/* ========================================
   CSS Variables & Reset
======================================== */
:root {
    --primary-color: #0071e3;
    --primary-dark: #0077ed;
    --secondary-color: #1d1d1f;
    --text-color: #1d1d1f;
    --text-light: #86868b;
    --background: #ffffff;
    --background-alt: #f5f5f7;
    --card-bg: #ffffff;
    --border-color: #d2d2d7;
    --gradient-1: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-2: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-3: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.15);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 30px;
    --transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

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

html {
    scroll-behavior: smooth;
}

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

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

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

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

/* ========================================
   Navigation
======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-sm);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 60px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1.5rem;
    font-weight: 700;
}

.logo-icon {
    font-size: 1.8rem;
}

.logo-text {
    background: linear-gradient(135deg, #1d1d1f 0%, #515154 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: 40px;
}

.nav-links a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-color);
    position: relative;
    padding: 5px 0;
    transition: var(--transition);
}

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

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

.nav-links a:hover {
    color: var(--primary-color);
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.hamburger span {
    width: 25px;
    height: 2px;
    background: var(--text-color);
    transition: var(--transition);
}

/* ========================================
   Hero Section
======================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 100px 5% 60px;
    background: linear-gradient(135deg, #f5f5f7 0%, #ffffff 50%, #f5f5f7 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 80%;
    height: 150%;
    background: radial-gradient(ellipse, rgba(0, 113, 227, 0.08) 0%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    flex: 1;
    max-width: 600px;
    z-index: 2;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 15px;
    color: var(--text-color);
}

.highlight {
    background: linear-gradient(135deg, #0071e3 0%, #40c9ff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1.2rem, 3vw, 1.8rem);
    color: var(--text-light);
    margin-bottom: 20px;
    font-weight: 500;
}

.hero-description {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 35px;
    max-width: 500px;
    line-height: 1.7;
}

.cta-button {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 32px;
    background: var(--primary-color);
    color: white;
    border-radius: var(--radius-xl);
    font-size: 1.1rem;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(0, 113, 227, 0.4);
}

.cta-button:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0, 113, 227, 0.5);
}

.cta-button svg {
    transition: transform 0.3s ease;
}

.cta-button:hover svg {
    transform: translateX(5px);
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1;
}

.floating-phone {
    animation: float 6s ease-in-out infinite;
}

.floating-phone img {
    max-width: 400px;
    filter: drop-shadow(0 30px 60px rgba(0, 0, 0, 0.2));
}

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(2deg); }
}

/* ========================================
   Section Styles
======================================== */
.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 700;
    text-align: center;
    margin-bottom: 15px;
    color: var(--text-color);
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-light);
    text-align: center;
    margin-bottom: 50px;
}

/* ========================================
   About Section
======================================== */
.about {
    padding: 100px 0;
    background: var(--background);
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.about-card {
    background: var(--background-alt);
    padding: 40px 30px;
    border-radius: var(--radius-lg);
    text-align: center;
    transition: var(--transition);
    border: 1px solid transparent;
}

.about-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.about-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.about-card h3 {
    font-size: 1.3rem;
    margin-bottom: 12px;
    color: var(--text-color);
}

.about-card p {
    color: var(--text-light);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* ========================================
   Phones Section
======================================== */
.phones {
    padding: 100px 0;
    background: var(--background-alt);
}

.filter-buttons {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 50px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 12px 28px;
    border: none;
    background: white;
    border-radius: var(--radius-xl);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
}

.filter-btn:hover {
    border-color: var(--primary-color);
}

.filter-btn.active {
    background: var(--primary-color);
    color: white;
}

.phone-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.phone-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: var(--transition);
    position: relative;
    border: 1px solid var(--border-color);
}

.phone-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.phone-card.hidden {
    display: none;
}

.phone-badge {
    position: absolute;
    top: 15px;
    left: 15px;
    padding: 6px 14px;
    background: var(--primary-color);
    color: white;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: var(--radius-xl);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    z-index: 10;
}

.phone-badge.new {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.phone-badge.value {
    background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
}

.phone-image {
    padding: 40px 30px 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(180deg, #f5f5f7 0%, #ffffff 100%);
    min-height: 280px;
}

.phone-image img {
    max-height: 220px;
    object-fit: contain;
    transition: transform 0.5s ease;
}

.phone-card:hover .phone-image img {
    transform: scale(1.08);
}

.phone-info {
    padding: 25px 30px 30px;
    text-align: center;
}

.phone-info h3 {
    font-size: 1.4rem;
    margin-bottom: 8px;
    color: var(--text-color);
}

.phone-tagline {
    font-size: 0.95rem;
    color: var(--text-light);
    margin-bottom: 15px;
}

.phone-specs {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 15px;
}

.phone-specs span {
    padding: 5px 12px;
    background: var(--background-alt);
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    color: var(--text-light);
}

.phone-price {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-color);
    margin-bottom: 20px;
}

.buy-button {
    display: inline-block;
    padding: 14px 40px;
    background: var(--primary-color);
    color: white;
    border-radius: var(--radius-xl);
    font-size: 1rem;
    font-weight: 600;
    transition: var(--transition);
    width: 100%;
}

.buy-button:hover {
    background: var(--primary-dark);
    transform: scale(1.02);
    box-shadow: 0 5px 20px rgba(0, 113, 227, 0.4);
}

/* ========================================
   Why Us Section
======================================== */
.why-us {
    padding: 100px 0;
    background: linear-gradient(135deg, #1d1d1f 0%, #2d2d30 100%);
    color: white;
}

.why-us .section-title {
    color: white;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

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

.stat-number {
    display: block;
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
    background: linear-gradient(135deg, #0071e3 0%, #40c9ff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 10px;
}

.stat-label {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.7);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* ========================================
   Contact Section
======================================== */
.contact {
    padding: 100px 0;
    background: var(--background);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-top: 50px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
}

.contact-icon {
    font-size: 2rem;
    width: 60px;
    height: 60px;
    background: var(--background-alt);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
}

.contact-item h4 {
    font-size: 1.1rem;
    margin-bottom: 5px;
    color: var(--text-color);
}

.contact-item p {
    color: var(--text-light);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.contact-form input,
.contact-form textarea {
    padding: 16px 20px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
    background: var(--background);
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.contact-form textarea {
    resize: vertical;
    min-height: 120px;
}

.submit-btn {
    padding: 16px 40px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--radius-xl);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.submit-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(0, 113, 227, 0.4);
}

/* ========================================
   Footer
======================================== */
.footer {
    background: var(--secondary-color);
    color: white;
    padding: 80px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 40px;
    margin-bottom: 50px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.footer-col p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.95rem;
    line-height: 1.7;
    margin-bottom: 20px;
}

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

.social-links a {
    font-size: 1.5rem;
    transition: var(--transition);
}

.social-links a:hover {
    transform: scale(1.2);
}

.footer-col h4 {
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: white;
}

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

.footer-col ul a {
    color: rgba(255, 255, 255, 0.6);
    transition: var(--transition);
    font-size: 0.95rem;
}

.footer-col ul a:hover {
    color: var(--primary-color);
    padding-left: 5px;
}

.newsletter-form {
    display: flex;
    gap: 10px;
    margin-top: 15px;
}

.newsletter-form input {
    flex: 1;
    padding: 12px 16px;
    border: none;
    border-radius: var(--radius-sm);
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 0.95rem;
}

.newsletter-form input::placeholder {
    color: rgba(255, 255, 255, 0.5);
}

.newsletter-form button {
    padding: 12px 20px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 1.2rem;
    transition: var(--transition);
}

.newsletter-form button:hover {
    background: var(--primary-dark);
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.9rem;
    margin-bottom: 5px;
}

.disclaimer {
    font-size: 0.8rem !important;
    color: rgba(255, 255, 255, 0.3) !important;
}

/* ========================================
   Back to Top Button
======================================== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
    box-shadow: var(--shadow-md);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-5px);
}

/* ========================================
   Animations
======================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fadeInUp {
    animation: fadeInUp 0.6s ease forwards;
}

/* ========================================
   Responsive Design
======================================== */
@media (max-width: 1024px) {
    .hero {
        flex-direction: column;
        text-align: center;
        padding-top: 120px;
    }

    .hero-content {
        max-width: 100%;
        margin-bottom: 50px;
    }

    .hero-description {
        margin: 0 auto 35px;
    }

    .floating-phone img {
        max-width: 300px;
    }

    .contact-grid {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 60px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        align-items: center;
        padding: 30px 0;
        gap: 25px;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
        box-shadow: var(--shadow-md);
    }

    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }

    .phone-grid {
        grid-template-columns: 1fr;
        max-width: 400px;
        margin: 0 auto;
    }

    .filter-buttons {
        gap: 10px;
    }

    .filter-btn {
        padding: 10px 20px;
        font-size: 0.85rem;
    }

    .stats-grid {
        grid-template-columns: 1fr 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .social-links {
        justify-content: center;
    }

    .newsletter-form {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .section-title {
        font-size: 1.8rem;
    }

    .about-card {
        padding: 30px 20px;
    }

    .phone-image {
        min-height: 220px;
        padding: 30px 20px 15px;
    }

    .phone-image img {
        max-height: 180px;
    }

    .phone-info {
        padding: 20px;
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }

    .back-to-top {
        width: 45px;
        height: 45px;
        bottom: 20px;
        right: 20px;
    }
}

/* ========================================
   Loading Animation for Images
======================================== */
.phone-image img {
    opacity: 0;
    transition: opacity 0.5s ease;
}

.phone-image img.loaded {
    opacity: 1;
}

/* Skeleton loading effect */
.phone-image::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.phone-image.loaded::before {
    display: none;
}

@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}