/* ========================================
   THẾ GIỚI LỌC NƯỚC - LANDING PAGE
   Premium Water Filter Landing Page
   ======================================== */

/* ===== GOOGLE FONTS ===== */
@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@400;500;600;700;800;900&family=Nunito:wght@400;500;600;700;800&display=swap');

/* ===== CSS VARIABLES ===== */
:root {
    --primary: #0066CC;
    --primary-dark: #004c99;
    --primary-light: #e6f0ff;
    --teal: #00A99D;
    --teal-dark: #008a80;
    --teal-light: #e0f7f5;
    --accent: #FF6B35;
    --accent-light: #fff0e9;
    --dark: #1a1a2e;
    --dark-secondary: #2d2d44;
    --text: #333;
    --text-secondary: #666;
    --text-light: #999;
    --bg: #f8fafc;
    --white: #ffffff;
    --border: #e2e8f0;
    --shadow: 0 4px 20px rgba(0,0,0,0.08);
    --shadow-lg: 0 10px 40px rgba(0,0,0,0.12);
    --shadow-xl: 0 20px 60px rgba(0,0,0,0.15);
    --radius: 16px;
    --radius-sm: 8px;
    --radius-lg: 24px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --gradient-primary: linear-gradient(135deg, #0066CC 0%, #00A99D 100%);
    --gradient-dark: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    --gradient-hero: linear-gradient(135deg, rgba(0,102,204,0.95) 0%, rgba(0,169,157,0.9) 50%, rgba(0,102,204,0.85) 100%);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Nunito', sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.7;
    opacity: 0;
    transition: opacity 0.6s ease;
    overflow-x: hidden;
}

body.loaded {
    opacity: 1;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    line-height: 1.3;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

img {
    max-width: 100%;
    height: auto;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== NAVBAR ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 15px 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 2px 20px rgba(0,0,0,0.08);
    padding: 10px 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav-logo img {
    height: 45px;
    width: auto;
}

.nav-logo-text {
    font-family: 'Montserrat', sans-serif;
    font-weight: 800;
    font-size: 1.1rem;
    color: var(--white);
    transition: var(--transition);
}

.navbar.scrolled .nav-logo-text {
    color: var(--primary);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
    align-items: center;
}

.nav-links a {
    font-weight: 600;
    font-size: 0.9rem;
    color: rgba(255,255,255,0.9);
    position: relative;
    padding: 5px 0;
}

.navbar.scrolled .nav-links a {
    color: var(--text);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--teal);
    transition: width 0.3s ease;
}

.nav-links a:hover::after {
    width: 100%;
}

.nav-cta {
    background: var(--white) !important;
    color: var(--primary) !important;
    padding: 10px 24px !important;
    border-radius: 50px;
    font-weight: 700 !important;
    font-size: 0.85rem !important;
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
}

.navbar.scrolled .nav-cta {
    background: var(--gradient-primary) !important;
    color: var(--white) !important;
}

.nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.2);
}

.nav-cta::after {
    display: none !important;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
    background: none;
    border: none;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background: var(--white);
    border-radius: 3px;
    transition: var(--transition);
}

.navbar.scrolled .mobile-menu-btn span {
    background: var(--text);
}

/* ===== HERO SECTION ===== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    overflow: hidden;
    padding: 120px 0 80px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-bg img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.hero-bg::after {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-hero);
}

.hero .container {
    position: relative;
    z-index: 2;
}

.hero-content {
    max-width: 700px;
    color: var(--white);
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255,255,255,0.15);
    backdrop-filter: blur(10px);
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 24px;
    border: 1px solid rgba(255,255,255,0.2);
}

.hero h1 {
    font-size: 3.2rem;
    font-weight: 900;
    line-height: 1.15;
    margin-bottom: 20px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.15);
}

.hero h1 span {
    background: linear-gradient(135deg, #FFD700, #FF6B35);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.2rem;
    line-height: 1.7;
    opacity: 0.95;
    margin-bottom: 30px;
    font-weight: 500;
}

.hero-benefits {
    list-style: none;
    margin-bottom: 36px;
}

.hero-benefits li {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 14px;
}

.hero-benefits li .icon {
    width: 28px;
    height: 28px;
    background: rgba(255,255,255,0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    flex-shrink: 0;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 16px 36px;
    border-radius: 50px;
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    font-size: 1rem;
    cursor: pointer;
    border: none;
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn-primary {
    background: linear-gradient(135deg, #FF6B35, #FF8C5A);
    color: var(--white);
    box-shadow: 0 8px 30px rgba(255, 107, 53, 0.4);
    animation: pulse-btn 2s infinite;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 40px rgba(255, 107, 53, 0.5);
}

.btn-secondary {
    background: rgba(255,255,255,0.15);
    color: var(--white);
    border: 2px solid rgba(255,255,255,0.4);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255,255,255,0.25);
    transform: translateY(-3px);
}

@keyframes pulse-btn {
    0% { box-shadow: 0 0 0 0 rgba(255, 107, 53, 0.4); }
    70% { box-shadow: 0 0 0 15px rgba(255, 107, 53, 0); }
    100% { box-shadow: 0 0 0 0 rgba(255, 107, 53, 0); }
}

/* Hero Stats */
.hero-stats {
    display: flex;
    gap: 40px;
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.2);
}

.hero-stat {
    text-align: center;
}

.hero-stat .stat-num {
    font-family: 'Montserrat', sans-serif;
    font-size: 2.2rem;
    font-weight: 900;
    color: var(--white);
}

.hero-stat .stat-label {
    font-size: 0.85rem;
    opacity: 0.8;
    margin-top: 4px;
}

/* ===== SECTION COMMON ===== */
section {
    padding: 100px 0;
    position: relative;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: var(--primary-light);
    color: var(--primary);
    padding: 6px 18px;
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 16px;
}

.section-title {
    font-size: 2.4rem;
    color: var(--dark);
    margin-bottom: 16px;
}

.section-title span {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-desc {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 650px;
    margin: 0 auto;
}

/* ===== PROBLEMS SECTION ===== */
.problems {
    background: var(--white);
}

.problems-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.problem-card {
    background: var(--bg);
    border-radius: var(--radius);
    padding: 32px;
    border: 1px solid var(--border);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.problem-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #ff4444, #ff8800);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.problem-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

.problem-card:hover::before {
    opacity: 1;
}

.problem-icon {
    width: 56px;
    height: 56px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.6rem;
    margin-bottom: 20px;
    background: #fff0e9;
}

.problem-card h3 {
    font-size: 1.15rem;
    color: var(--dark);
    margin-bottom: 10px;
}

.problem-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.7;
}

/* Story box */
.story-box {
    background: linear-gradient(135deg, #fff9f5 0%, #fff0e6 100%);
    border-radius: var(--radius);
    padding: 36px;
    margin-top: 40px;
    border-left: 4px solid var(--accent);
    position: relative;
}

.story-box::before {
    content: '"';
    font-size: 5rem;
    color: var(--accent);
    opacity: 0.2;
    position: absolute;
    top: -10px;
    left: 20px;
    font-family: Georgia, serif;
}

.story-box p {
    font-size: 1.05rem;
    color: var(--text);
    font-style: italic;
    position: relative;
    z-index: 1;
    line-height: 1.8;
}

.story-box .story-author {
    margin-top: 16px;
    font-style: normal;
    font-weight: 700;
    color: var(--accent);
}

/* ===== SOLUTIONS SECTION ===== */
.solutions {
    background: var(--bg);
    position: relative;
    overflow: hidden;
}

.solutions::before {
    content: '';
    position: absolute;
    width: 500px;
    height: 500px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(0,169,157,0.06) 0%, transparent 70%);
    top: -100px;
    right: -150px;
    pointer-events: none;
}

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

.solutions-text h3 {
    font-size: 1.6rem;
    color: var(--dark);
    margin-bottom: 16px;
}

.solutions-text > p {
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-size: 1.05rem;
}

.benefit-list {
    list-style: none;
}

.benefit-item {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
    padding: 16px;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.benefit-item:hover {
    background: var(--white);
    box-shadow: var(--shadow);
}

.benefit-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    flex-shrink: 0;
}

.benefit-icon.health { background: #e8f5e9; }
.benefit-icon.save { background: #e3f2fd; }
.benefit-icon.convenient { background: #fff3e0; }
.benefit-icon.safe { background: #fce4ec; }
.benefit-icon.eco { background: #e0f7fa; }

.benefit-info h4 {
    font-size: 1.05rem;
    color: var(--dark);
    margin-bottom: 4px;
}

.benefit-info p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.solutions-visual {
    position: relative;
}

.solutions-visual img {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
}

/* ===== WHY US SECTION ===== */
.why-us {
    background: var(--white);
}

.why-us-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
}

.why-card {
    text-align: center;
    padding: 40px 28px;
    border-radius: var(--radius);
    background: var(--bg);
    border: 1px solid var(--border);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.why-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.why-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

.why-card:hover::before {
    transform: scaleX(1);
}

.why-icon {
    width: 72px;
    height: 72px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    margin: 0 auto 20px;
    background: var(--primary-light);
}

.why-card h3 {
    font-size: 1.1rem;
    color: var(--dark);
    margin-bottom: 10px;
}

.why-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== COMPARISON SECTION ===== */
.comparison {
    background: linear-gradient(160deg, #f0f7ff 0%, #e8faf8 50%, #f0f7ff 100%);
}

.comparison-table {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    max-width: 900px;
    margin: 0 auto;
}

.comparison-col {
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.comparison-col.before {
    border: 2px solid #ff7043;
}

.comparison-col.after {
    border: 2px solid var(--teal);
}

.comparison-header {
    padding: 20px;
    text-align: center;
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--white);
}

.comparison-col.before .comparison-header {
    background: linear-gradient(135deg, #ff7043, #ff5252);
}

.comparison-col.after .comparison-header {
    background: var(--gradient-primary);
}

.comparison-list {
    list-style: none;
    padding: 24px;
    background: var(--white);
}

.comparison-list li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
    font-size: 0.95rem;
}

.comparison-list li:last-child {
    border-bottom: none;
}

.comparison-list li .ico {
    flex-shrink: 0;
    font-size: 1.1rem;
    margin-top: 2px;
}

/* ===== PRODUCTS SECTION ===== */
.products {
    background: var(--white);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 28px;
}

.product-card {
    border-radius: var(--radius);
    overflow: hidden;
    background: var(--white);
    border: 1px solid var(--border);
    transition: var(--transition);
    position: relative;
}

.product-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
}

.product-badge {
    position: absolute;
    top: 16px;
    left: 16px;
    z-index: 2;
    background: var(--accent);
    color: var(--white);
    padding: 4px 14px;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
}

.product-img {
    width: 100%;
    height: 240px;
    overflow: hidden;
    background: linear-gradient(135deg, #f0f7ff, #e8faf8);
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-img img {
    max-height: 200px;
    object-fit: contain;
    transition: transform 0.4s ease;
}

.product-card:hover .product-img img {
    transform: scale(1.05);
}

.product-info {
    padding: 24px;
}

.product-brand {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 6px;
}

.product-info h3 {
    font-size: 1.1rem;
    color: var(--dark);
    margin-bottom: 12px;
    line-height: 1.4;
}

.product-price {
    font-family: 'Montserrat', sans-serif;
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--accent);
    margin-bottom: 16px;
}

.product-specs {
    list-style: none;
    margin-bottom: 20px;
}

.product-specs li {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    padding: 4px 0;
}

.product-specs li .sp-icon {
    color: var(--teal);
}

.product-btn {
    display: block;
    width: 100%;
    text-align: center;
    padding: 14px;
    border-radius: var(--radius-sm);
    background: var(--gradient-primary);
    color: var(--white);
    font-weight: 700;
    font-size: 0.9rem;
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.product-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 102, 204, 0.3);
}

/* ===== PROCESS SECTION ===== */
.process {
    background: var(--bg);
}

.process-steps {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    position: relative;
}

.process-step {
    flex: 1;
    min-width: 200px;
    max-width: 220px;
    text-align: center;
    padding: 24px 16px;
    position: relative;
}

.step-number {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--gradient-primary);
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Montserrat', sans-serif;
    font-weight: 800;
    font-size: 1.3rem;
    margin: 0 auto 16px;
    box-shadow: 0 4px 15px rgba(0, 102, 204, 0.3);
}

.process-step h3 {
    font-size: 1rem;
    color: var(--dark);
    margin-bottom: 8px;
}

.process-step p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.process-step::after {
    content: '→';
    position: absolute;
    top: 42px;
    right: -18px;
    font-size: 1.2rem;
    color: var(--primary);
    font-weight: 700;
}

.process-step:last-child::after {
    display: none;
}

/* ===== FAQ SECTION ===== */
.faq {
    background: var(--white);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

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

.faq-item.active {
    border-color: var(--primary);
    box-shadow: 0 4px 15px rgba(0, 102, 204, 0.1);
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    cursor: pointer;
    background: var(--white);
    transition: var(--transition);
    border: none;
    width: 100%;
    text-align: left;
    font-family: 'Montserrat', sans-serif;
    font-weight: 600;
    font-size: 1rem;
    color: var(--dark);
}

.faq-question:hover {
    background: var(--primary-light);
}

.faq-item.active .faq-question {
    background: var(--primary-light);
    color: var(--primary);
}

.faq-arrow {
    font-size: 1.2rem;
    transition: transform 0.3s ease;
    flex-shrink: 0;
    margin-left: 16px;
}

.faq-item.active .faq-arrow {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.4s ease;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer-content {
    padding: 0 24px 20px;
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: 0.95rem;
}

/* ===== CONTACT FORM SECTION ===== */
.contact {
    background: linear-gradient(160deg, #f0f7ff 0%, #e8faf8 50%, #f0f7ff 100%);
    position: relative;
    overflow: hidden;
}

.contact::before {
    content: '';
    position: absolute;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(0,102,204,0.06) 0%, transparent 70%);
    top: -100px;
    right: -150px;
    pointer-events: none;
}

.contact-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: start;
}

.contact-info h3 {
    font-size: 1.6rem;
    color: var(--dark);
    margin-bottom: 12px;
}

.contact-info > p {
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-size: 1rem;
}

.contact-cards {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.contact-card {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 20px;
    background: var(--white);
    border-radius: var(--radius-sm);
    box-shadow: 0 2px 10px rgba(0,0,0,0.04);
    transition: var(--transition);
    border: 1px solid var(--border);
}

.contact-card:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow);
    border-color: var(--primary);
}

.contact-card-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    flex-shrink: 0;
}

.contact-card-icon.hotline { background: linear-gradient(135deg, #ff6b6b, #ee5a24); color: white; }
.contact-card-icon.zalo { background: linear-gradient(135deg, #0068ff, #0055cc); color: white; }
.contact-card-icon.time { background: linear-gradient(135deg, #f0932b, #e67e22); color: white; }
.contact-card-icon.address { background: linear-gradient(135deg, #00b894, #00a99d); color: white; }

.contact-card-text h4 {
    font-size: 0.95rem;
    color: var(--dark);
    margin-bottom: 2px;
}

.contact-card-text p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Form */
.contact-form-wrap {
    background: var(--white);
    border-radius: var(--radius);
    padding: 36px;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border);
}

.contact-form-wrap h3 {
    font-size: 1.4rem;
    color: var(--dark);
    margin-bottom: 6px;
}

.contact-form-wrap > p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 24px;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-weight: 700;
    font-size: 0.85rem;
    color: var(--dark);
    margin-bottom: 6px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-family: 'Nunito', sans-serif;
    font-size: 0.95rem;
    color: var(--text);
    transition: var(--transition);
    background: var(--bg);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
    background: var(--white);
}

.form-group textarea {
    resize: vertical;
    min-height: 80px;
}

.form-submit-btn {
    width: 100%;
    padding: 16px;
    border-radius: var(--radius-sm);
    background: var(--gradient-primary);
    color: var(--white);
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    font-size: 1rem;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(0, 102, 204, 0.3);
}

.form-submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.form-note {
    text-align: center;
    margin-top: 12px;
    font-size: 0.8rem;
    color: var(--text-light);
}

.form-success {
    display: none;
    text-align: center;
    padding: 40px 20px;
}

.form-success.show {
    display: block;
}

.form-success .success-icon {
    font-size: 4rem;
    margin-bottom: 16px;
}

.form-success h3 {
    font-size: 1.4rem;
    color: var(--teal);
    margin-bottom: 8px;
}

.form-success p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ===== FOOTER ===== */
.footer {
    background: var(--gradient-dark);
    color: rgba(255,255,255,0.7);
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand h3 {
    font-size: 1.4rem;
    color: var(--white);
    margin-bottom: 12px;
}

.footer-brand p {
    font-size: 0.9rem;
    line-height: 1.8;
    margin-bottom: 16px;
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    background: rgba(255,255,255,0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    transition: var(--transition);
}

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

.footer-links h4 {
    color: var(--white);
    font-size: 1rem;
    margin-bottom: 16px;
}

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

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    font-size: 0.9rem;
    opacity: 0.7;
}

.footer-links a:hover {
    opacity: 1;
    color: var(--teal);
}

.footer-bottom {
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 0.85rem;
}

/* ===== FLOATING BUTTONS ===== */
.float-buttons {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 999;
    display: flex;
    flex-direction: column;
    gap: 14px;
    transition: opacity 0.3s ease;
}

.float-btn {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 1.5rem;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
    transition: var(--transition);
    position: relative;
    text-decoration: none;
}

.float-btn:hover {
    transform: scale(1.1);
}

.float-btn.hotline {
    background: linear-gradient(135deg, #ff6b6b, #ee5a24);
    animation: float-pulse-red 2s infinite;
}

.float-btn.zalo {
    background: #0068FF;
    animation: float-pulse-blue 2s infinite;
}

.float-btn .float-label {
    position: absolute;
    right: 70px;
    white-space: nowrap;
    background: var(--white);
    padding: 8px 16px;
    border-radius: 30px;
    font-size: 0.8rem;
    font-weight: 700;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    opacity: 0;
    transform: translateX(10px);
    transition: var(--transition);
    pointer-events: none;
}

.float-btn.hotline .float-label { color: #ee5a24; }
.float-btn.zalo .float-label { color: #0068FF; }
.float-btn.droppii .float-label { color: #6c5ce7; }

/* Droppii Button Styles */
.btn-droppii {
    background: linear-gradient(135deg, #6c5ce7, #a855f7);
    color: var(--white);
    box-shadow: 0 8px 30px rgba(108, 92, 231, 0.4);
}

.btn-droppii:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 40px rgba(108, 92, 231, 0.5);
    filter: brightness(1.1);
}

.float-btn.droppii {
    background: linear-gradient(135deg, #6c5ce7, #a855f7);
    animation: float-pulse-purple 2s infinite;
}

@keyframes float-pulse-purple {
    0% { box-shadow: 0 0 0 0 rgba(108, 92, 231, 0.4); }
    70% { box-shadow: 0 0 0 15px rgba(108, 92, 231, 0); }
    100% { box-shadow: 0 0 0 0 rgba(108, 92, 231, 0); }
}

.float-btn:hover .float-label {
    opacity: 1;
    transform: translateX(0);
}

@keyframes float-pulse-red {
    0% { box-shadow: 0 0 0 0 rgba(238, 90, 36, 0.4); }
    70% { box-shadow: 0 0 0 15px rgba(238, 90, 36, 0); }
    100% { box-shadow: 0 0 0 0 rgba(238, 90, 36, 0); }
}

@keyframes float-pulse-blue {
    0% { box-shadow: 0 0 0 0 rgba(0, 104, 255, 0.4); }
    70% { box-shadow: 0 0 0 15px rgba(0, 104, 255, 0); }
    100% { box-shadow: 0 0 0 0 rgba(0, 104, 255, 0); }
}

/* ===== SCROLL REVEAL ===== */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

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

.reveal-left {
    opacity: 0;
    transform: translateX(-30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal-left.visible {
    opacity: 1;
    transform: translateX(0);
}

.reveal-right {
    opacity: 0;
    transform: translateX(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal-right.visible {
    opacity: 1;
    transform: translateX(0);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
    .hero h1 { font-size: 2.6rem; }
    .section-title { font-size: 2rem; }
    .solutions-content { grid-template-columns: 1fr; gap: 40px; }
    .contact-layout { grid-template-columns: 1fr; }
    .footer-content { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .nav-links { 
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 20px;
        gap: 15px;
        box-shadow: var(--shadow);
        border-radius: 0 0 var(--radius) var(--radius);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links a {
        color: var(--text) !important;
        padding: 10px;
    }

    .nav-cta {
        background: var(--gradient-primary) !important;
        color: var(--white) !important;
        text-align: center;
    }

    .mobile-menu-btn { display: flex; }
    
    .hero { padding: 100px 0 60px; min-height: auto; }
    .hero h1 { font-size: 2rem; }
    .hero-subtitle { font-size: 1rem; }
    .hero-stats { gap: 24px; flex-wrap: wrap; }
    .hero-stat .stat-num { font-size: 1.6rem; }
    .hero-buttons { flex-direction: column; }
    .btn { padding: 14px 28px; font-size: 0.9rem; justify-content: center; }
    
    section { padding: 60px 0; }
    .section-title { font-size: 1.6rem; }
    .section-desc { font-size: 0.95rem; }
    
    .comparison-table { grid-template-columns: 1fr; }
    .products-grid { grid-template-columns: 1fr; }
    .process-steps { flex-direction: column; align-items: center; }
    .process-step::after { display: none; }
    .footer-content { grid-template-columns: 1fr; }
    
    .float-buttons { bottom: 20px; right: 20px; }
    .float-btn { width: 50px; height: 50px; font-size: 1.2rem; }
    .float-btn .float-label { display: none; }
    
    .contact-form-wrap { padding: 24px; }
}

@media (max-width: 480px) {
    .hero h1 { font-size: 1.7rem; }
    .container { padding: 0 16px; }
    .problems-grid { grid-template-columns: 1fr; }
    .why-us-grid { grid-template-columns: 1fr; }
}