/* ============================================
   BotDev Studio - Main Stylesheet
   Dark Theme + Glassmorphism + 3D Effects
   ============================================ */

/* === RESET & VARIABLES === */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: rgba(255,255,255,0.03);
    --bg-glass: rgba(255,255,255,0.05);
    --border-glass: rgba(255,255,255,0.06);
    --border-hover: rgba(139,92,246,0.3);
    --text-primary: #f0f0f5;
    --text-secondary: #8b8ba3;
    --text-muted: #555570;
    --purple: #8b5cf6;
    --blue: #06b6d4;
    --pink: #ec4899;
    --green: #22c55e;
    --orange: #f59e0b;
    --red: #ef4444;
    --gradient: linear-gradient(135deg, #8b5cf6, #06b6d4, #ec4899);
    --gradient-subtle: linear-gradient(135deg, rgba(139,92,246,0.15), rgba(6,182,212,0.15), rgba(236,72,153,0.15));
    --shadow-glow: 0 0 30px rgba(139,92,246,0.3);
    --shadow-card: 0 8px 32px rgba(0,0,0,0.3);
    --radius: 16px;
    --radius-sm: 10px;
    --transition: all 0.3s cubic-bezier(0.4,0,0.2,1);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

::selection { background: rgba(139,92,246,0.3); color: #fff; }

/* === CANVAS === */
#particle-canvas { position: fixed; top: 0; left: 0; width: 100%; height: 100%; z-index: 0; pointer-events: none; }

/* === CONTAINER === */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; position: relative; z-index: 1; }

/* === TYPOGRAPHY === */
h1,h2,h3,h4,h5,h6 { line-height: 1.2; font-weight: 700; }
.gradient-text { background: var(--gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }

/* === NAVBAR === */
.navbar {
    position: fixed; top: 0; width: 100%; z-index: 1000;
    padding: 20px 0; transition: var(--transition);
}
.navbar.scrolled {
    background: rgba(10,10,15,0.92); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-glass); padding: 12px 0;
}
.navbar .container { display: flex; justify-content: space-between; align-items: center; }

.logo { font-size: 1.5rem; font-weight: 800; text-decoration: none; color: var(--text-primary); letter-spacing: -0.5px; }
.logo span { background: var(--gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }

/* Nav Menu */
.nav-menu { display: flex; gap: 32px; list-style: none; align-items: center; }
.nav-menu a {
    color: var(--text-secondary); text-decoration: none; font-size: 0.9rem; font-weight: 500;
    transition: var(--transition); position: relative; padding: 4px 0;
}
.nav-menu a:hover { color: var(--text-primary); }
.nav-menu a::after {
    content: ''; position: absolute; bottom: -2px; left: 0; width: 0; height: 2px;
    background: var(--gradient); transition: width 0.3s;
}
.nav-menu a:hover::after { width: 100%; }

/* Burger Button */
.burger {
    display: none; flex-direction: column; gap: 5px; cursor: pointer;
    background: none; border: none; padding: 8px; z-index: 1001;
}
.burger span {
    display: block; width: 24px; height: 2px; background: var(--text-primary);
    border-radius: 2px; transition: var(--transition);
}
.burger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.burger.active span:nth-child(2) { opacity: 0; }
.burger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* === BUTTONS === */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 12px 28px; border-radius: var(--radius-sm); font-size: 0.95rem; font-weight: 600;
    text-decoration: none; border: none; cursor: pointer; transition: var(--transition);
    font-family: inherit; position: relative; overflow: hidden;
}
.btn-primary { background: var(--gradient); color: #fff; box-shadow: var(--shadow-glow); }
.btn-primary:hover { transform: translateY(-3px) scale(1.02); box-shadow: 0 10px 40px rgba(139,92,246,0.5); }
.btn-primary::before {
    content: ''; position: absolute; top: 0; left: -100%; width: 100%; height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent); transition: left 0.5s;
}
.btn-primary:hover::before { left: 100%; }
.btn-outline { background: transparent; color: var(--text-primary); border: 1px solid var(--border-glass); backdrop-filter: blur(10px); }
.btn-outline:hover { border-color: var(--border-hover); background: rgba(139,92,246,0.1); transform: translateY(-2px); }
.btn-ghost { background: var(--bg-glass); color: var(--text-primary); border: 1px solid var(--border-glass); }
.btn-ghost:hover { background: rgba(255,255,255,0.08); border-color: var(--border-hover); }
.btn-sm { padding: 8px 18px; font-size: 0.85rem; }
.btn-lg { padding: 16px 36px; font-size: 1.05rem; }
.btn-block { width: 100%; }

/* === HERO === */
.hero { min-height: 100vh; display: flex; align-items: center; justify-content: center; text-align: center; padding: 120px 24px 80px; }
.hero-content { max-width: 800px; }
.hero-badge {
    display: inline-flex; align-items: center; gap: 8px; padding: 8px 20px;
    background: var(--bg-glass); border: 1px solid var(--border-glass); border-radius: 50px;
    font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 32px; backdrop-filter: blur(10px);
}
.hero-badge .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--green); animation: pulse 2s infinite; }
@keyframes pulse { 0%,100%{opacity:1;transform:scale(1)} 50%{opacity:.5;transform:scale(.8)} }

.hero h1 { font-size: clamp(2.8rem,7vw,5rem); font-weight: 900; line-height: 1.05; margin-bottom: 24px; letter-spacing: -2px; }
.hero-desc { font-size: 1.15rem; color: var(--text-secondary); max-width: 600px; margin: 0 auto 12px; }
.hero-price { font-size: 1rem; color: var(--text-muted); margin-bottom: 36px; }
.hero-price strong { color: var(--orange); }
.typing-wrapper { display: inline; }
.typing-text { color: var(--purple); font-weight: 600; }
.typing-cursor {
    display: inline-block; width: 3px; height: 1.1em; background: var(--purple);
    margin-left: 4px; vertical-align: text-bottom; animation: blink 1s step-end infinite;
}
@keyframes blink { 50%{opacity:0} }

.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-stats { display: flex; gap: 48px; justify-content: center; margin-top: 60px; flex-wrap: wrap; }
.hero-stat { text-align: center; }
.hero-stat .number { font-size: 2rem; font-weight: 800; background: var(--gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.hero-stat .label { font-size: 0.8rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; }

/* === SECTION === */
.section { padding: 100px 0; position: relative; z-index: 1; }
.section-header { text-align: center; margin-bottom: 60px; }
.section-header h2 { font-size: 2.5rem; font-weight: 800; margin-bottom: 16px; letter-spacing: -1px; }
.section-header p { color: var(--text-secondary); max-width: 500px; margin: 0 auto; font-size: 1.05rem; }

/* === SERVICES === */
.services-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 24px; }
.service-card {
    background: var(--bg-glass); border: 1px solid var(--border-glass); border-radius: var(--radius);
    padding: 36px 28px; text-align: center; transition: var(--transition); position: relative; overflow: hidden;
    perspective: 1000px; transform-style: preserve-3d;
}
.service-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px; background: var(--gradient); transform: scaleX(0); transition: transform 0.4s; }
.service-card:hover::before { transform: scaleX(1); }
.service-card:hover { transform: translateY(-8px) rotateX(5deg); border-color: var(--border-hover); box-shadow: var(--shadow-card); }

.service-icon {
    width: 72px; height: 72px; border-radius: 18px; display: flex; align-items: center; justify-content: center;
    font-size: 1.8rem; margin: 0 auto 20px; background: var(--gradient-subtle); border: 1px solid var(--border-glass);
    transition: var(--transition);
}
.service-card:hover .service-icon { transform: scale(1.1) rotateZ(5deg); box-shadow: var(--shadow-glow); }
.service-card h3 { font-size: 1.15rem; font-weight: 700; margin-bottom: 8px; }
.service-card p { color: var(--text-secondary); font-size: 0.9rem; margin-bottom: 12px; }
.service-price { color: var(--orange); font-weight: 700; font-size: 0.95rem; }

/* === PRICING === */
.pricing-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 24px; align-items: stretch; }
.price-card {
    background: var(--bg-glass); border: 1px solid var(--border-glass); border-radius: var(--radius);
    padding: 40px 32px; text-align: center; transition: var(--transition); position: relative; overflow: hidden;
}
.price-card.popular { border-color: var(--purple); background: rgba(139,92,246,0.05); }
.price-card.popular::before {
    content: 'Phổ biến nhất'; position: absolute; top: 16px; right: -30px;
    background: var(--gradient); color: #fff; padding: 4px 40px; font-size: 0.7rem; font-weight: 600; transform: rotate(45deg);
}
.price-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-card); }
.price-card .icon { font-size: 2.5rem; margin-bottom: 16px; }
.price-card h3 { font-size: 1.3rem; font-weight: 700; margin-bottom: 8px; }
.price-card .price { font-size: 2.5rem; font-weight: 900; background: var(--gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; margin-bottom: 8px; }
.price-card .price-note { color: var(--text-muted); font-size: 0.85rem; margin-bottom: 24px; }
.price-card ul { list-style: none; text-align: left; margin-bottom: 28px; }
.price-card ul li { padding: 10px 0; border-bottom: 1px solid var(--border-glass); color: var(--text-secondary); font-size: 0.9rem; display: flex; align-items: center; gap: 10px; }
.price-card ul li i { color: var(--green); font-size: 0.8rem; }

/* === PROJECTS === */
.projects-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 24px; }
.project-card {
    background: var(--bg-glass); border: 1px solid var(--border-glass); border-radius: var(--radius);
    overflow: hidden; transition: var(--transition); perspective: 1000px;
}
.project-card:hover { transform: translateY(-6px) rotateY(3deg); border-color: var(--border-hover); box-shadow: var(--shadow-card); }
.project-thumb { height: 200px; display: flex; align-items: center; justify-content: center; font-size: 4rem; position: relative; overflow: hidden; }
.project-thumb::after { content: ''; position: absolute; inset: 0; background: linear-gradient(180deg,transparent 50%,var(--bg-glass)); }
.project-body { padding: 24px; }
.project-body h3 { font-size: 1.15rem; font-weight: 700; margin-bottom: 8px; }
.project-body p { color: var(--text-secondary); font-size: 0.9rem; margin-bottom: 16px; }
.tags { display: flex; gap: 8px; flex-wrap: wrap; }
.tags span { padding: 4px 12px; background: rgba(139,92,246,0.1); border: 1px solid rgba(139,92,246,0.2); border-radius: 20px; font-size: 0.75rem; color: var(--purple); font-weight: 500; }

/* === PROCESS === */
.process-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
.process-step { text-align: center; position: relative; padding: 32px 20px; }
.process-step::after { content: ''; position: absolute; top: 50px; right: -20px; width: 40px; height: 2px; background: var(--gradient); opacity: 0.3; }
.process-step:last-child::after { display: none; }
.step-number {
    width: 60px; height: 60px; border-radius: 50%; display: flex; align-items: center; justify-content: center;
    font-size: 1.3rem; font-weight: 800; margin: 0 auto 16px; background: var(--gradient-subtle);
    border: 2px solid var(--border-glass); color: var(--purple);
}
.process-step h4 { font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
.process-step p { color: var(--text-secondary); font-size: 0.85rem; }

/* === CONTACT === */
.contact-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: start; }
.contact-form { background: var(--bg-glass); border: 1px solid var(--border-glass); border-radius: var(--radius); padding: 36px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 0.8rem; font-weight: 600; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 6px; }
.form-group input, .form-group select, .form-group textarea {
    width: 100%; padding: 12px 16px; background: rgba(255,255,255,0.04); border: 1px solid var(--border-glass);
    border-radius: var(--radius-sm); color: var(--text-primary); font-family: inherit; font-size: 0.95rem;
    transition: var(--transition); outline: none;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus { border-color: var(--purple); box-shadow: 0 0 0 3px rgba(139,92,246,0.1); }
.form-group select {
    appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%238b8ba3' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat; background-position: right 14px center; padding-right: 36px; cursor: pointer;
}
.form-group select option { background: var(--bg-secondary); color: var(--text-primary); }
.form-group textarea { resize: vertical; min-height: 120px; }
.form-group .error { color: var(--red); font-size: 0.8rem; margin-top: 4px; display: none; }
.form-group.error input, .form-group.error textarea { border-color: var(--red); }

/* === SOCIAL LINKS === */
.social-links { display: flex; flex-direction: column; gap: 12px; }
.social-link {
    display: flex; align-items: center; gap: 16px; padding: 18px 24px; background: var(--bg-glass);
    border: 1px solid var(--border-glass); border-radius: var(--radius-sm); text-decoration: none;
    color: var(--text-primary); transition: var(--transition);
}
.social-link:hover { border-color: var(--border-hover); transform: translateX(8px); box-shadow: var(--shadow-card); }
.social-link .icon {
    width: 48px; height: 48px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
    font-size: 1.3rem; background: var(--gradient-subtle); border: 1px solid var(--border-glass); flex-shrink: 0;
}
.social-link .icon.zalo-icon { display: flex; align-items: center; justify-content: center; }
.social-link .icon.zalo-icon svg { width: 24px; height: 24px; }
.social-link .info { flex: 1; }
.social-link .info .name { font-weight: 600; font-size: 1rem; display: block; }
.social-link .info .handle { font-size: 0.85rem; color: var(--text-secondary); }

/* === MODAL === */
.modal-overlay { display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.75); backdrop-filter: blur(8px); z-index: 2000; align-items: center; justify-content: center; padding: 24px; }
.modal-overlay.active { display: flex; }
.modal {
    background: var(--bg-secondary); border: 1px solid var(--border-glass); border-radius: var(--radius);
    padding: 40px; max-width: 520px; width: 100%; max-height: 90vh; overflow-y: auto;
    position: relative; animation: modalIn 0.35s ease;
}
@keyframes modalIn { from{opacity:0;transform:scale(0.9) translateY(20px)} to{opacity:1;transform:scale(1) translateY(0)} }
.modal-close {
    position: absolute; top: 16px; right: 16px; width: 36px; height: 36px; border-radius: 8px;
    border: 1px solid var(--border-glass); background: rgba(255,255,255,0.05); color: var(--text-secondary);
    font-size: 1.3rem; cursor: pointer; display: flex; align-items: center; justify-content: center; transition: var(--transition);
}
.modal-close:hover { background: rgba(255,255,255,0.1); color: var(--text-primary); }
.modal h2 { font-size: 1.5rem; margin-bottom: 24px; font-weight: 800; }

/* === FOOTER === */
.footer { border-top: 1px solid var(--border-glass); padding: 60px 0 0; position: relative; z-index: 1; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 48px; margin-bottom: 40px; }
.footer-brand p { color: var(--text-secondary); font-size: 0.9rem; margin-top: 12px; max-width: 300px; line-height: 1.7; }

/* Footer Social */
.footer-social { display: flex; gap: 10px; margin-top: 20px; }
.footer-social a {
    width: 42px; height: 42px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
    background: var(--bg-glass); border: 1px solid var(--border-glass); color: var(--text-secondary);
    text-decoration: none; transition: var(--transition); font-size: 1rem;
}
.footer-social a:hover { background: var(--purple); color: #fff; border-color: var(--purple); transform: translateY(-3px); }
.footer-social a.zalo-icon { display: flex; align-items: center; justify-content: center; }
.footer-social a.zalo-icon svg { width: 18px; height: 18px; }

/* Footer Links */
.footer-links h4 { font-size: 0.85rem; text-transform: uppercase; letter-spacing: 1px; color: var(--text-primary); margin-bottom: 18px; font-weight: 700; }
.footer-links a {
    display: flex; align-items: center; gap: 8px; color: var(--text-secondary); text-decoration: none;
    font-size: 0.88rem; padding: 6px 0; transition: var(--transition);
}
.footer-links a i { width: 16px; font-size: 0.8rem; opacity: 0.6; }
.footer-links a:hover { color: var(--text-primary); padding-left: 6px; }
.footer-links a:hover i { opacity: 1; color: var(--purple); }

/* Footer Bottom */
.footer-bottom { border-top: 1px solid var(--border-glass); padding: 20px 0; }
.footer-bottom-inner { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; }
.footer-bottom p { color: var(--text-muted); font-size: 0.8rem; }
.footer-bottom-links { display: flex; gap: 12px; align-items: center; }
.footer-bottom-links a { color: var(--text-muted); text-decoration: none; font-size: 0.8rem; transition: var(--transition); }
.footer-bottom-links a:hover { color: var(--text-primary); }
.footer-bottom-links span { color: var(--text-muted); opacity: 0.3; }

/* === TOAST === */
#toast-container { position: fixed; top: 24px; right: 24px; z-index: 3000; display: flex; flex-direction: column; gap: 8px; }
.toast {
    padding: 14px 20px; background: var(--bg-secondary); border: 1px solid var(--border-glass); border-radius: var(--radius-sm);
    backdrop-filter: blur(20px); font-size: 0.9rem; animation: toastIn 0.3s ease; max-width: 350px; display: flex; align-items: center; gap: 10px;
}
.toast.success { border-color: rgba(34,197,94,0.3); }
.toast.success i { color: var(--green); }
.toast.error { border-color: rgba(239,68,68,0.3); }
.toast.error i { color: var(--red); }
@keyframes toastIn { from{opacity:0;transform:translateX(20px)} to{opacity:1;transform:translateX(0)} }

/* === SCROLL ANIM === */
[data-anim] { opacity: 0; transform: translateY(30px); transition: opacity 0.6s ease, transform 0.6s ease; }
[data-anim].visible { opacity: 1; transform: translateY(0); }
[data-anim="fade-up"] { transform: translateY(40px); }
[data-anim="fade-left"] { transform: translateX(-40px); }
[data-anim="fade-right"] { transform: translateX(40px); }

/* === LOADING === */
.loading-overlay { display: none; position: absolute; inset: 0; background: rgba(10,10,15,0.85); backdrop-filter: blur(6px); border-radius: var(--radius); z-index: 10; align-items: center; justify-content: center; flex-direction: column; gap: 12px; }
.loading-overlay.active { display: flex; }
.spinner { width: 36px; height: 36px; border: 3px solid rgba(255,255,255,0.1); border-top-color: var(--purple); border-radius: 50%; animation: spin 0.8s linear infinite; }
@keyframes spin { to{transform:rotate(360deg)} }

/* === RESPONSIVE === */
@media (max-width: 1024px) {
    .services-grid, .pricing-grid { grid-template-columns: repeat(2,1fr); }
    .process-grid { grid-template-columns: repeat(2,1fr); }
    .process-step::after { display: none; }
}

@media (max-width: 768px) {
    .burger { display: flex; }
    .nav-menu { display: none; }
    .nav-menu.open {
        display: flex; flex-direction: column; position: absolute; top: 100%; left: 0; right: 0;
        background: rgba(10,10,15,0.97); backdrop-filter: blur(20px); padding: 20px 24px;
        border-bottom: 1px solid var(--border-glass); gap: 4px; z-index: 999;
    }
    .nav-menu.open a { padding: 12px 16px; border-radius: 8px; font-size: 1rem; }
    .nav-menu.open a:hover { background: rgba(139,92,246,0.1); }

    .hero h1 { font-size: 2.2rem; letter-spacing: -1px; }
    .hero-desc { font-size: 1rem; }
    .hero-stats { gap: 24px; }
    .services-grid, .pricing-grid, .projects-grid, .process-grid { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; gap: 32px; }
    .section { padding: 60px 0; }
    .section-header h2 { font-size: 1.8rem; }
    .process-step::after { display: none; }
}