/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* EchoBox app colors */
    --primary-color: #007AFF;
    --primary-hover: #0056CC;
    --primary-light: #E3F2FD;
    --success-color: #34C759;
    --danger-color: #FF3B30;
    --warning-color: #FF9500;
    
    /* App theme colors */
    --bg-primary: #FFFFFF;
    --bg-secondary: #F8F9FA;
    --bg-tertiary: #F1F3F4;
    --text-primary: #202124;
    --text-secondary: #5F6368;
    --text-tertiary: #9AA0A6;
    --border-color: #DADCE0;
    --border-light: #E0E0E0;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --shadow-light: rgba(0, 0, 0, 0.05);
    
    /* App specific colors */
    --slider-track: #E0E0E0;
    --slider-active: #007AFF;
    --slider-thumb: #FFFFFF;
    --input-bg: #FFFFFF;
    --input-border: #DADCE0;
    --input-focus: #007AFF;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #007AFF 0%, #0056CC 100%);
    --gradient-bg: linear-gradient(180deg, #FFFFFF 0%, #F8F9FA 100%);
    
    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;
    
    /* Border radius - app style */
    --radius-xs: 4px;
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* Shadows - app style */
    --shadow-xs: 0 1px 2px var(--shadow-light);
    --shadow-sm: 0 2px 4px var(--shadow-light);
    --shadow-md: 0 4px 8px var(--shadow-color);
    --shadow-lg: 0 8px 16px var(--shadow-color);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.2s ease;
    --transition-slow: 0.3s ease;
}

body {
    font-family: var(--font-family);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    overflow-x: hidden;
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-light);
    z-index: 1000;
    transition: var(--transition-normal);
    box-shadow: var(--shadow-xs);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-weight: 600;
    font-size: 1.25rem;
    color: var(--text-primary);
}

.logo-img {
    width: 120px;
    height: 120px;
    object-fit: contain;
    margin-right: var(--spacing-xs);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: var(--transition-fast);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-color);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-fast);
}

/* Hero Section */
.hero {
    padding: 0px 0 var(--spacing-xxl);
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: var(--bg-primary);
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xxl);
    align-items: center;
    max-width: 1000px;
    margin: 0 auto;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    color: var(--text-primary);
}

.hero-logo {
    width: 300px;
    height: 300px;
    object-fit: contain;
    margin-right: var(--spacing-md);
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateY(0);
    }
    40% {
        transform: translateY(-10px);
    }
    60% {
        transform: translateY(-5px);
    }
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--primary-color);
    font-weight: 500;
    margin-bottom: var(--spacing-md);
}

.hero-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    line-height: 1.7;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-fast);
    cursor: pointer;
    border: none;
    font-size: 14px;
    min-height: 44px;
    box-shadow: var(--shadow-sm);
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    border: 1px solid var(--primary-color);
}

.btn-primary:hover {
    background: var(--primary-hover);
    border-color: var(--primary-hover);
    transform: none;
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--input-bg);
    color: var(--text-primary);
    border: 1px solid var(--input-border);
}

.hero-buttons .btn-icon {
    display: none;
}

.btn-secondary:hover {
    background: var(--bg-secondary);
    border-color: var(--border-color);
    transform: none;
}

.btn-success {
    background: #34C759;
    color: white;
    border: 1px solid #34C759;
}

.btn-success:hover {
    background: #28A745;
    border-color: #28A745;
}

.btn-icon {
    width: 16px;
    height: 16px;
}

.hero-stats {
    display: flex;
    gap: var(--spacing-xl);
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* App Preview */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.app-preview {
    transform: perspective(1000px) rotateY(-5deg);
    transition: var(--transition-slow);
}

.app-preview:hover {
    transform: perspective(1000px) rotateY(0deg);
}

.app-window {
    width: 580px;
    background: #F5F5F7;
    border-radius: 28px;
    box-shadow: 0 22px 70px rgba(36, 37, 38, 0.12);
    overflow: hidden;
    border: 1px solid rgba(0, 0, 0, 0.06);
}

.app-window-header {
    background: #1479F2;
    color: white;
    padding: 24px 24px 18px;
}

.app-window-title {
    display: flex;
    align-items: center;
    gap: 16px;
}

.app-window-icon {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.18);
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.18);
    display: grid;
    place-items: center;
    font-size: 1.75rem;
    line-height: 1;
}

.app-window-title h1 {
    font-size: 1.55rem;
    margin-bottom: 8px;
}

.app-window-title p {
    margin: 0;
    color: rgba(255, 255, 255, 0.85);
    font-size: 0.96rem;
}

.player-panel {
    padding: 24px;
    background: white;
    border-bottom: 1px solid #E7E8EC;
}

.player-controls-row {
    display: grid;
    grid-template-columns: repeat(4, 56px) 1fr;
    gap: 16px;
    align-items: center;
    margin-bottom: 20px;
}

.player-btn {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    border: none;
    font-size: 1.1rem;
    color: white;
    cursor: pointer;
    display: grid;
    place-items: center;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.player-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 24px rgba(20, 121, 242, 0.18);
}

.player-btn.add {
    background: #2B69F8;
}

.player-btn.play {
    background: #34C759;
}

.player-btn.stop {
    background: #FF3B30;
}

.player-btn.extra {
    background: #505357;
}

.player-info {
    color: #6B7280;
    font-size: 0.98rem;
    padding-left: 12px;
}

.player-progress {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.progress-track {
    flex: 1;
    height: 10px;
    background: #E4E7EC;
    border-radius: 999px;
    overflow: hidden;
    margin-right: 16px;
}

.progress-fill {
    width: 8%;
    height: 100%;
    background: #1479F2;
    border-radius: 999px;
}

.progress-time {
    color: #9CA3AF;
    font-size: 0.9rem;
    white-space: nowrap;
}

.library-panel {
    padding: 24px;
}

.library-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 18px;
}

.library-label {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 6px;
}

.library-subtitle {
    color: #6B7280;
    font-size: 0.92rem;
}

.library-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.library-search {
    display: flex;
    align-items: center;
    gap: 10px;
    background: #F3F4F6;
    padding: 12px 16px;
    border-radius: 16px;
    margin-bottom: 18px;
}

.search-icon {
    font-size: 1rem;
    color: #9CA3AF;
}

.library-search input {
    width: 100%;
    border: none;
    background: transparent;
    outline: none;
    color: #374151;
    font-size: 0.98rem;
}

.library-table {
    border: 1px solid #E5E7EB;
    border-radius: 18px;
    overflow: hidden;
}

.table-row {
    display: grid;
    grid-template-columns: 1.5fr 0.8fr 0.8fr;
    gap: 16px;
    align-items: center;
    padding: 14px 18px;
    font-size: 0.95rem;
}

.table-header {
    background: #F8FAFC;
    color: #475569;
    font-weight: 600;
}

.table-row:not(.table-header) {
    background: white;
    color: #111827;
}

.table-row:not(.table-header):nth-child(odd) {
    background: #F9FAFB;
}

.table-row span {
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Features Section */
.features {
    padding: var(--spacing-xxl) 0;
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xxl);
}

.section-title {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 16px;
    color: var(--text-secondary);
    font-weight: 400;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    max-width: 1000px;
    margin: 0 auto;
}

.feature-card {
    background: var(--bg-primary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-fast);
    text-align: left;
}

.feature-card:hover {
    transform: none;
    box-shadow: var(--shadow-md);
    border-color: var(--border-color);
}


.feature-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    margin: 0 auto var(--spacing-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: white;
    transition: var(--transition-normal);
    position: relative;
}

.feature-card:hover .feature-icon {
    transform: scale(1.1);
}

/* Multi-format icon - music note */
.feature-card:nth-child(1) .feature-icon::before {
    content: " ";
    position: absolute;
    width: 16px;
    height: 16px;
    background: white;
    border-radius: 50%;
    top: 10px;
    left: 22px;
}

.feature-card:nth-child(1) .feature-icon::after {
    content: " ";
    position: absolute;
    width: 10px;
    height: 20px;
    background: white;
    top: 22px;
    left: 25px;
    border-radius: 0 0 4px 4px;
}

/* Playlist icon - list */
.feature-card:nth-child(2) .feature-icon::before {
    content: " ";
    position: absolute;
    width: 30px;
    height: 4px;
    background: white;
    top: 15px;
    left: 15px;
    border-radius: 2px;
}

.feature-card:nth-child(2) .feature-icon::after {
    content: " ";
    position: absolute;
    width: 30px;
    height: 4px;
    background: white;
    top: 25px;
    left: 15px;
    border-radius: 2px;
    box-shadow: 0 10px 0 white, 0 20px 0 white;
}

/* Search icon - magnifying glass */
.feature-card:nth-child(3) .feature-icon::before {
    content: " ";
    position: absolute;
    width: 20px;
    height: 20px;
    border: 3px solid white;
    border-radius: 50%;
    top: 12px;
    left: 15px;
}

.feature-card:nth-child(3) .feature-icon::after {
    content: " ";
    position: absolute;
    width: 8px;
    height: 3px;
    background: white;
    top: 32px;
    left: 32px;
    transform: rotate(45deg);
}

/* Progress bar icon */
.feature-card:nth-child(4) .feature-icon::before {
    content: " ";
    position: absolute;
    width: 35px;
    height: 6px;
    background: rgba(255,255,255,0.3);
    border-radius: 3px;
    top: 27px;
    left: 12px;
}

.feature-card:nth-child(4) .feature-icon::after {
    content: " ";
    position: absolute;
    width: 20px;
    height: 6px;
    background: white;
    border-radius: 3px;
    top: 27px;
    left: 12px;
}

/* Interface icon - window */
.feature-card:nth-child(5) .feature-icon::before {
    content: " ";
    position: absolute;
    width: 35px;
    height: 25px;
    border: 3px solid white;
    border-radius: 4px;
    top: 15px;
    left: 12px;
}

.feature-card:nth-child(5) .feature-icon::after {
    content: " ";
    position: absolute;
    width: 8px;
    height: 8px;
    background: white;
    border-radius: 50%;
    top: 19px;
    left: 18px;
    box-shadow: 15px 0 0 white;
}

.feature-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.feature-description {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Download Section */
.download {
    padding: var(--spacing-xl) 0;
    background: var(--bg-secondary);
}

.download-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.download-card {
    background: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.download-icon {
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
    display: grid;
    place-items: center;
    color: white;
    font-size: 1.4rem;
    line-height: 1;
}

.download-icon::before {
    content: '⬇️';
}

.download-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.download-description {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.download-requirements {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.requirement {
    background: var(--bg-secondary);
    padding: 4px 8px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.download-steps {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.download-steps code {
    background: var(--bg-secondary);
    padding: var(--spacing-xs);
    border-radius: var(--radius-sm);
    font-family: 'Monaco', 'Menlo', monospace;
    font-size: 0.9rem;
    border: 1px solid var(--border-color);
}

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

.system-requirements {
    background: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.requirements-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    text-align: center;
}

.requirements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.requirement-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.req-icon {
    width: 20px;
    height: 20px;
    background: var(--success-color);
    border-radius: 50%;
    flex-shrink: 0;
}

.req-text {
    color: var(--text-secondary);
}

/* About Section */
.about {
    padding: var(--spacing-xl) 0;
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-xl);
    align-items: start;
}

.about-text {
    font-size: 1.1rem;
    line-height: 1.7;
}

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

.about-features {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-lg);
}

.about-feature {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.feature-check {
    width: 20px;
    height: 20px;
    background: var(--success-color);
    border-radius: 50%;
    flex-shrink: 0;
}

.about-visual {
    background: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.version-badge {
    background: var(--gradient-primary);
    color: white;
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.version-number {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
}

.version-date {
    font-size: 0.9rem;
    opacity: 0.8;
}

.changelog h4 {
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.changelog ul {
    list-style: none;
    padding: 0;
}

.changelog li {
    padding: var(--spacing-xs) 0;
    color: var(--text-secondary);
    position: relative;
    padding-left: var(--spacing-md);
}

.changelog li::before {
    content: " ";
    position: absolute;
    left: 0;
    top: 8px;
    width: 6px;
    height: 6px;
    background: var(--primary-color);
    border-radius: 50%;
}

/* Footer */
.footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-xl) 0 var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.footer-section {
    text-align: center;
}

.footer-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    font-weight: 600;
    font-size: 1.1rem;
    margin-bottom: var(--spacing-sm);
}

.footer-logo-img {
    width: 80px;
    height: 80px;
    object-fit: contain;
    margin-right: var(--spacing-xs);
}

.footer-description {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.footer-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.footer-links {
    list-style: none;
    padding: 0;
}

.footer-links li {
    margin-bottom: var(--spacing-xs);
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition-fast);
}

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

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--bg-secondary);
        flex-direction: column;
        padding: var(--spacing-md);
        box-shadow: var(--shadow-md);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 3rem;
    }
    
    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .app-window {
        width: 300px;
        height: 450px;
    }
    
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .download-options {
        grid-template-columns: 1fr;
    }
    
    .requirements-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .app-window {
        width: 250px;
        height: 375px;
    }
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-text > * {
    animation: fadeInUp 0.8s ease backwards;
}

.hero-title { animation-delay: 0.1s; }
.hero-subtitle { animation-delay: 0.2s; }
.hero-description { animation-delay: 0.3s; }
.hero-buttons { animation-delay: 0.4s; }
.hero-stats { animation-delay: 0.5s; }

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.app-preview {
    animation: float 3s ease-in-out infinite;
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Custom scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-hover);
}