/* ── Reset & Base ── */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg: #0A0A0A;
    --bg-card: rgba(255, 255, 255, 0.05);
    --bg-card-hover: rgba(255, 255, 255, 0.08);
    --text: #FFFFFF;
    --text-secondary: rgba(255, 255, 255, 0.7);
    --text-muted: rgba(255, 255, 255, 0.4);
    --primary: #BBF907;
    --primary-dark: #9AD006;
    --max-width: 1200px;
    --nav-height: 64px;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Pretendard Variable', Pretendard, -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

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

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

/* ── Navigation ── */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    height: var(--nav-height);
    transition: background-color 0.3s, backdrop-filter 0.3s;
}

.navbar.scrolled {
    background-color: rgba(10, 10, 10, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 20px;
    font-weight: 700;
}

.logo img {
    height: 28px;
    width: auto;
}

.nav-cta {
    padding: 12px 24px;
    background-color: var(--primary);
    color: #000;
    font-size: 14px;
    font-weight: 600;
    border-radius: 24px;
    transition: background-color 0.2s, transform 0.2s;
    min-height: 44px;
    display: flex;
    align-items: center;
}

.nav-cta:hover {
    background-color: var(--primary-dark);
    transform: scale(1.02);
}

/* ── Hero ── */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: var(--nav-height);
    background: radial-gradient(ellipse at 30% 50%, rgba(187, 249, 7, 0.06) 0%, transparent 60%);
}

.hero-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 60px 24px;
    display: flex;
    align-items: center;
    gap: 60px;
    width: 100%;
}

.hero-content {
    flex: 1;
}

.hero-content h1 {
    font-size: 52px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 16px;
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: 20px;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 20px;
}

.hero-description {
    font-size: 17px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 36px;
}

.store-buttons {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.store-btn {
    display: inline-block;
    transition: transform 0.2s, opacity 0.2s;
}

.store-btn:hover {
    transform: translateY(-2px);
    opacity: 0.9;
}

.store-btn img {
    height: 40px;
}

.hero-mockup {
    flex: 0 0 380px;
}

/* ── Phone Mockup ── */
.phone-frame {
    width: 320px;
    height: 640px;
    background: linear-gradient(145deg, #1a1a1a, #2a2a2a);
    border-radius: 32px;
    padding: 8px;
    box-shadow: 0 40px 80px rgba(0, 0, 0, 0.5);
    margin: 0 auto;
    animation: float 4s ease-in-out infinite;
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: #0A0A0A;
    border-radius: 24px;
    overflow: hidden;
    position: relative;
}

/* ── Mockup Slideshow ── */
.mockup-slideshow {
    position: relative;
}

.mockup-slide {
    position: absolute;
    top: -30px;
    left: 0;
    width: 100%;
    height: calc(100% + 30px);
    object-fit: cover;
    opacity: 0;
    transition: opacity 0.8s ease-in-out;
    image-rendering: auto;
}

.mockup-slide.active {
    opacity: 1;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}

/* ── Features ── */
.features {
    padding: 100px 0;
    background: linear-gradient(180deg, transparent 0%, rgba(187, 249, 7, 0.02) 50%, transparent 100%);
}

.section-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 56px;
    letter-spacing: -0.5px;
}

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

.feature-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 16px;
    padding: 32px 24px;
    transition: background-color 0.3s, transform 0.3s, border-color 0.3s;
}

.feature-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-4px);
    border-color: rgba(187, 249, 7, 0.15);
}

.feature-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: rgba(187, 249, 7, 0.1);
    border-radius: 12px;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
}

.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ── Screenshots ── */
.screenshots {
    padding: 100px 0;
}

.screenshot-carousel {
    display: flex;
    gap: 16px;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    padding: 0 24px 20px;
    scrollbar-width: none;
    justify-content: center;
}

.screenshot-carousel::-webkit-scrollbar {
    display: none;
}

.screenshot-item {
    flex: 0 0 300px;
    scroll-snap-align: center;
    text-align: center;
}

.screenshot-frame {
    width: 280px;
    height: 560px;
    background: #0A0A0A;
    border-radius: 28px;
    overflow: hidden;
    margin: 0 auto 12px;
    border: 1px solid rgba(255, 255, 255, 0.06);
}

.screenshot-frame img {
    width: 100%;
    height: calc(100% + 30px);
    object-fit: cover;
    margin-top: -30px;
    image-rendering: auto;
}

.screenshot-item p {
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
}

/* ── CTA ── */
.cta {
    padding: 100px 0;
    text-align: center;
    background: radial-gradient(ellipse at 50% 50%, rgba(187, 249, 7, 0.06) 0%, transparent 60%);
}

.cta h2 {
    font-size: 40px;
    font-weight: 700;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.cta p {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 36px;
}

.cta .store-buttons {
    justify-content: center;
}

/* ── Footer ── */
.footer {
    padding: 40px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    text-align: center;
}

.footer-links {
    margin-bottom: 12px;
}

.footer-links a {
    color: var(--text-secondary);
    font-size: 13px;
    transition: color 0.2s;
}

.footer-links a:hover {
    color: var(--text);
}

.footer-links .divider {
    color: var(--text-muted);
    margin: 0 12px;
    font-size: 12px;
}

.footer-contact {
    margin-bottom: 12px;
}

.footer-contact a {
    color: var(--text-muted);
    font-size: 13px;
    transition: color 0.2s;
}

.footer-contact a:hover {
    color: var(--primary);
}

.footer-copyright {
    color: var(--text-muted);
    font-size: 12px;
}

/* ── Fade-in Animation ── */
.fade-in {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ── Responsive: Tablet ── */
@media (max-width: 1199px) {
    .hero-content h1 {
        font-size: 42px;
    }

    .feature-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .hero-mockup {
        flex: 0 0 320px;
    }

    .phone-frame {
        width: 260px;
        height: 520px;
    }
}

/* ── Responsive: Mobile ── */
@media (max-width: 767px) {
    .hero {
        min-height: 100svh;
        padding-top: calc(var(--nav-height) + 40px);
        padding-bottom: 40px;
    }

    .hero-inner {
        flex-direction: column;
        text-align: center;
        gap: 40px;
        padding: 40px 20px;
    }

    .hero-content h1 {
        font-size: 32px;
    }

    .hero-subtitle {
        font-size: 17px;
    }

    .hero-description {
        font-size: 15px;
    }

    .hero-description br {
        display: none;
    }

    .store-buttons {
        justify-content: center;
    }

    .store-btn img {
        height: 36px;
    }

    .hero-mockup {
        flex: none;
    }

    .phone-frame {
        width: min(78vw, 320px);
        height: auto;
        aspect-ratio: 1 / 2;
        border-radius: 30px;
    }

    .phone-screen {
        border-radius: 20px;
        font-size: 16px;
    }

    .section-title {
        font-size: 26px;
        margin-bottom: 36px;
    }

    .features {
        padding: 60px 0;
    }

    .feature-grid {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    .feature-card {
        padding: 24px 20px;
    }

    .screenshots {
        padding: 60px 0;
    }

    .screenshot-carousel {
        justify-content: flex-start;
        gap: 12px;
        padding: 0 20px 20px;
    }

    .screenshot-carousel::after {
        content: '';
        flex: 0 0 20px;
    }

    .screenshot-item {
        flex: 0 0 min(65vw, 270px);
    }

    .screenshot-frame {
        width: min(60vw, 250px);
        height: auto;
        aspect-ratio: 1 / 2;
        border-radius: 24px;
    }

    .screenshot-frame img {
        height: calc(100% + 16px);
        margin-top: -16px;
    }

    .cta {
        padding: 60px 0;
    }

    .cta h2 {
        font-size: 28px;
    }

    .cta p {
        font-size: 16px;
    }

    .footer-links a {
        font-size: 14px;
    }

    .footer-contact a {
        font-size: 14px;
    }

    .footer-copyright {
        font-size: 13px;
    }
}