/* ========================================
   易経AI - I Ching AI Landing Page Styles
   Redesigned with Hero Background Rotation
   ======================================== */

/* CSS Variables */
:root {
    --color-primary: #1a1a2e;
    --color-secondary: #16213e;
    --color-accent: #e94560;
    --color-gold: #c9a227;
    --color-text: #333333;
    --color-text-light: #666666;
    --color-bg: #ffffff;
    --color-bg-alt: #f8f9fa;
    --color-border: #e0e0e0;
    --font-main: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Hiragino Sans", "Noto Sans JP", sans-serif;
    --max-width: 1100px;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 5rem;
    --border-radius: 12px;
    --transition: 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    color: var(--color-text);
    background-color: var(--color-bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

ul {
    list-style: none;
}

/* Container */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Language Navigation */
.lang-nav {
    position: fixed;
    top: 0;
    right: 0;
    left: 0;
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--color-border);
}

.lang-link {
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
    color: var(--color-text-light);
    border-radius: 6px;
    transition: var(--transition);
}

.lang-link:hover {
    background: var(--color-bg-alt);
    color: var(--color-text);
}

.lang-link.active {
    background: var(--color-primary);
    color: white;
}

/* ========================================
   Hero Section with Rotating Background
   ======================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: calc(var(--spacing-xl) + 60px) var(--spacing-md) var(--spacing-xl);
    overflow: hidden;
}

/* Background Images Container */
.hero-backgrounds {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    background: #000;
}

.hero-bg-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center top;
    opacity: 0;
    animation: heroFade 18s infinite;
}

.hero-bg-image::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        135deg,
        rgba(0, 0, 0, 0.45) 0%,
        rgba(0, 0, 0, 0.5) 50%,
        rgba(0, 0, 0, 0.55) 100%
    );
}

.hero-bg-image:nth-child(1) { animation-delay: 0s; }
.hero-bg-image:nth-child(2) { animation-delay: 6s; }
.hero-bg-image:nth-child(3) { animation-delay: 12s; }

@keyframes heroFade {
    0%, 25% { opacity: 1; }
    33.33%, 91.67% { opacity: 0; }
    100% { opacity: 1; }
}

/* Hero Content */
.hero-content {
    position: relative;
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-lg);
    max-width: 1200px;
    width: 100%;
    color: white;
}

.hero-text {
    flex: 1;
    text-align: left;
    max-width: 550px;
}

.hero-icon {
    margin-bottom: var(--spacing-md);
}

.hero-icon img {
    width: 80px;
    height: 80px;
    border-radius: 18px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
}

.hero-title {
    font-size: clamp(2.2rem, 6vw, 3.5rem);
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    letter-spacing: 0.03em;
}

.hero-tagline {
    font-size: clamp(1.1rem, 3vw, 1.5rem);
    color: var(--color-gold);
    margin-bottom: var(--spacing-md);
    font-weight: 500;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.15rem);
    opacity: 0.95;
    margin-bottom: var(--spacing-lg);
    line-height: 1.9;
    font-weight: 400;
}

/* Hero Screenshot */
.hero-screenshot {
    flex: 0 0 auto;
    position: relative;
}

.hero-screenshot img {
    width: 280px;
    height: auto;
    border-radius: 36px;
    box-shadow: 0 30px 80px rgba(0, 0, 0, 0.5);
    animation: floatPhone 4s ease-in-out infinite;
}

@keyframes floatPhone {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

/* Screenshot Carousel Dots */
.screenshot-dots {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-top: var(--spacing-sm);
}

.screenshot-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.4);
    cursor: pointer;
    transition: var(--transition);
}

.screenshot-dot.active {
    background: var(--color-gold);
    transform: scale(1.2);
}

.screenshot-dot:hover {
    background: rgba(255, 255, 255, 0.8);
}

/* CTA Button */
.cta-button {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    background: white;
    color: var(--color-primary);
    font-size: 1rem;
    font-weight: 600;
    border-radius: 50px;
    transition: var(--transition);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.25);
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(0, 0, 0, 0.35);
}

.apple-icon {
    width: 20px;
    height: 20px;
}

/* Responsive Hero */
@media (max-width: 900px) {
    .hero-content {
        flex-direction: column-reverse;
        text-align: center;
        gap: var(--spacing-md);
    }

    .hero-text {
        text-align: center;
        max-width: 600px;
    }

    .hero-screenshot img {
        width: 220px;
    }

    .hero-bg-image {
        background-position: center center;
    }
}

@media (max-width: 480px) {
    .hero-screenshot img {
        width: 180px;
    }
}

/* ========================================
   Section Styles
   ======================================== */
section {
    padding: var(--spacing-xl) var(--spacing-md);
}

section:nth-child(even) {
    background: var(--color-bg-alt);
}

.section-title {
    font-size: clamp(1.5rem, 5vw, 2rem);
    text-align: center;
    margin-bottom: var(--spacing-lg);
    color: var(--color-primary);
    position: relative;
}

.section-title::after {
    content: "";
    display: block;
    width: 60px;
    height: 3px;
    background: var(--color-gold);
    margin: var(--spacing-sm) auto 0;
    border-radius: 2px;
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.feature-card {
    background: white;
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.feature-card h3 {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-xs);
    color: var(--color-primary);
}

.feature-card p {
    font-size: 0.95rem;
    color: var(--color-text-light);
}

/* Use Cases */
.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
}

.use-case-item {
    background: white;
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--color-gold);
}

.use-case-category {
    display: inline-block;
    background: var(--color-primary);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    margin-bottom: var(--spacing-xs);
}

.use-case-item p {
    color: var(--color-text);
    font-size: 1rem;
}

/* Steps */
.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    counter-reset: step;
}

.step {
    text-align: center;
    padding: var(--spacing-md);
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: var(--color-primary);
    color: white;
    font-size: 1.5rem;
    font-weight: 700;
    border-radius: 50%;
    margin-bottom: var(--spacing-sm);
}

.step h3 {
    font-size: 1.1rem;
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.step p {
    font-size: 0.95rem;
    color: var(--color-text-light);
}

/* ========================================
   App Screenshots Section
   ======================================== */
.app-preview {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    color: white;
    overflow: hidden;
}

.app-preview .section-title {
    color: white;
}

.app-preview .section-title::after {
    background: var(--color-gold);
}

.screenshots-wrapper {
    overflow: hidden;
    padding: var(--spacing-md) 0;
}

.screenshots-container {
    display: flex;
    gap: var(--spacing-md);
    animation: scrollScreenshots 30s linear infinite;
    width: max-content;
}

.screenshots-container:hover {
    animation-play-state: paused;
}

.screenshot-item {
    flex: 0 0 auto;
}

.screenshot-item img {
    width: 240px;
    height: auto;
    border-radius: 28px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4);
    transition: transform 0.3s ease;
}

.screenshot-item img:hover {
    transform: scale(1.05);
}

@keyframes scrollScreenshots {
    0% {
        transform: translateX(0);
    }
    100% {
        transform: translateX(-50%);
    }
}

.preview-caption {
    text-align: center;
    margin-top: var(--spacing-md);
    opacity: 0.8;
    font-size: 0.95rem;
}

/* ========================================
   Testimonials Section (Text Only)
   ======================================== */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.testimonial {
    background: white;
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    position: relative;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.testimonial::before {
    content: """;
    position: absolute;
    top: 15px;
    left: 20px;
    font-size: 4rem;
    color: var(--color-gold);
    opacity: 0.3;
    font-family: Georgia, serif;
    line-height: 1;
}

.testimonial p {
    font-style: italic;
    color: var(--color-text);
    font-size: 1.05rem;
    line-height: 1.8;
    padding-top: var(--spacing-md);
}

.testimonial-author {
    margin-top: var(--spacing-sm);
    font-size: 0.9rem;
    color: var(--color-text-light);
    font-style: normal;
}

/* Target Users */
.target-list {
    max-width: 700px;
    margin: 0 auto;
}

.target-list li {
    padding: var(--spacing-sm) 0;
    padding-left: 2rem;
    position: relative;
    border-bottom: 1px solid var(--color-border);
}

.target-list li:last-child {
    border-bottom: none;
}

.target-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--color-gold);
    font-weight: bold;
}

/* Pricing */
.pricing-card {
    max-width: 500px;
    margin: 0 auto;
    background: white;
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    text-align: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

.pricing-desc {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-sm);
}

.pricing-trial {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--color-accent);
    margin-bottom: var(--spacing-sm);
}

.pricing-note {
    font-size: 0.85rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
}

.pricing-card .cta-button {
    background: var(--color-primary);
    color: white;
}

.pricing-card .cta-button:hover {
    background: var(--color-secondary);
}

/* Footer */
.footer {
    background: var(--color-primary);
    color: white;
    padding: var(--spacing-lg) var(--spacing-md);
    text-align: center;
}

.footer-brand {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.footer-tagline {
    color: var(--color-gold);
    margin-bottom: var(--spacing-md);
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.footer-links a {
    display: inline-block;
    padding: 0.5rem 1rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 6px;
    transition: var(--transition);
    font-size: 0.9rem;
}

.footer-links a:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.5);
}

.footer-company a {
    color: var(--color-gold);
    transition: var(--transition);
}

.footer-company a:hover {
    text-decoration: underline;
}

.footer-copy {
    font-size: 0.85rem;
    opacity: 0.7;
}

.footer-company {
    font-size: 0.9rem;
    opacity: 0.8;
    margin-bottom: var(--spacing-sm);
}

/* ========================================
   Stats Section
   ======================================== */
.stats {
    background: var(--color-primary);
    color: white;
    padding: var(--spacing-lg) var(--spacing-md);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-md);
    max-width: var(--max-width);
    margin: 0 auto;
    text-align: center;
}

.stat-number {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    font-weight: 700;
    color: var(--color-gold);
    margin-bottom: var(--spacing-xs);
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.9;
}

@media (max-width: 768px) {
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ========================================
   Hero Rating
   ======================================== */
.hero-rating {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
}

.hero-rating .stars {
    color: var(--color-gold);
    font-size: 1.2rem;
    letter-spacing: 2px;
}

.hero-rating .rating-text {
    font-size: 0.9rem;
    opacity: 0.9;
}

@media (max-width: 900px) {
    .hero-rating {
        justify-content: center;
    }
}

/* ========================================
   About Section
   ======================================== */
.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

.about-lead {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.about-text p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-light);
}

.about-list {
    list-style: none;
}

.about-list li {
    padding: var(--spacing-xs) 0;
    padding-left: 1.5rem;
    position: relative;
}

.about-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--color-gold);
    font-weight: bold;
}

.about-screenshot {
    width: 280px;
    border-radius: 32px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
    margin: 0 auto;
    display: block;
}

@media (max-width: 900px) {
    .about-content {
        grid-template-columns: 1fr;
    }

    .about-image {
        order: -1;
    }

    .about-screenshot {
        width: 220px;
    }
}

/* ========================================
   Example Section
   ======================================== */
.example {
    background: linear-gradient(135deg, var(--color-bg-alt) 0%, #e8e8e8 100%);
}

.example-content {
    max-width: 800px;
    margin: 0 auto;
}

.example-scenario {
    background: white;
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-lg);
    border-left: 4px solid var(--color-gold);
}

.example-scenario h3 {
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.example-scenario p {
    font-size: 1.1rem;
    color: var(--color-text);
}

.example-flow {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.flow-step {
    display: flex;
    gap: var(--spacing-md);
    align-items: flex-start;
}

.flow-number {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    background: var(--color-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
}

.flow-content {
    background: white;
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    flex: 1;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.flow-content h4 {
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
    font-size: 1rem;
}

.flow-content p {
    color: var(--color-text-light);
    font-size: 0.95rem;
    line-height: 1.7;
}

/* Example Response (Full Conversation) */
.example-response {
    background: white;
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    margin-top: var(--spacing-md);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.response-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--color-bg-alt);
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.response-label {
    font-weight: 600;
    color: var(--color-primary);
    font-size: 1.1rem;
}

.hexagram-result {
    background: var(--color-gold);
    color: white;
    padding: 0.3rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
}

.response-body {
    color: var(--color-text);
    line-height: 1.9;
}

.response-body h4 {
    color: var(--color-primary);
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    font-size: 1.1rem;
    border-left: 3px solid var(--color-gold);
    padding-left: var(--spacing-sm);
}

.response-body p {
    margin-bottom: var(--spacing-sm);
}

.response-body strong {
    color: var(--color-primary);
}

.response-body em {
    color: var(--color-accent);
    font-style: normal;
    font-weight: 500;
}

.response-body .quote {
    background: var(--color-bg-alt);
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-family: "Noto Serif JP", serif;
    font-size: 0.95em;
}

.response-details {
    margin-top: var(--spacing-md);
    border-top: 1px solid var(--color-border);
    padding-top: var(--spacing-md);
}

.response-details summary {
    cursor: pointer;
    color: var(--color-primary);
    font-weight: 600;
    padding: var(--spacing-sm);
    background: var(--color-bg-alt);
    border-radius: var(--border-radius);
    text-align: center;
    transition: var(--transition);
    list-style: none;
}

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

.response-details summary::after {
    content: " ▼";
    font-size: 0.8em;
}

.response-details[open] summary::after {
    content: " ▲";
}

.response-details summary:hover {
    background: var(--color-primary);
    color: white;
}

.response-full {
    padding-top: var(--spacing-md);
    color: var(--color-text);
    line-height: 1.9;
}

.response-full h4 {
    color: var(--color-primary);
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    font-size: 1.1rem;
    border-left: 3px solid var(--color-gold);
    padding-left: var(--spacing-sm);
}

.response-full p {
    margin-bottom: var(--spacing-sm);
}

.response-full em {
    color: var(--color-accent);
    font-style: normal;
    font-weight: 500;
}

.response-full .quote {
    background: var(--color-bg-alt);
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-family: "Noto Serif JP", serif;
    font-size: 0.95em;
}

/* ========================================
   FAQ Section
   ======================================== */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: white;
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-sm);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    overflow: hidden;
}

.faq-item summary {
    padding: var(--spacing-md);
    cursor: pointer;
    font-weight: 500;
    color: var(--color-primary);
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.faq-item summary::-webkit-details-marker {
    display: none;
}

.faq-item summary::after {
    content: "+";
    font-size: 1.5rem;
    color: var(--color-gold);
    transition: var(--transition);
}

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

.faq-item p {
    padding: 0 var(--spacing-md) var(--spacing-md);
    color: var(--color-text-light);
    line-height: 1.8;
}

/* ========================================
   Pricing Badge
   ======================================== */
.pricing-badge {
    display: inline-block;
    background: var(--color-gold);
    color: white;
    padding: 0.3rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

/* Responsive */
@media (max-width: 768px) {
    :root {
        --spacing-xl: 3rem;
        --spacing-lg: 2rem;
    }

    .sp-only {
        display: inline;
    }

    .lang-nav {
        justify-content: center;
    }
}

@media (min-width: 769px) {
    .sp-only {
        display: none;
    }
}

/* Print Styles */
@media print {
    .lang-nav,
    .cta-button,
    .hero-backgrounds {
        display: none;
    }

    .hero {
        background: none;
        color: var(--color-text);
        padding-top: var(--spacing-md);
        min-height: auto;
    }

    .hero-tagline {
        color: var(--color-text);
    }
}