/* PosterWords Landing Page — SEO-optimized responsive styles */

:root {
    --color-bg: #fafaf9;
    --color-surface: #ffffff;
    --color-text: #1c1917;
    --color-text-secondary: #57534e;
    --color-accent: #dc2626;
    --color-accent-hover: #b91c1c;
    --color-border: #e7e5e4;
    --color-hero-bg: #fef2f2;
    --font-sans: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
    --font-serif: 'Noto Serif SC', Georgia, serif;
    --radius: 12px;
    --radius-lg: 20px;
    --shadow-sm: 0 1px 3px rgba(0,0,0,.06);
    --shadow-md: 0 4px 12px rgba(0,0,0,.08);
    --shadow-lg: 0 12px 40px rgba(0,0,0,.1);
    --max-width: 1120px;
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    color: var(--color-text);
    background: var(--color-bg);
    -webkit-font-smoothing: antialiased;
}

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

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color .2s;
}

a:hover {
    color: var(--color-accent-hover);
}

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

/* Navigation */
.nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(250, 250, 249, .92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--color-text);
    font-weight: 700;
    font-size: 18px;
}

.nav-logo {
    border-radius: 8px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 28px;
}

.nav-links a {
    color: var(--color-text-secondary);
    font-size: 15px;
    font-weight: 500;
    transition: color .2s;
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 10px;
    font-weight: 600;
    font-size: 15px;
    transition: all .2s;
    border: none;
    cursor: pointer;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 14px;
    border-radius: 8px;
    background: var(--color-text);
    color: white;
}

.btn-sm:hover {
    background: #292524;
    color: white;
}

.btn-primary {
    background: var(--color-text);
    color: white;
    font-size: 16px;
    padding: 14px 28px;
}

.btn-primary:hover {
    background: #292524;
    color: white;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-lg {
    padding: 16px 32px;
    font-size: 17px;
}

/* Hero */
.hero {
    background: var(--color-hero-bg);
    padding: 80px 0 60px;
    overflow: hidden;
}

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

.hero h1 {
    font-size: clamp(32px, 5vw, 52px);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.02em;
    color: var(--color-text);
    margin-bottom: 20px;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: 32px;
    max-width: 520px;
}

.hero-meta {
    margin-top: 12px;
    font-size: 13px;
    color: var(--color-text-secondary);
}

.hero-visual {
    display: flex;
    justify-content: center;
}

.hero-visual img {
    max-height: 580px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

/* Social Proof */
.social-proof {
    padding: 40px 0;
    border-bottom: 1px solid var(--color-border);
}

.proof-items {
    display: flex;
    justify-content: center;
    gap: 60px;
    flex-wrap: wrap;
}

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

.proof-number {
    display: block;
    font-size: 28px;
    font-weight: 800;
    color: var(--color-text);
}

.proof-label {
    font-size: 14px;
    color: var(--color-text-secondary);
}

/* Sections */
.section {
    padding: 80px 0;
}

.section-alt {
    background: var(--color-surface);
}

.section-title {
    font-size: clamp(26px, 4vw, 38px);
    font-weight: 800;
    text-align: center;
    margin-bottom: 12px;
    letter-spacing: -0.01em;
}

.section-subtitle {
    text-align: center;
    color: var(--color-text-secondary);
    font-size: 17px;
    margin-bottom: 48px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Steps */
.steps-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.step-card {
    background: var(--color-surface);
    border-radius: var(--radius);
    padding: 32px 28px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--color-hero-bg);
    color: var(--color-accent);
    font-weight: 800;
    font-size: 18px;
    border-radius: 50%;
    margin-bottom: 16px;
}

.step-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 10px;
}

.step-card p {
    color: var(--color-text-secondary);
    font-size: 15px;
    line-height: 1.6;
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--color-bg);
    border-radius: var(--radius);
    padding: 28px 24px;
    border: 1px solid var(--color-border);
    transition: transform .2s, box-shadow .2s;
}

.feature-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    font-size: 28px;
    margin-bottom: 14px;
}

.feature-card h3 {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 8px;
}

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

/* Screenshots Gallery */
.screenshots-scroll {
    display: flex;
    gap: 20px;
    overflow-x: auto;
    padding: 20px 0 32px;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
}

.screenshots-scroll img {
    flex-shrink: 0;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    scroll-snap-align: center;
}

.screenshots-scroll::-webkit-scrollbar {
    height: 6px;
}

.screenshots-scroll::-webkit-scrollbar-track {
    background: var(--color-border);
    border-radius: 3px;
}

.screenshots-scroll::-webkit-scrollbar-thumb {
    background: #a8a29e;
    border-radius: 3px;
}

/* iOS Features */
.ios-features {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 28px;
}

.ios-item {
    text-align: center;
    padding: 24px;
}

.ios-item h3 {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 8px;
}

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

/* Use Cases */
.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.use-case {
    background: var(--color-bg);
    border-radius: var(--radius);
    padding: 28px 24px;
    border: 1px solid var(--color-border);
}

.use-case h3 {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--color-accent);
}

.use-case p {
    color: var(--color-text-secondary);
    font-size: 14px;
    line-height: 1.7;
    font-style: italic;
}

/* FAQ */
.faq-list {
    max-width: 720px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--color-border);
    padding: 20px 0;
}

.faq-item summary {
    font-size: 17px;
    font-weight: 600;
    cursor: pointer;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.faq-item summary::after {
    content: '+';
    font-size: 22px;
    font-weight: 300;
    color: var(--color-text-secondary);
    transition: transform .2s;
}

.faq-item[open] summary::after {
    transform: rotate(45deg);
}

.faq-item p {
    margin-top: 12px;
    color: var(--color-text-secondary);
    font-size: 15px;
    line-height: 1.7;
    padding-right: 32px;
}

/* CTA Section */
.cta-section {
    background: var(--color-text);
    color: white;
    text-align: center;
    padding: 80px 0;
}

.cta-inner h2 {
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    margin-bottom: 12px;
    color: white;
}

.cta-inner p {
    color: rgba(255,255,255,.7);
    font-size: 17px;
    margin-bottom: 28px;
}

.cta-section .btn-primary {
    background: white;
    color: var(--color-text);
}

.cta-section .btn-primary:hover {
    background: #f5f5f4;
    color: var(--color-text);
}

.cta-meta {
    margin-top: 12px;
    font-size: 13px;
    color: rgba(255,255,255,.5) !important;
}

/* Footer */
.footer {
    padding: 40px 0;
    border-top: 1px solid var(--color-border);
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 16px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 15px;
}

.footer-links {
    display: flex;
    gap: 24px;
}

.footer-links a {
    color: var(--color-text-secondary);
    font-size: 14px;
}

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

.footer-copy {
    font-size: 13px;
    color: var(--color-text-secondary);
}

/* Responsive */
@media (max-width: 1024px) {
    .features-grid,
    .ios-features,
    .use-cases-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .hero-inner {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }

    .hero-subtitle {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-cta {
        display: flex;
        justify-content: center;
    }

    .hero-visual img {
        max-height: 400px;
    }

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

    .features-grid,
    .ios-features,
    .use-cases-grid {
        grid-template-columns: 1fr;
    }

    .nav-links a:not(.btn) {
        display: none;
    }

    .proof-items {
        gap: 32px;
    }

    .footer-inner {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 48px 0 40px;
    }

    .section {
        padding: 56px 0;
    }

    .hero h1 {
        font-size: 28px;
    }

    .btn-primary {
        width: 100%;
        justify-content: center;
    }
}

/* Print */
@media print {
    .nav, .cta-section {
        display: none;
    }
}