/* CSS Variables */
:root {
    --primary-purple: #8B5CF6;
    --primary-cyan: #06B6D4;
    --primary-blue: #3B82F6;
    --dark-bg: #0F0A1F;
    --dark-card: #1A1230;
    --dark-surface: #251A40;
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --gradient-primary: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
    --gradient-bg: linear-gradient(180deg, #0F0A1F 0%, #1A1035 50%, #0F0A1F 100%);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--dark-bg);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Animated Gradient Background */
.gradient-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-bg);
    z-index: -2;
}

.gradient-bg::before {
    content: '';
    position: absolute;
    top: 20%;
    left: 10%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(139, 92, 246, 0.15) 0%, transparent 70%);
    animation: float 15s ease-in-out infinite;
}

.gradient-bg::after {
    content: '';
    position: absolute;
    bottom: 20%;
    right: 10%;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(6, 182, 212, 0.12) 0%, transparent 70%);
    animation: float 12s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(30px, -30px); }
}

/* Header & Navigation */
header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(15, 10, 31, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(139, 92, 246, 0.1);
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.nav-icon {
    width: 36px;
    height: 36px;
    border-radius: 8px;
}

.logo-text {
    font-family: 'ZCOOL KuaiLe', cursive;
    font-size: 1.75rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

.lang-switch {
    background: rgba(139, 92, 246, 0.2);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.85rem;
}

.lang-switch:hover {
    background: rgba(139, 92, 246, 0.4);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 8rem 2rem 4rem;
}

.hero-content {
    text-align: center;
    max-width: 800px;
}

.app-icon-large {
    margin-bottom: 2rem;
}

.app-icon-large img {
    width: 180px;
    height: 180px;
    border-radius: 36px;
    box-shadow:
        0 20px 60px rgba(139, 92, 246, 0.3),
        0 0 100px rgba(6, 182, 212, 0.15);
    animation: iconGlow 4s ease-in-out infinite;
}

@keyframes iconGlow {
    0%, 100% {
        box-shadow:
            0 20px 60px rgba(139, 92, 246, 0.3),
            0 0 100px rgba(6, 182, 212, 0.15);
    }
    50% {
        box-shadow:
            0 25px 80px rgba(139, 92, 246, 0.4),
            0 0 120px rgba(6, 182, 212, 0.25);
    }
}

.app-title {
    font-family: 'ZCOOL KuaiLe', cursive;
    font-size: 5rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.25rem;
    letter-spacing: 0.1em;
    text-shadow: 0 0 60px rgba(139, 92, 246, 0.5);
}

.app-subtitle {
    font-size: 1.5rem;
    color: var(--text-secondary);
    font-weight: 300;
    letter-spacing: 0.3em;
    margin-bottom: 1.5rem;
}

.tagline {
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 2.5rem;
    line-height: 1.8;
}

/* Buttons */
.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

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

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 20px rgba(139, 92, 246, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(139, 92, 246, 0.5);
}

.btn-secondary {
    background: var(--dark-surface);
    color: var(--text-primary);
    border: 1px solid rgba(139, 92, 246, 0.3);
}

.btn-secondary:hover {
    background: var(--dark-card);
    border-color: var(--primary-purple);
}

/* Features Section */
.features {
    padding: 6rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.features h2,
.requirements h2,
.download h2 {
    font-family: 'ZCOOL KuaiLe', cursive;
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.5rem;
}

.feature-card {
    background: var(--dark-card);
    border: 1px solid rgba(139, 92, 246, 0.1);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: rgba(139, 92, 246, 0.3);
    box-shadow: 0 10px 40px rgba(139, 92, 246, 0.15);
}

.feature-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 1.5rem;
    background: var(--gradient-primary);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon svg {
    width: 30px;
    height: 30px;
    stroke: white;
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

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

.feature-card.feature-new {
    position: relative;
    border-color: rgba(6, 182, 212, 0.3);
    background: linear-gradient(135deg, var(--dark-card) 0%, rgba(6, 182, 212, 0.05) 100%);
}

.feature-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: linear-gradient(135deg, var(--primary-cyan), var(--primary-purple));
    color: white;
    font-size: 0.7rem;
    font-weight: 600;
    padding: 0.25rem 0.6rem;
    border-radius: 12px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Requirements Section */
.requirements {
    padding: 6rem 2rem;
    background: var(--dark-card);
}

.requirements-content {
    max-width: 800px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.requirement-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background: var(--dark-surface);
    border-radius: 16px;
    border: 1px solid rgba(139, 92, 246, 0.1);
}

.requirement-icon {
    width: 50px;
    height: 50px;
    background: rgba(139, 92, 246, 0.15);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.requirement-icon svg {
    width: 26px;
    height: 26px;
    fill: var(--primary-purple);
    stroke: var(--primary-purple);
}

.requirement-text h4 {
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
}

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

/* Download Section */
.download {
    padding: 6rem 2rem;
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}

.download-card {
    background: var(--dark-card);
    border: 1px solid rgba(139, 92, 246, 0.2);
    border-radius: 24px;
    padding: 3rem;
    position: relative;
    overflow: hidden;
}

.download-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
}

.version-info {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.version {
    background: rgba(139, 92, 246, 0.2);
    color: var(--primary-purple);
    padding: 0.4rem 0.8rem;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.85rem;
}

.release-date {
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

.btn-download {
    background: var(--gradient-primary);
    color: white;
    padding: 1.25rem 3rem;
    font-size: 1.1rem;
    box-shadow: 0 4px 25px rgba(139, 92, 246, 0.4);
}

.btn-download:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 35px rgba(139, 92, 246, 0.5);
}

.download-note {
    margin-top: 1.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.version-tag {
    background: linear-gradient(135deg, #10B981, #059669);
    color: white;
    padding: 0.4rem 0.8rem;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.85rem;
}

.whats-new {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(139, 92, 246, 0.15);
    text-align: left;
}

.whats-new h4 {
    font-size: 1rem;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

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

.whats-new li {
    color: var(--text-secondary);
    font-size: 0.9rem;
    padding: 0.4rem 0;
    padding-left: 1.25rem;
    position: relative;
}

.whats-new li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #10B981;
    font-weight: bold;
}

/* Version History Section */
.version-history {
    margin-top: 3rem;
    text-align: left;
}

.version-history h3 {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    text-align: center;
}

.version-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.version-item {
    background: var(--dark-card);
    border: 1px solid rgba(139, 92, 246, 0.1);
    border-radius: 16px;
    padding: 1.25rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.version-item-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    min-width: 180px;
}

.version-number {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1rem;
}

.version-date {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.version-description {
    flex: 1;
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin: 0;
    min-width: 200px;
}

.btn-small {
    padding: 0.6rem 1.25rem;
    font-size: 0.85rem;
    margin-left: auto;
}

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

/* FAQ Section */
.faq {
    padding: 6rem 2rem;
    max-width: 800px;
    margin: 0 auto;
}

.faq h2 {
    text-align: center;
    margin-bottom: 3rem;
}

.faq-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.faq-item {
    background: var(--dark-card);
    border: 1px solid rgba(139, 92, 246, 0.15);
    border-radius: 16px;
    padding: 1.5rem 2rem;
}

.faq-question {
    color: var(--text-primary);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.faq-answer {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.7;
}

.faq-answer p {
    margin-bottom: 0.75rem;
}

.faq-answer code {
    display: block;
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(139, 92, 246, 0.2);
    border-radius: 8px;
    padding: 1rem;
    font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
    font-size: 0.85rem;
    color: var(--primary-purple);
    margin: 0.75rem 0;
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-all;
}

.faq-answer ul,
.faq-answer ol {
    margin: 0.75rem 0;
    padding-left: 1.5rem;
}

.faq-answer li {
    margin-bottom: 0.5rem;
}

.faq-answer li code {
    display: inline;
    padding: 0.2rem 0.5rem;
    margin: 0;
    font-size: 0.8rem;
}

.faq-answer strong {
    color: var(--text-primary);
}

/* Footer */
footer {
    background: var(--dark-card);
    border-top: 1px solid rgba(139, 92, 246, 0.1);
    padding: 3rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.footer-logo {
    margin-bottom: 1.5rem;
}

.logo-text-small {
    font-family: 'ZCOOL KuaiLe', cursive;
    font-size: 1.5rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-tagline {
    display: block;
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 0.5rem;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1.5rem;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.3s ease;
}

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

.copyright {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .app-title {
        font-size: 3.5rem;
    }

    .app-subtitle {
        font-size: 1.2rem;
        letter-spacing: 0.2em;
    }

    .tagline {
        font-size: 1.25rem;
    }

    .description {
        font-size: 1rem;
    }

    .app-icon-large img {
        width: 140px;
        height: 140px;
    }

    .features h2,
    .requirements h2,
    .download h2 {
        font-size: 2rem;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }

    .footer-links {
        flex-direction: column;
        gap: 1rem;
    }

    .version-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .version-item-info {
        min-width: auto;
    }

    .version-description {
        min-width: auto;
    }

    .btn-small {
        margin-left: 0;
        width: 100%;
        justify-content: center;
    }
}

/* Selection Color */
::selection {
    background: rgba(139, 92, 246, 0.4);
    color: white;
}

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

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

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

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