:root {
    --bg-black: #000000;
    --card-gray: #121212;
    --accent-blue: #2997ff;
    --text-gray: #86868b;
    --white: #f5f5f7;
}

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

body {
    font-family: 'Inter', -apple-system, sans-serif;
    background-color: var(--bg-black);
    color: var(--white);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

/* NAVBAR */
nav {
    height: 44px;
    background: rgba(0,0,0,0.8);
    backdrop-filter: saturate(180%) blur(20px);
    position: fixed;
    top: 0; width: 100%; z-index: 1000;
    display: flex; justify-content: center; align-items: center;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}
nav a { color: var(--text-gray); text-decoration: none; font-size: 12px; margin: 0 20px; transition: 0.3s; }
nav a:hover { color: #fff; }

/* HERO */
header {
    padding-top: 120px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.app-icon {
    width: 120px;
    height: 120px;
    border-radius: 28px;
    margin-bottom: 30px;
    box-shadow: 0 0 50px rgba(41, 151, 255, 0.3);
}

header h1 {
    font-size: clamp(3rem, 10vw, 5rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    background: linear-gradient(180deg, #fff 0%, #a1a1a6 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

header h2 {
    font-size: 1.5rem;
    color: var(--text-gray);
    font-weight: 400;
    max-width: 640px;
    margin: 15px auto 40px;
    padding: 0 20px;
}

.cta-btn img {
    height: 50px;
    transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
.cta-btn:hover img { transform: scale(1.05); }

/* FEATURE SHOWCASE */
.showcase {
    margin-top: 80px;
    padding: 0 5%;
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.phone-frame {
    width: 260px;
    border-radius: 40px;
    border: 8px solid #1a1a1a;
    overflow: hidden;
    box-shadow: 0 50px 100px rgba(0,0,0,0.8);
    transition: transform 0.6s cubic-bezier(0.2, 1, 0.3, 1);
}
.phone-frame:hover { transform: translateY(-20px) scale(1.02); }
.phone-frame img { width: 100%; display: block; }

/* SECTIONS */
.page-section {
    max-width: 980px;
    margin: 120px auto 0;
    padding: 0 20px;
}

.page-section > h2 {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 12px;
}

.section-lead {
    color: var(--text-gray);
    text-align: center;
    max-width: 640px;
    margin: 0 auto 50px;
}

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

.feature-card {
    background: var(--card-gray);
    border: 1px solid #262626;
    border-radius: 16px;
    padding: 24px;
}
.feature-card h3 { font-size: 1rem; margin-bottom: 8px; }
.feature-card p { font-size: 0.85rem; color: var(--text-gray); }

/* GUIDE CARDS */
.guide-list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.guide-card {
    background: var(--card-gray);
    border: 1px solid #262626;
    border-radius: 16px;
    padding: 24px;
    text-decoration: none;
    color: var(--white);
    display: block;
    transition: 0.3s;
}
.guide-card:hover { border-color: var(--accent-blue); }
.guide-card h3 { font-size: 1rem; margin-bottom: 8px; }
.guide-card p { font-size: 0.85rem; color: var(--text-gray); }
.guide-card span { display: inline-block; margin-top: 14px; font-size: 0.85rem; color: var(--accent-blue); }

/* FAQ */
.faq-list { max-width: 720px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid #262626; padding: 24px 0; }
.faq-item h3 { font-size: 1.05rem; margin-bottom: 10px; }
.faq-item p { color: var(--text-gray); font-size: 0.95rem; }

/* GUIDE ARTICLE PAGES */
article.guide {
    max-width: 720px;
    margin: 110px auto 0;
    padding: 0 20px;
}

article.guide .back-link {
    color: var(--accent-blue);
    text-decoration: none;
    font-size: 0.85rem;
}

article.guide h1 {
    font-size: clamp(1.8rem, 5vw, 2.6rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin: 18px 0 20px;
}

article.guide .lead {
    font-size: 1.15rem;
    color: var(--white);
    margin-bottom: 36px;
}

article.guide h2 {
    font-size: 1.4rem;
    margin: 44px 0 16px;
}

article.guide p, article.guide li {
    color: var(--text-gray);
    font-size: 1rem;
    margin-bottom: 14px;
}

article.guide li strong, article.guide p strong { color: var(--white); }

article.guide ol, article.guide ul { padding-left: 24px; }
article.guide ol li { margin-bottom: 18px; }

article.guide .cta-box {
    background: var(--card-gray);
    border: 1px solid #262626;
    border-radius: 16px;
    padding: 30px;
    text-align: center;
    margin: 48px 0;
}
article.guide .cta-box p { color: var(--white); font-weight: 600; margin-bottom: 18px; }

.related { margin-top: 40px; }
.related a { display: block; color: var(--accent-blue); text-decoration: none; margin-bottom: 10px; font-size: 0.95rem; }
.related a:hover { text-decoration: underline; }

/* FOOTER */
footer {
    margin-top: 150px;
    background: #161617;
    padding: 80px 10% 40px;
    color: var(--text-gray);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    max-width: 1200px;
    margin: 0 auto;
    text-align: left;
}

.footer-col h4 { color: #f5f5f7; font-size: 14px; margin-bottom: 20px; text-transform: uppercase; }
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul li a { color: var(--text-gray); text-decoration: none; font-size: 13px; transition: 0.3s; }
.footer-col ul li a:hover { color: var(--accent-blue); text-decoration: underline; }
.footer-col p { font-size: 13px; }

.footer-bottom {
    max-width: 1200px;
    margin: 60px auto 0;
    padding-top: 20px;
    border-top: 1px solid #333;
    font-size: 12px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.support-card {
    background: #232324;
    padding: 20px;
    border-radius: 12px;
    margin-top: 20px;
    display: block;
    text-decoration: none;
    color: #fff;
    font-weight: 600;
    border: 1px solid #333;
    transition: 0.3s;
}
.support-card:hover { border-color: var(--accent-blue); }

/* Responsive */
@media (max-width: 1024px) {
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .feature-grid, .guide-list { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    header h1 { font-size: 2.5rem; }
    .footer-grid { grid-template-columns: 1fr; }
    .footer-bottom { flex-direction: column; gap: 20px; text-align: center; }
    .feature-grid, .guide-list { grid-template-columns: 1fr; }
}