/* ========================================
   Messlỏ Landing Page — Theme
   ======================================== */

:root {
    --primary: #0084ff;
    --primary-glow: rgba(0, 132, 255, 0.15);
    --accent: #a033ff;
    --bg: #050510;
    --bg-card: rgba(255, 255, 255, 0.04);
    --bg-card-hover: rgba(255, 255, 255, 0.08);
    --text: #f0f0f5;
    --text-sec: #8a8a9a;
    --border: rgba(255, 255, 255, 0.08);
    --border-hover: rgba(255, 255, 255, 0.15);
    --green: #00d26a;
    --radius: 16px;
    --radius-lg: 24px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 80px; }

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    overflow-x: hidden;
}

.container { max-width: 1140px; margin: 0 auto; padding: 0 24px; }

/* ---- Animated Background Glows ---- */
.bg-glow {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.3;
    pointer-events: none;
    z-index: -1;
}
.bg-glow-1 {
    width: 600px; height: 600px;
    background: var(--primary);
    top: -200px; left: -100px;
    animation: glowFloat 12s ease-in-out infinite alternate;
}
.bg-glow-2 {
    width: 500px; height: 500px;
    background: var(--accent);
    bottom: -200px; right: -100px;
    animation: glowFloat 15s ease-in-out infinite alternate-reverse;
}
@keyframes glowFloat {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(60px, 40px) scale(1.1); }
}

/* ---- Navigation ---- */
nav {
    position: fixed; top: 0; left: 0; right: 0;
    z-index: 1000;
    background: rgba(5, 5, 16, 0.7);
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    transition: all 0.3s ease;
}
nav.scrolled { background: rgba(5, 5, 16, 0.95); }

.nav-inner {
    max-width: 1140px; margin: 0 auto;
    display: flex; align-items: center; justify-content: space-between;
    padding: 16px 24px;
}

.logo {
    display: flex; align-items: center; gap: 10px;
    text-decoration: none; color: var(--text);
    font-size: 1.2rem; font-weight: 800;
}
.logo img { width: 30px; height: 30px; border-radius: 8px; }

.nav-links {
    display: flex; gap: 32px; list-style: none;
}
.nav-links a {
    text-decoration: none; color: var(--text-sec);
    font-size: 0.9rem; font-weight: 500;
    transition: color 0.2s;
}
.nav-links a:hover { color: var(--text); }

.nav-actions { display: flex; align-items: center; gap: 16px; }

.btn-nav {
    text-decoration: none; color: var(--text);
    background: rgba(255,255,255,0.08);
    padding: 8px 18px; border-radius: 10px;
    font-size: 0.85rem; font-weight: 600;
    border: 1px solid var(--border);
    transition: all 0.2s;
    display: flex; align-items: center; gap: 8px;
}
.btn-nav:hover { background: rgba(255,255,255,0.14); border-color: var(--border-hover); }

.hamburger {
    display: none; flex-direction: column; gap: 5px;
    background: none; border: none; cursor: pointer; padding: 4px;
}
.hamburger span {
    width: 22px; height: 2px; background: var(--text);
    border-radius: 2px; transition: all 0.3s;
}

/* ---- Hero ---- */
.hero {
    padding: 140px 0 80px;
    min-height: 100vh;
    display: flex; align-items: center;
}

.hero-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px; align-items: center;
}

.version-pill {
    display: inline-flex; align-items: center; gap: 8px;
    background: var(--primary-glow);
    color: var(--primary);
    padding: 6px 16px; border-radius: 100px;
    font-size: 0.8rem; font-weight: 700;
    margin-bottom: 24px;
    border: 1px solid rgba(0, 132, 255, 0.2);
}
.pulse-dot {
    width: 8px; height: 8px;
    background: var(--green);
    border-radius: 50%;
    animation: pulse 2s infinite;
}
@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(1.3); }
}

.hero-content h1 {
    font-size: 3.4rem; line-height: 1.15;
    font-weight: 900; margin-bottom: 20px;
    letter-spacing: -0.02em;
}
.gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    color: var(--text-sec); font-size: 1.1rem;
    margin-bottom: 32px; max-width: 480px;
}

.hero-stats {
    display: flex; align-items: center; gap: 28px;
    margin-bottom: 40px;
}
.stat { text-align: center; }
.stat-number { display: block; font-size: 1.5rem; font-weight: 800; color: var(--text); }
.stat-label { font-size: 0.75rem; color: var(--text-sec); font-weight: 500; text-transform: uppercase; letter-spacing: 0.05em; }
.stat-divider { width: 1px; height: 36px; background: var(--border); }

.cta-group { display: flex; gap: 16px; flex-wrap: wrap; }

.btn-primary {
    background: linear-gradient(135deg, var(--primary), #0060cc);
    color: white; padding: 14px 32px;
    border-radius: 12px; text-decoration: none;
    font-weight: 700; font-size: 0.95rem;
    display: inline-flex; align-items: center; gap: 10px;
    transition: all 0.3s; border: none;
    box-shadow: 0 4px 24px rgba(0, 132, 255, 0.3);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 32px rgba(0, 132, 255, 0.4); }

.btn-outline {
    background: transparent; color: var(--text);
    padding: 14px 28px; border-radius: 12px;
    text-decoration: none; font-weight: 600; font-size: 0.95rem;
    border: 1px solid var(--border);
    display: inline-flex; align-items: center; gap: 10px;
    transition: all 0.3s;
}
.btn-outline:hover { background: rgba(255,255,255,0.06); border-color: var(--border-hover); }

.btn-large { padding: 18px 40px; font-size: 1.05rem; }

/* ---- App Preview (Hero Right) ---- */
.hero-visual { position: relative; }

.app-preview {
    background: rgba(20, 20, 40, 0.8);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.preview-titlebar {
    display: flex; align-items: center; gap: 12px;
    padding: 14px 18px;
    background: rgba(255,255,255,0.03);
    border-bottom: 1px solid var(--border);
}
.titlebar-dots { display: flex; gap: 6px; }
.dot { width: 10px; height: 10px; border-radius: 50%; }
.dot-red { background: #ff5f57; }
.dot-yellow { background: #febc2e; }
.dot-green { background: #28c840; }
.titlebar-text { font-size: 0.8rem; color: var(--text-sec); font-weight: 600; margin-left: auto; }

.preview-body { padding: 0; }

/* Messenger-specific preview */
.messenger-preview { padding: 0; }

.msg-sidebar { display: flex; flex-direction: column; }

.msg-contact {
    display: flex; align-items: center; gap: 12px;
    padding: 14px 18px;
    border-bottom: 1px solid var(--border);
    transition: background 0.2s;
}
.msg-contact.active { background: rgba(0, 132, 255, 0.08); }
.msg-contact:last-child { border-bottom: none; }

.msg-avatar {
    width: 40px; height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    display: flex; align-items: center; justify-content: center;
    color: white; font-size: 0.9rem;
    flex-shrink: 0;
}

.msg-info { flex: 1; min-width: 0; }
.msg-name { font-size: 0.85rem; font-weight: 700; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.msg-last { font-size: 0.75rem; color: var(--text-sec); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; margin-top: 2px; }

.msg-badge {
    background: var(--primary);
    color: white;
    font-size: 0.65rem; font-weight: 800;
    width: 20px; height: 20px;
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
}

.preview-footer {
    padding: 10px 18px; font-size: 0.7rem;
    color: var(--text-sec); text-align: center;
    border-top: 1px solid var(--border);
    background: rgba(255,255,255,0.02);
    display: flex; align-items: center; justify-content: center; gap: 6px;
}

/* ---- Section Headers ---- */
.section-header {
    text-align: center; margin-bottom: 60px;
}
.section-badge {
    display: inline-block;
    background: var(--primary-glow);
    color: var(--primary);
    padding: 4px 14px; border-radius: 100px;
    font-size: 0.75rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.08em;
    margin-bottom: 16px;
    border: 1px solid rgba(0, 132, 255, 0.15);
}
.section-header h2 {
    font-size: 2.4rem; font-weight: 800;
    margin-bottom: 12px;
}
.section-header p {
    color: var(--text-sec); font-size: 1.05rem;
    max-width: 520px; margin: 0 auto;
}

/* ---- Features Grid ---- */
.features { padding: 100px 0; }

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    transition: all 0.3s;
}
.feature-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
}

.feature-icon {
    width: 48px; height: 48px;
    background: var(--primary-glow);
    border-radius: 14px;
    display: flex; align-items: center; justify-content: center;
    margin-bottom: 20px;
    font-size: 1.2rem; color: var(--primary);
}

.feature-card h3 {
    font-size: 1.1rem; font-weight: 700;
    margin-bottom: 8px;
}
.feature-card p {
    color: var(--text-sec); font-size: 0.9rem; line-height: 1.6;
}
.feature-card code {
    background: rgba(255,255,255,0.08);
    padding: 2px 6px; border-radius: 4px;
    font-size: 0.85rem;
}

/* ---- Install Steps ---- */
.install { padding: 100px 0; }

.steps-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px; margin-bottom: 48px;
}
.step-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    text-align: center;
    transition: all 0.3s;
}
.step-card:hover { background: var(--bg-card-hover); transform: translateY(-4px); }
.step-number {
    font-size: 2.5rem; font-weight: 900;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
}
.step-card h3 { font-size: 1rem; margin-bottom: 8px; }
.step-card p { color: var(--text-sec); font-size: 0.85rem; }
.step-card code {
    background: rgba(255,255,255,0.08);
    padding: 2px 6px; border-radius: 4px;
    font-size: 0.82rem;
}

.install-cta { text-align: center; }

/* ---- Shortcuts ---- */
.shortcuts { padding: 100px 0; }

.shortcut-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px; max-width: 800px; margin: 0 auto;
}

.shortcut-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    text-align: center;
    transition: all 0.3s;
}
.shortcut-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
}

.shortcut-keys {
    margin-bottom: 16px;
    font-size: 0.95rem; font-weight: 600;
    display: flex; align-items: center; justify-content: center; gap: 6px;
}

kbd {
    background: rgba(255,255,255,0.1);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 4px 10px;
    font-family: 'Inter', monospace;
    font-size: 0.8rem; font-weight: 700;
    color: var(--text);
}

.shortcut-card p {
    color: var(--text-sec); font-size: 0.88rem;
}

/* ---- FAQ ---- */
.faq { padding: 100px 0; }
.faq-list { max-width: 700px; margin: 0 auto; }

.faq-item {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 12px;
    overflow: hidden;
    transition: border-color 0.3s;
}
.faq-item:hover { border-color: var(--border-hover); }

.faq-question {
    width: 100%; padding: 20px 24px;
    background: var(--bg-card);
    border: none; color: var(--text);
    font-size: 0.95rem; font-weight: 600;
    text-align: left; cursor: pointer;
    display: flex; justify-content: space-between; align-items: center;
    font-family: inherit;
    transition: background 0.2s;
}
.faq-question:hover { background: var(--bg-card-hover); }
.faq-question i { transition: transform 0.3s; color: var(--text-sec); font-size: 0.8rem; }
.faq-item.open .faq-question i { transform: rotate(180deg); }

.faq-answer {
    max-height: 0; overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
}
.faq-item.open .faq-answer {
    max-height: 400px; padding: 0 24px 20px;
}
.faq-answer p { color: var(--text-sec); font-size: 0.9rem; line-height: 1.7; }
.faq-answer code {
    background: rgba(255,255,255,0.08);
    padding: 2px 8px; border-radius: 4px;
    font-size: 0.85rem;
}
.faq-answer a { color: var(--primary); text-decoration: none; }
.faq-answer a:hover { text-decoration: underline; }

/* ---- Footer ---- */
footer {
    padding: 60px 0 0;
    border-top: 1px solid var(--border);
}
.footer-grid {
    display: grid; grid-template-columns: 1.5fr 1fr;
    gap: 60px; padding-bottom: 40px;
}
.footer-logo {
    display: flex; align-items: center; gap: 10px;
    font-size: 1.2rem; font-weight: 800;
    margin-bottom: 12px;
}
.footer-logo img { border-radius: 8px; }
.footer-brand p { color: var(--text-sec); font-size: 0.9rem; max-width: 300px; }
.footer-links h4 { margin-bottom: 16px; font-size: 0.9rem; }
.footer-links a {
    display: flex; align-items: center; gap: 8px;
    color: var(--text-sec); text-decoration: none;
    font-size: 0.88rem; padding: 6px 0;
    transition: color 0.2s;
}
.footer-links a:hover { color: var(--text); }

.footer-bottom {
    border-top: 1px solid var(--border);
    padding: 24px 0; text-align: center;
}
.footer-bottom p { color: var(--text-sec); font-size: 0.8rem; }
.footer-bottom a { color: var(--primary); text-decoration: none; }

/* ---- Responsive ---- */
@media (max-width: 900px) {
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
    .steps-grid { grid-template-columns: repeat(2, 1fr); }
    .shortcut-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-grid { grid-template-columns: 1fr; text-align: center; }
    .hero-desc { margin: 0 auto 32px; }
    .hero-stats { justify-content: center; }
    .cta-group { justify-content: center; }
    .hero-content h1 { font-size: 2.6rem; }
    .hero-visual { max-width: 380px; margin: 0 auto; }
    .footer-grid { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 600px) {
    .nav-links { display: none; position: absolute; top: 100%; left: 0; right: 0; background: rgba(5,5,16,0.98); flex-direction: column; padding: 20px 24px; gap: 16px; border-bottom: 1px solid var(--border); }
    .nav-links.show { display: flex; }
    .hamburger { display: flex; }
    .hero-content h1 { font-size: 2rem; }
    .feature-grid { grid-template-columns: 1fr; }
    .steps-grid { grid-template-columns: 1fr; }
    .shortcut-grid { grid-template-columns: 1fr; }
    .section-header h2 { font-size: 1.8rem; }
    .hero-stats { flex-wrap: wrap; gap: 16px; }
}