@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@900&display=swap');
:root {
    /* Brand Colors */
    --primary: #FF003C;       /* Crimson Red */
    --primary-glow: rgba(255, 0, 60, 0.4);
    --secondary: #FFCE00;     /* Gold Accent */
    --bg-dark: #080808;       /* Obsidian Base */
    --bg-surface: #0e0e0e;    /* Card Surface */
    
    /* Text Colors */
    --text-high: #FFFFFF;
    --text-med: #B0B0B0;
    --text-low: #606060;
    
    /* Spacing & Safety */
    --safe-padding: clamp(20px, 8vw, 40px); /* Responsive 1cm area */
    --section-gap: clamp(80px, 15vh, 160px);
    
    /* Animation */
    --ease-out-expo: cubic-bezier(0.19, 1, 0.22, 1);
    --ease-in-out-quad: cubic-bezier(0.45, 0, 0.55, 1);
}

/* --- Global Resets --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-font-smoothing: antialiased;
}

html {
    scroll-behavior: smooth;
    background-color: var(--bg-dark);
}

body {
    font-family: 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text-med);
    line-height: 1.6;
    overflow-x: hidden;
}

/* --- Advanced Background Mesh --- */
.app-bg {
    position: fixed;
    inset: 0;
    z-index: -1;
    background: var(--bg-dark);
    overflow: hidden;
}

.mesh-glow {
    position: absolute;
    width: 80vw;
    height: 80vw;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.15;
    pointer-events: none;
    transition: transform 0.8s var(--ease-out-expo);
}

.glow-top { top: -20%; right: -10%; background: var(--primary); }
.glow-mid { top: 40%; left: -20%; background: var(--secondary); opacity: 0.08; }
.glow-bottom { bottom: -10%; right: 10%; background: var(--primary); }

/* --- Typography System --- */
h1, h2, h3 {
    color: var(--text-high);
    text-transform: uppercase;
    letter-spacing: -0.04em;
    line-height: 0.95;
    font-weight: 900;
}

.gradient-text {
    background: linear-gradient(to right, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section-label {
    display: inline-block;
    font-family: 'Montserrat', sans-serif;
    font-size: 14px;
    font-weight: 800;
    letter-spacing: 0.25em;
    color: var(--primary);
    margin-bottom: 16px;
    text-shadow: 0 0 10px var(--primary-glow);
}

/* --- Layout Architecture --- */
.container {
    max-width: 1300px;
    margin: 0 auto;
    padding-inline: var(--safe-padding);
}

section {
    position: relative;
    padding: var(--section-gap) 0;
}

/* --- Component Master: Glass Card --- */
.glass-panel {
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.01) 100%);
    border: 1px solid rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(20px);
    border-radius: 32px;
    transition: all 0.5s var(--ease-out-expo);
}

.glass-panel:hover {
    border-color: rgba(255, 255, 255, 0.15);
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.08) 0%, rgba(255, 255, 255, 0.02) 100%);
    transform: translateY(-8px);
}

/* --- Hero Redesign --- */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 60px;
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 80px;
    align-items: center;
}

.hero h1 {
    font-size: clamp(48px, 8vw, 100px);
    margin-bottom: 24px;
}

.hero p {
    font-size: clamp(18px, 2vw, 22px);
    max-width: 550px;
    margin-bottom: 48px;
    color: var(--text-med);
}

.hero-meta-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    margin-bottom: 48px;
}

.meta-item-box {
    padding: 20px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 20px;
    display: flex;
    flex-direction: column;
}

.meta-val { color: var(--text-high); font-weight: 800; font-size: 20px; }
.meta-lab { font-size: 12px; text-transform: uppercase; color: var(--text-low); }

.hero-image-wrapper {
    position: relative;
}

.hero-image-wrapper img {
    width: 100%;
    filter: drop-shadow(0 0 40px var(--primary-glow));
    animation: floatHero 8s infinite ease-in-out;
}

/* Scroll Cue */
.scroll-cue {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    opacity: 0.6;
}

.scroll-line {
    width: 1px;
    height: 60px;
    background: linear-gradient(to bottom, var(--primary), transparent);
    animation: lineScroll 2s infinite;
}

/* --- Section Bridges --- */
.section-connection {
    position: absolute;
    top: 0; left: 50%;
    transform: translate(-50%, -50%);
    width: 2px;
    height: 100px;
    background: linear-gradient(to bottom, transparent, var(--primary), transparent);
    opacity: 0.3;
}

/* --- Feature Grid --- */
.features-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
}

.rule-card {
    padding: 40px;
    position: relative;
    overflow: hidden;
}

.rule-number {
    position: absolute;
    top: -20px; right: -20px;
    font-size: 120px;
    font-weight: 900;
    color: rgba(255, 255, 255, 0.02);
    line-height: 1;
}

/* --- Payment Section --- */
.payment-grid {
    display: grid;
    grid-template-columns: 1fr 400px;
    gap: 40px;
}

.bank-info-panel {
    padding: 60px;
}

.qr-panel {
    padding: 30px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.qr-box {
    background: white;
    padding: 24px;
    border-radius: 24px;
    margin: 24px 0;
}

/* --- FAQ Accordion Modern --- */
.faq-stack {
    max-width: 900px;
    margin: 0 auto;
}

.faq-item {
    margin-bottom: 16px;
}

.faq-trigger {
    width: 100%;
    padding: 24px 32px;
    background: transparent;
    border: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-high);
    font-weight: 700;
    font-size: 18px;
    cursor: pointer;
}

.faq-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s var(--ease-out-expo);
    padding: 0 32px;
    color: var(--text-med);
}

.faq-item.active .faq-content {
    max-height: 300px;
    padding-bottom: 24px;
}

.faq-item.active {
    background: rgba(255, 255, 255, 0.03);
}

/* --- Reward/Punish Switch --- */
.logic-columns {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

.logic-card {
    padding: 50px;
    border-radius: 40px;
}

.logic-card.gain { border-top: 6px solid #00F2EA; }
.logic-card.loss { border-top: 6px solid var(--primary); }

/* --- Forms & Buttons --- */
.submit-area {
    max-width: 700px;
    margin: 0 auto;
    padding: 80px 40px;
}

.input-field {
    width: 100%;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    height: 64px;
    border-radius: 18px;
    padding: 0 24px;
    color: white;
    font-size: 16px;
    margin-bottom: 20px;
    transition: 0.3s;
}

.input-field:focus {
    border-color: var(--secondary);
    background: rgba(255, 255, 255, 0.08);
    outline: none;
}

.btn-luxury {
    width: 100%;
    height: 70px;
    background: linear-gradient(135deg, var(--primary), #D00030);
    color: white;
    border: none;
    border-radius: 20px;
    font-size: 20px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    cursor: pointer;
    box-shadow: 0 20px 40px -10px var(--primary-glow);
    transition: 0.4s var(--ease-out-expo);
}

.btn-luxury:hover {
    transform: translateY(-5px) scale(1.02);
    box-shadow: 0 30px 60px -10px var(--primary-glow);
}

/* --- Floating Zalo Modern --- */
.zalo-float {
    position: fixed;
    bottom: 40px; right: 40px;
    width: 64px; height: 64px;
    background: #0068FF;
    border-radius: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 28px;
    box-shadow: 0 15px 30px rgba(0, 104, 255, 0.4);
    z-index: 999;
}

/* --- Mobile Expert Fixes --- */
@media (max-width: 991px) {
    .hero-grid, .payment-grid, .logic-columns {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .hero h1 { line-height: 0.9; }
    .hero p { margin-inline: auto; }
    .hero-meta-grid { margin-bottom: 30px; }
}

/* --- Animations --- */
@keyframes floatHero {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-30px); }
}

@keyframes lineScroll {
    0% { transform: scaleY(0); transform-origin: top; }
    50% { transform: scaleY(1); transform-origin: top; }
    51% { transform: scaleY(1); transform-origin: bottom; }
    100% { transform: scaleY(0); transform-origin: bottom; }
}

/* --- Branding & Nav --- */
.header-nav {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: 80px;
    z-index: 1000;
    background: rgba(8, 8, 8, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.nav-container {
    max-width: 1300px;
    height: 100%;
    margin: 0 auto;
    padding-inline: var(--safe-padding);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-tanlab {
    font-family: 'Montserrat', sans-serif;
    font-weight: 900;
    font-size: 28px;
    letter-spacing: -1px;
    color: white;
    text-decoration: none;
}

/* --- Hero Expert Sync --- */
.hero-image-wrapper img {
    width: 100%;
    filter: drop-shadow(0 0 60px var(--primary-glow));
    animation: floatHero 8s infinite ease-in-out;
}

/* --- Footer Redesign --- */
.main-footer {
    background: #000;
    padding: 100px 0 40px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-brand h4 {
    margin-bottom: 20px;
    color: var(--secondary);
    font-size: 14px;
    letter-spacing: 2px;
}

.footer-social-links {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

.social-icon {
    width: 44px;
    height: 44px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    font-size: 20px;
    transition: 0.3s;
}

.social-icon:hover {
    background: var(--primary);
    transform: translateY(-3px);
}

.footer-links-col h4 {
    color: white;
    margin-bottom: 25px;
    font-size: 16px;
}

.footer-links-col ul {
    list-style: none;
}

.footer-links-col li {
    margin-bottom: 12px;
}

.footer-links-col a {
    color: var(--text-med);
    text-decoration: none;
    font-size: 14px;
    transition: 0.3s;
}

.footer-links-col a:hover {
    color: var(--secondary);
}

.footer-bottom {
    padding-top: 40px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-copyright {
    font-size: 13px;
    color: var(--text-low);
}

.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: all 1s var(--ease-out-expo);
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

@media (max-width: 991px) {
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }
    .footer-social-links {
        justify-content: center;
    }
    .footer-bottom {
        justify-content: center;
        text-align: center;
    }
}