/* === Design Tokens === */
:root {
    --color-bg: #0a0e17;
    --color-bg-alt: #111827;
    --color-bg-card: #1a2035;
    --color-accent: #30C2FF;
    --color-accent-hover: #5ad0ff;
    --color-accent-glow: rgba(48, 194, 255, 0.15);
    --color-text: #cbd5e1;
    --color-text-muted: #64748b;
    --color-text-heading: #f1f5f9;
    --color-border: #1e293b;
    --color-success: #10b981;
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --max-w: 1120px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --transition: 0.3s cubic-bezier(0.23, 1, 0.32, 1);
}

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

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

body {
    font-family: var(--font);
    font-size: 15px;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

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

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

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

ul {
    list-style: none;
}

h1, h2, h3, h4 {
    color: var(--color-text-heading);
    line-height: 1.2;
    font-weight: 700;
}

/* === Layout (mobile-first) === */
.container {
    width: 100%;
    max-width: var(--max-w);
    margin: 0 auto;
    padding: 0 16px;
}

section {
    padding: 48px 0;
    scroll-margin-top: 60px;
}

.section-subtitle {
    color: var(--color-text-muted);
    font-size: 0.95rem;
    max-width: 600px;
    margin: 0 auto 32px;
    text-align: center;
}

/* === Header === */
#header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 12px 0;
    background: rgba(10, 14, 23, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: background var(--transition), box-shadow var(--transition), padding var(--transition);
}

#header.scrolled {
    background: rgba(10, 14, 23, 0.95);
    box-shadow: 0 1px 0 var(--color-border);
    padding: 8px 0;
}

#header nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--color-text-heading);
    text-decoration: none;
    flex-shrink: 0;
}

.logo:hover {
    color: var(--color-text-heading);
}

.logo img {
    border-radius: 8px;
    width: 32px;
    height: 32px;
}

/* Nav toggle (hamburger) — visible by default, hidden on desktop */
.nav-toggle {
    display: flex;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 110;
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--color-text-heading);
    border-radius: 2px;
    transition: transform var(--transition), opacity var(--transition);
}

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

.nav-toggle.open span:nth-child(2) {
    opacity: 0;
}

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

/* Nav links — mobile drawer by default */
.nav-links {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: 260px;
    background: rgba(17, 24, 39, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    padding: 72px 24px 32px;
    gap: 0;
    transform: translateX(100%);
    transition: transform var(--transition);
    border-left: 1px solid var(--color-border);
    z-index: 105;
}

.nav-links.open {
    transform: translateX(0);
}

.nav-links li {
    width: 100%;
}

.nav-links a {
    display: block;
    color: var(--color-text);
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    padding: 10px 0;
    transition: color var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--color-accent);
}

.nav-cta {
    background: var(--color-accent);
    color: var(--color-bg) !important;
    padding: 10px 20px !important;
    border-radius: 100px;
    font-weight: 600;
    font-size: 0.9rem;
    text-align: center;
    margin-top: 8px;
    transition: background var(--transition), transform var(--transition);
}

.nav-cta:hover {
    background: var(--color-accent-hover);
    color: var(--color-bg) !important;
}

/* Mobile menu overlay */
.nav-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 99;
}

.nav-overlay.open {
    display: block;
}

/* === Buttons === */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 100px;
    font-family: var(--font);
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    border: none;
    transition: all var(--transition);
    -webkit-tap-highlight-color: transparent;
}

.btn-primary {
    background: var(--color-accent);
    color: var(--color-bg);
}

.btn-primary:hover {
    background: var(--color-accent-hover);
    color: var(--color-bg);
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(48, 194, 255, 0.3);
}

.btn-secondary {
    background: transparent;
    color: var(--color-accent);
    border: 1.5px solid var(--color-accent);
}

.btn-secondary:hover {
    background: var(--color-accent-glow);
    color: var(--color-accent-hover);
    transform: translateY(-2px);
}

/* === Hero (mobile-first) === */
#hero {
    padding: 100px 0 40px;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

#hero::before {
    content: '';
    position: absolute;
    top: -40%;
    right: -50%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(48, 194, 255, 0.08) 0%, transparent 70%);
    pointer-events: none;
}

.hero-grid {
    display: flex;
    flex-direction: column;
    gap: 32px;
    align-items: center;
    text-align: center;
}

.hero-badge img {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-md);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    margin: 0 auto;
}

#hero h1 {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-top: 12px;
    background: linear-gradient(135deg, var(--color-text-heading) 0%, var(--color-accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.05rem;
    color: var(--color-accent);
    font-weight: 500;
    margin-top: 4px;
}

.hero-tagline {
    font-size: 0.95rem;
    color: var(--color-text);
    margin-top: 12px;
    line-height: 1.6;
}

.rating {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    margin-top: 16px;
    flex-wrap: wrap;
}

.stars {
    color: #facc15;
    font-size: 1rem;
    letter-spacing: 2px;
}

.rating-score {
    font-weight: 600;
    color: var(--color-text-heading);
    font-size: 0.9rem;
}

.rating-count {
    color: var(--color-text-muted);
    font-size: 0.8rem;
}

.app-store-btn {
    margin-top: 20px;
}

.app-store-btn svg {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
}

.hero-free {
    margin-top: 10px;
    color: var(--color-text-muted);
    font-size: 0.8rem;
}

.hero-image {
    display: flex;
    justify-content: center;
    width: 100%;
}

.hero-image img {
    max-width: 280px;
    width: 100%;
    filter: drop-shadow(0 20px 60px rgba(48, 194, 255, 0.1));
}

/* === Features (mobile-first) === */
#features {
    background: var(--color-bg-alt);
}

#features h2,
#screenshots h2,
#pricing h2,
#faq h2,
#contact h2 {
    text-align: center;
    font-size: 1.5rem;
    margin-bottom: 8px;
}

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

.feature-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 20px 16px;
    transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.feature-card:hover {
    border-color: var(--color-accent);
    box-shadow: 0 4px 20px rgba(48, 194, 255, 0.06);
}

.feature-icon {
    color: var(--color-accent);
    margin-bottom: 10px;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
}

.feature-card h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 6px;
}

.feature-card p {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    line-height: 1.5;
}

/* === Screenshots (mobile-first) === */
.screenshots-gallery {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

.screenshots-gallery figure {
    width: calc(50% - 8px);
    max-width: 200px;
    text-align: center;
}

.screenshots-gallery img {
    border-radius: var(--radius-md);
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.4);
    transition: transform var(--transition);
}

.screenshots-gallery img:hover {
    transform: scale(1.02);
}

.screenshots-gallery figcaption {
    margin-top: 10px;
    color: var(--color-text-muted);
    font-size: 0.8rem;
}

/* === Pricing (mobile-first) === */
#pricing {
    background: var(--color-bg-alt);
}

.pricing-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    max-width: 400px;
    margin: 0 auto;
}

.pricing-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 28px 20px;
    text-align: center;
    position: relative;
    transition: transform var(--transition);
}

.pricing-card:hover {
    transform: translateY(-2px);
}

.pricing-card.featured {
    border-color: var(--color-accent);
    box-shadow: 0 0 30px rgba(48, 194, 255, 0.1);
}

.pricing-badge {
    position: absolute;
    top: -11px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--color-accent);
    color: var(--color-bg);
    font-size: 0.7rem;
    font-weight: 700;
    padding: 3px 14px;
    border-radius: 100px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    white-space: nowrap;
}

.pricing-card h3 {
    font-size: 1.2rem;
    margin-bottom: 12px;
}

.price {
    margin-bottom: 20px;
}

.price-amount {
    font-size: 2.2rem;
    font-weight: 800;
    color: var(--color-text-heading);
    letter-spacing: -0.02em;
}

.price-period {
    color: var(--color-text-muted);
    font-size: 0.9rem;
}

.pricing-card ul {
    text-align: left;
    margin-bottom: 24px;
}

.pricing-card li {
    padding: 6px 0;
    padding-left: 24px;
    position: relative;
    color: var(--color-text);
    font-size: 0.85rem;
}

.pricing-card li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 10px;
    width: 14px;
    height: 14px;
    background: url("data:image/svg+xml,%3Csvg width='14' height='14' viewBox='0 0 16 16' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M13.3 4.3a1 1 0 0 1 0 1.4l-6 6a1 1 0 0 1-1.4 0l-3-3a1 1 0 1 1 1.4-1.4L6.6 9.6l5.3-5.3a1 1 0 0 1 1.4 0z' fill='%2330C2FF'/%3E%3C/svg%3E") no-repeat;
    background-size: contain;
}

.pricing-card .btn {
    width: 100%;
}

/* === FAQ (mobile-first) === */
.faq-list {
    max-width: 720px;
    margin: 0 auto;
}

details {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    margin-bottom: 8px;
    background: var(--color-bg-card);
    transition: border-color var(--transition);
}

details:hover,
details[open] {
    border-color: var(--color-accent);
}

summary {
    padding: 14px 40px 14px 16px;
    font-weight: 600;
    color: var(--color-text-heading);
    cursor: pointer;
    position: relative;
    list-style: none;
    font-size: 0.9rem;
    line-height: 1.4;
}

summary::-webkit-details-marker {
    display: none;
}

summary::after {
    content: '+';
    position: absolute;
    right: 14px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.2rem;
    color: var(--color-accent);
    font-weight: 300;
}

details[open] summary::after {
    content: '\2212';
}

.faq-answer {
    padding: 0 16px 14px;
    color: var(--color-text);
    line-height: 1.6;
    font-size: 0.85rem;
}

/* === Contact (mobile-first) === */
#contact {
    background: var(--color-bg-alt);
}

.contact-form {
    max-width: 520px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-text-heading);
    margin-bottom: 4px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 10px 12px;
    font-family: var(--font);
    font-size: 16px; /* prevent iOS zoom */
    color: var(--color-text-heading);
    outline: none;
    transition: border-color var(--transition), box-shadow var(--transition);
    resize: vertical;
    -webkit-appearance: none;
    appearance: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-muted);
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px var(--color-accent-glow);
}

.form-group.error input,
.form-group.error textarea {
    border-color: #ef4444;
}

.form-error {
    display: none;
    font-size: 0.75rem;
    color: #ef4444;
    margin-top: 4px;
}

.form-group.error .form-error {
    display: block;
}

.contact-submit {
    width: 100%;
    margin-top: 8px;
}

.contact-submit:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
    box-shadow: none !important;
}

.form-status {
    text-align: center;
    margin-top: 12px;
    font-size: 0.9rem;
    min-height: 20px;
}

.form-status.success {
    color: var(--color-success);
}

.form-status.error {
    color: #ef4444;
}

/* === Footer (mobile-first) === */
footer {
    background: var(--color-bg-alt);
    border-top: 1px solid var(--color-border);
    padding: 40px 0 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    margin-bottom: 24px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--color-text-heading);
    margin-bottom: 8px;
}

.footer-logo img {
    border-radius: 6px;
    width: 28px;
    height: 28px;
}

.footer-brand p {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    margin-top: 2px;
}

.footer-links h4 {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-text-muted);
    margin-bottom: 10px;
    font-weight: 600;
}

.footer-links li {
    margin-bottom: 8px;
}

.footer-links a {
    color: var(--color-text);
    font-size: 0.85rem;
}

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

.footer-download {
    display: flex;
    align-items: flex-start;
}

.app-store-link {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 6px 12px;
    display: inline-flex;
    align-items: center;
    transition: border-color var(--transition);
}

.app-store-link:hover {
    border-color: var(--color-accent);
}

.app-store-link img {
    height: 32px;
    width: auto;
}

.footer-bottom {
    border-top: 1px solid var(--color-border);
    padding-top: 16px;
    text-align: center;
    color: var(--color-text-muted);
    font-size: 0.8rem;
}

/* === Animations on scroll === */
.fade-in {
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

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

/* =========================================
   TABLET (min-width: 640px)
   ========================================= */
@media (min-width: 640px) {
    body {
        font-size: 16px;
    }

    .container {
        padding: 0 24px;
    }

    section {
        padding: 64px 0;
        scroll-margin-top: 68px;
    }

    .section-subtitle {
        font-size: 1.05rem;
        margin-bottom: 40px;
    }

    #hero {
        padding: 120px 0 60px;
    }

    #hero h1 {
        font-size: 2.8rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .hero-tagline {
        font-size: 1rem;
    }

    .hero-badge img {
        width: 72px;
        height: 72px;
    }

    .hero-image img {
        max-width: 360px;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

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

    .screenshots-gallery {
        gap: 24px;
    }

    .screenshots-gallery figure {
        width: auto;
        max-width: 240px;
    }

    .pricing-grid {
        grid-template-columns: repeat(2, 1fr);
        max-width: 620px;
    }

    .pricing-card {
        padding: 32px 24px;
    }

    .price-amount {
        font-size: 2.5rem;
    }

    summary {
        padding: 16px 48px 16px 20px;
        font-size: 0.95rem;
    }

    summary::after {
        right: 18px;
    }

    .faq-answer {
        padding: 0 20px 16px;
        font-size: 0.9rem;
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
    }

    #features h2,
    #screenshots h2,
    #pricing h2,
    #faq h2,
    #contact h2 {
        font-size: 1.8rem;
        margin-bottom: 10px;
    }
}

/* =========================================
   DESKTOP (min-width: 1024px)
   ========================================= */
@media (min-width: 1024px) {
    .container {
        padding: 0 32px;
    }

    section {
        padding: 80px 0;
        scroll-margin-top: 72px;
    }

    .section-subtitle {
        font-size: 1.1rem;
        margin-bottom: 48px;
    }

    /* Header: horizontal nav on desktop */
    .nav-toggle {
        display: none;
    }

    .nav-links {
        position: static;
        width: auto;
        background: none;
        backdrop-filter: none;
        -webkit-backdrop-filter: none;
        flex-direction: row;
        align-items: center;
        padding: 0;
        gap: 28px;
        transform: none;
        border-left: none;
    }

    .nav-links a {
        font-size: 0.9rem;
        padding: 0;
    }

    .nav-cta {
        padding: 8px 20px !important;
        margin-top: 0;
    }

    /* Hero: side by side */
    #hero {
        padding: 140px 0 80px;
        min-height: 100vh;
    }

    .hero-grid {
        flex-direction: row;
        text-align: left;
        gap: 48px;
    }

    .hero-content {
        flex: 1;
    }

    .hero-badge img {
        width: 80px;
        height: 80px;
        margin: 0;
    }

    #hero h1 {
        font-size: 3.5rem;
    }

    .hero-subtitle {
        font-size: 1.35rem;
    }

    .hero-tagline {
        font-size: 1.1rem;
        max-width: 480px;
    }

    .rating {
        justify-content: flex-start;
    }

    .hero-free {
        font-size: 0.85rem;
    }

    .hero-image {
        flex: 1;
    }

    .hero-image img {
        max-width: 480px;
    }

    /* Features: 4 columns */
    .features-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 20px;
    }

    .feature-card {
        padding: 28px 24px;
    }

    .feature-card:hover {
        transform: translateY(-4px);
    }

    .feature-card h3 {
        font-size: 1.05rem;
    }

    .feature-card p {
        font-size: 0.88rem;
    }

    /* Screenshots */
    .screenshots-gallery {
        gap: 32px;
    }

    .screenshots-gallery figure {
        max-width: 280px;
    }

    .screenshots-gallery figcaption {
        font-size: 0.9rem;
    }

    /* Pricing */
    .pricing-grid {
        max-width: 720px;
        gap: 24px;
    }

    .pricing-card {
        padding: 40px 32px;
    }

    .pricing-card:hover {
        transform: translateY(-4px);
    }

    .price-amount {
        font-size: 3rem;
    }

    .pricing-card li {
        font-size: 0.95rem;
    }

    /* FAQ */
    summary {
        padding: 20px 48px 20px 24px;
        font-size: 1rem;
    }

    summary::after {
        right: 20px;
        font-size: 1.4rem;
    }

    .faq-answer {
        padding: 0 24px 20px;
        font-size: 0.95rem;
        line-height: 1.7;
    }

    /* Footer: 4 columns */
    .footer-grid {
        grid-template-columns: 2fr 1fr 1fr 1fr;
        gap: 40px;
    }

    .footer-download {
        justify-content: flex-end;
    }

    .app-store-link img {
        height: 38px;
    }

    #features h2,
    #screenshots h2,
    #pricing h2,
    #faq h2,
    #contact h2 {
        font-size: 2.2rem;
        margin-bottom: 12px;
    }
}

/* =========================================
   LARGE DESKTOP (min-width: 1280px)
   ========================================= */
@media (min-width: 1280px) {
    #hero h1 {
        font-size: 4rem;
    }

    .hero-image img {
        max-width: 540px;
    }
}