/* OPPO-inspired Premium Tech Style */
:root {
    --oppo-green: #00925f;
    --tech-black: #000000;
    --tech-grey-dark: #1d1d1f;
    --tech-grey-light: #f5f5f7;
    --tech-grey-medium: #86868b;
    --white: #ffffff;
    --border-color: #d2d2d7;
    --transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--white);
    color: var(--tech-black);
    line-height: 1.5;
    overflow-x: hidden;
}

header {
    background-color: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    height: 64px;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    border-bottom: 1px solid rgba(0,0,0,0.05);
}

.nav-container {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 40px;
    height: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    text-decoration: none;
    color: var(--tech-black);
    font-size: 20px;
    font-weight: 700;
    display: flex;
    align-items: center;
}

.logo img {
    height: 24px;
    margin-right: 8px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 40px;
}

.nav-links a {
    text-decoration: none;
    color: var(--tech-black);
    font-size: 14px;
    font-weight: 500;
    opacity: 0.8;
    transition: var(--transition);
}

.nav-links a:hover, .nav-links a.active {
    opacity: 1;
    color: var(--oppo-green);
}

.hero {
    height: 100vh;
    background-color: var(--tech-black);
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 50% 50%, rgba(0, 146, 95, 0.15) 0%, rgba(0,0,0,0) 70%);
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
    padding: 0 20px;
}

.hero h1 {
    font-size: 72px;
    font-weight: 700;
    letter-spacing: -2px;
    margin-bottom: 24px;
    line-height: 1.1;
}

.hero p {
    font-size: 24px;
    opacity: 0.7;
    margin-bottom: 48px;
}

.btn-premium {
    display: inline-block;
    background-color: var(--white);
    color: var(--tech-black);
    padding: 16px 48px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    transition: var(--transition);
}

.btn-premium:hover {
    transform: scale(1.05);
    background-color: var(--oppo-green);
    color: var(--white);
}

.section {
    padding: 120px 0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 40px;
}

.section-title {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 80px;
}

.grid-layout {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.feature-card {
    background-color: var(--tech-grey-light);
    border-radius: 32px;
    padding: 60px;
    text-align: center;
    transition: var(--transition);
    min-height: 500px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.feature-card:hover {
    background-color: #f0f0f2;
}

.feature-card.full-width {
    grid-column: span 2;
}

.feature-card .icon-box {
    margin-bottom: 40px;
}

.feature-card h3 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 20px;
}

.feature-card p {
    font-size: 18px;
    color: var(--tech-grey-medium);
}

.page-header {
    padding: 160px 0 80px;
    text-align: center;
    background-color: var(--tech-grey-light);
}

.content-body {
    padding: 100px 0;
}

.prose {
    max-width: 800px;
    margin: 0 auto;
    font-size: 20px;
}

.prose p { margin-bottom: 32px; }
.prose h2 { font-size: 36px; margin: 64px 0 24px; }

footer {
    background-color: var(--white);
    padding: 80px 0 40px;
    border-top: 1px solid var(--border-color);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 80px;
}

.footer-col h4 { font-size: 14px; font-weight: 600; margin-bottom: 24px; text-transform: uppercase; }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 12px; }
.footer-col a { text-decoration: none; color: var(--tech-grey-medium); font-size: 14px; transition: var(--transition); }
.footer-col a:hover { color: var(--oppo-green); }

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 40px;
    border-top: 1px solid var(--tech-grey-light);
    color: var(--tech-grey-medium);
    font-size: 12px;
}

@media (max-width: 1024px) {
    .hero h1 { font-size: 56px; }
    .grid-layout { grid-template-columns: 1fr; }
    .feature-card.full-width { grid-column: span 1; }
}

@media (max-width: 768px) {
    .nav-links { display: none; }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .hero h1 { font-size: 40px; }
    .section-title { font-size: 32px; }
}