        font-size: 1em;
    }

    .page-khuyen-mai__text-block--callout,
    .page-khuyen-mai__text-block--note,
    .page-khuyen-mai__text-block--warning {
        font-size: 1em;
        padding: 15px;
    }

    /* 3. Generic images and figure */
    .page-khuyen-mai img {
        max-width: 100% !important;
        width: 100% !important;
        height: auto !important;
        min-width: 200px !important; /* Enforce min size even on mobile */
        min-height: 200px !important;
    }

    .page-khuyen-mai__promo-grid,
    .page-khuyen-mai__steps-grid {
        grid-template-columns: 1fr; /* Single column layout */
        gap: 20px;
    }

    .page-khuyen-mai__promo-card {
        padding: 20px;
    }

    .page-khuyen-mai__card-image {
        height: auto; /* Allow auto height for card images */
        max-height: 250px; /* Max height to prevent overly tall images */
    }

    .page-khuyen-mai__step-card {
        padding: 25px;
    }

    .page-khuyen-mai__terms-item {
        padding: 20px;
        border-left-width: 3px;
    }

    .page-khuyen-mai__terms-heading {
        font-size: 1.2em;
    }

    .page-khuyen-mai__faq-question {
        font-size: 1.1em;
        padding: 15px 20px;
    }

    .page-khuyen-mai__faq-answer {
        padding: 0 20px 15px;
    }

    /* 5. Registration tutorial and FAQ blocks (implicitly covered by generic section/container/text/image rules) */
    /* FAQ specific adjustments for mobile already handled by .page-khuyen-mai__faq-question and .page-khuyen-mai__faq-answer */
}