/* ============================================================
   CJ.Plug Website - Main Stylesheet
   Pure CSS, no framework dependencies
   ============================================================ */

/* ----- CSS Variables ----- */
:root {
    --color-bg: #0a0a0f;
    --color-bg-alt: #0f0f18;
    --color-surface: #16162a;
    --color-surface-hover: #1e1e38;
    --color-border: #252545;
    --color-text: #e2e8f0;
    --color-text-secondary: #94a3b8;
    --color-text-muted: #64748b;
    --color-primary: #6366f1;
    --color-primary-light: #818cf8;
    --color-primary-dark: #4f46e5;
    --color-accent: #22d3ee;
    --color-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #22d3ee 100%);
    --color-success: #10b981;
    --color-warning: #f59e0b;

    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', Consolas, monospace;

    --radius-sm: 6px;
    --radius: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;

    --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
    --shadow: 0 4px 24px rgba(0,0,0,0.4);
    --shadow-lg: 0 8px 48px rgba(0,0,0,0.5);
    --shadow-glow: 0 0 40px rgba(99,102,241,0.15);

    --max-width: 1200px;
    --nav-height: 68px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--nav-height);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    color: var(--color-text);
    background: var(--color-bg);
    overflow-x: hidden;
}

::selection {
    background: var(--color-primary);
    color: #fff;
}

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

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

.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* ----- Section Common ----- */
.section {
    padding: 100px 0;
}

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

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-tag {
    display: inline-block;
    padding: 5px 16px;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-primary-light);
    background: rgba(99,102,241,0.1);
    border: 1px solid rgba(99,102,241,0.25);
    border-radius: 50px;
    margin-bottom: 16px;
    letter-spacing: 0.02em;
}

.section-header h2 {
    font-size: 2.2rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
    background: var(--color-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-header p {
    font-size: 1.05rem;
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ----- Navbar ----- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--nav-height);
    background: rgba(10,10,15,0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(255,255,255,0.06);
    transition: background var(--transition), border-color var(--transition);
}

.navbar.scrolled {
    background: rgba(10,10,15,0.95);
    border-bottom-color: rgba(255,255,255,0.1);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 1.3rem;
    letter-spacing: -0.01em;
}

.logo-icon {
    font-size: 1.5rem;
    color: var(--color-primary);
}

.logo-dot {
    color: var(--color-primary);
}

/* Nav Links */
.nav-links {
    display: flex;
    gap: 32px;
}

.nav-links a {
    font-size: 0.92rem;
    color: var(--color-text-secondary);
    font-weight: 500;
    position: relative;
    padding: 4px 0;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width var(--transition);
}

.nav-links a:hover { color: var(--color-text); }
.nav-links a:hover::after { width: 100%; }

/* Nav Dropdown */
.nav-dropdown {
    position: relative;
}

.nav-dropdown-trigger {
    display: flex;
    align-items: center;
    gap: 5px;
    font-size: 0.92rem;
    color: var(--color-text-secondary);
    font-weight: 500;
    cursor: pointer;
    padding: 4px 0;
    user-select: none;
    transition: color var(--transition);
    white-space: nowrap;
}

.nav-dropdown-trigger:hover {
    color: var(--color-text);
}

.dropdown-caret {
    transition: transform var(--transition);
}

.nav-dropdown:hover .dropdown-caret {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: calc(100% + 12px);
    right: 0;
    min-width: 260px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 8px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all 0.2s ease;
    box-shadow: 0 8px 32px rgba(0,0,0,0.5);
    z-index: 100;
}

.nav-dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu a {
    display: block;
    padding: 10px 14px;
    font-size: 0.88rem;
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    transition: all var(--transition);
}

.dropdown-menu a:hover {
    background: rgba(99,102,241,0.1);
    color: var(--color-text);
}

.dropdown-menu a::after {
    display: none;
}

/* Mobile Toggle */
.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 1001;
}

.mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: var(--transition);
}

.mobile-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.mobile-toggle.active span:nth-child(2) { opacity: 0; }
.mobile-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ----- Hero ----- */
.hero {
    padding: 160px 0 100px;
    position: relative;
    text-align: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 60% at 50% 0%, rgba(99,102,241,0.12) 0%, transparent 60%),
        radial-gradient(ellipse 60% 50% at 80% 80%, rgba(34,211,238,0.06) 0%, transparent 60%);
    pointer-events: none;
}

.hero-badge {
    display: inline-block;
    padding: 6px 18px;
    font-size: 13px;
    font-weight: 500;
    color: var(--color-accent);
    background: rgba(34,211,238,0.1);
    border: 1px solid rgba(34,211,238,0.2);
    border-radius: 50px;
    margin-bottom: 28px;
    animation: fadeInUp 0.6s ease-out;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.18;
    letter-spacing: -0.03em;
    margin-bottom: 24px;
    animation: fadeInUp 0.6s ease-out 0.1s both;
}

.gradient-text {
    background: var(--color-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: 1.15rem;
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: 40px;
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 56px;
    animation: fadeInUp 0.6s ease-out 0.3s both;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 48px;
    flex-wrap: wrap;
    animation: fadeInUp 0.6s ease-out 0.4s both;
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.stat-num {
    font-size: 1.5rem;
    font-weight: 700;
    font-family: var(--font-mono);
    color: var(--color-text);
}

.stat-label {
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

/* ----- Buttons ----- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
}

.btn-primary {
    background: var(--color-gradient);
    color: #fff;
    box-shadow: 0 4px 20px rgba(99,102,241,0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 28px rgba(99,102,241,0.5);
}

.btn-outline {
    background: transparent;
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

.btn-outline:hover {
    border-color: var(--color-primary-light);
    background: rgba(99,102,241,0.06);
}

.btn-light {
    background: #fff;
    color: var(--color-bg);
    font-weight: 600;
}

.btn-light:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 24px rgba(255,255,255,0.2);
}

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

/* ----- Feature Cards ----- */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(400px circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(99,102,241,0.06), transparent);
    opacity: 0;
    transition: opacity var(--transition);
}

.feature-card:hover {
    border-color: rgba(99,102,241,0.4);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-icon {
    width: 52px;
    height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius);
    background: rgba(99,102,241,0.1);
    margin-bottom: 20px;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    color: var(--color-primary-light);
}

.feature-card h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--color-text);
}

.feature-card p {
    font-size: 0.92rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ----- Quickstart ----- */
.quickstart-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 28px;
}

.quickstart-step {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 36px 32px;
    text-align: center;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.quickstart-step:hover {
    border-color: rgba(99,102,241,0.4);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.quickstart-num {
    font-family: var(--font-mono);
    font-size: 3rem;
    font-weight: 800;
    color: var(--color-primary);
    opacity: 0.15;
    line-height: 1;
    margin-bottom: -16px;
}

.quickstart-icon {
    width: 56px;
    height: 56px;
    margin: 8px auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: rgba(99,102,241,0.1);
}

.quickstart-icon svg {
    width: 28px;
    height: 28px;
    color: var(--color-primary-light);
}

.quickstart-step h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--color-text);
}

.quickstart-step p {
    font-size: 0.92rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    max-width: 360px;
    margin: 0 auto;
}

/* ----- Highlights ----- */
.highlight-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.highlight-item {
    display: flex;
    gap: 20px;
    padding: 28px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: all var(--transition);
}

.highlight-item:hover {
    border-color: rgba(99,102,241,0.3);
    transform: translateX(4px);
}

.highlight-num {
    font-family: var(--font-mono);
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--color-primary-light);
    opacity: 0.4;
    line-height: 1;
    flex-shrink: 0;
}

.highlight-item h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.highlight-item p {
    font-size: 0.92rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ----- Screenshots ----- */
.screenshot-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 28px;
}

.screenshot-card {
    transition: all var(--transition);
}

.screenshot-card:hover {
    transform: translateY(-6px);
}

.screenshot-frame {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.screenshot-img {
    width: 100%;
    aspect-ratio: 16 / 10;
    object-fit: cover;
    display: block;
    cursor: pointer;
    transition: opacity var(--transition);
}

.screenshot-img:hover {
    opacity: 0.85;
}

.screenshot-caption {
    padding: 16px 20px;
    font-size: 0.92rem;
    color: var(--color-text-secondary);
    border-top: 1px solid var(--color-border);
}

/* ----- Lightbox ----- */
.lightbox {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: rgba(0, 0, 0, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    align-items: center;
    justify-content: center;
    cursor: pointer;
    animation: fadeIn 0.2s ease-out;
}

.lightbox.active {
    display: flex;
}

.lightbox-img {
    max-width: 90vw;
    max-height: 90vh;
    object-fit: contain;
    border-radius: var(--radius);
    cursor: default;
    box-shadow: 0 8px 64px rgba(0, 0, 0, 0.6);
}

.lightbox-close {
    position: absolute;
    top: 24px;
    right: 32px;
    font-size: 2.2rem;
    color: rgba(255, 255, 255, 0.7);
    cursor: pointer;
    transition: color var(--transition);
    line-height: 1;
    z-index: 1;
}

.lightbox-close:hover {
    color: #fff;
}

/* ----- Video Section ----- */
.video-wrapper {
    max-width: 900px;
    margin: 0 auto;
}

.video-container {
    position: relative;
    aspect-ratio: 16 / 9;
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: #000;
    border: 1px solid var(--color-border);
}

.video-container video {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
}

.video-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 20px;
    background: var(--color-bg-alt);
}

.play-btn {
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: rgba(99,102,241,0.15);
    cursor: pointer;
    transition: all var(--transition);
}

.play-btn svg {
    width: 48px;
    height: 48px;
    color: var(--color-primary-light);
}

.play-btn:hover {
    background: rgba(99,102,241,0.25);
    transform: scale(1.08);
}

.video-placeholder p {
    color: var(--color-text-muted);
    font-size: 0.92rem;
}

.video-placeholder code {
    background: var(--color-surface);
    padding: 2px 8px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.85em;
}

/* ----- Download ----- */
.download-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.download-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    position: relative;
    display: flex;
    flex-direction: column;
    transition: all var(--transition);
}

.download-card:hover {
    border-color: rgba(99,102,241,0.4);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.download-card:first-child {
    border-color: rgba(99,102,241,0.5);
    background: linear-gradient(180deg, rgba(99,102,241,0.06) 0%, var(--color-surface) 30%);
}

.download-badge {
    position: absolute;
    top: -1px;
    right: 24px;
    padding: 4px 14px;
    font-size: 0.78rem;
    font-weight: 600;
    color: #fff;
    background: var(--color-gradient);
    border-radius: 0 0 var(--radius-sm) var(--radius-sm);
}

.download-card h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.download-desc {
    font-size: 0.92rem;
    color: var(--color-text-secondary);
    margin-bottom: 20px;
    line-height: 1.6;
}

.download-features {
    list-style: none;
    margin-bottom: 24px;
    flex-grow: 1;
}

.download-features li {
    font-size: 0.88rem;
    color: var(--color-text-secondary);
    padding: 6px 0 6px 22px;
    position: relative;
}

.download-features li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 13px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--color-primary);
}

.download-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 0;
    border-top: 1px solid var(--color-border);
    margin-bottom: 20px;
    font-size: 0.85rem;
}

.download-version {
    font-family: var(--font-mono);
    color: var(--color-primary-light);
    font-weight: 600;
}

.download-size {
    color: var(--color-text-muted);
}

.code-block {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
    margin-bottom: 24px;
    overflow-x: auto;
}

.code-block code {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--color-accent);
    white-space: nowrap;
}

/* ----- CTA Banner ----- */
.cta-banner {
    padding: 80px 0;
    text-align: center;
    background: linear-gradient(135deg, rgba(99,102,241,0.15), rgba(34,211,238,0.08));
    border-top: 1px solid rgba(99,102,241,0.15);
    border-bottom: 1px solid rgba(99,102,241,0.15);
}

.cta-banner h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.cta-banner p {
    color: var(--color-text-secondary);
    margin-bottom: 28px;
    font-size: 1.05rem;
}

/* ----- Footer ----- */
.footer {
    padding: 64px 0 32px;
    background: var(--color-bg-alt);
    border-top: 1px solid var(--color-border);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 48px;
}

.footer-brand p {
    color: var(--color-text-muted);
    font-size: 0.9rem;
    margin-top: 12px;
    line-height: 1.6;
}

.footer-links h4 {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--color-text-muted);
    margin-bottom: 16px;
}

.footer-links a {
    display: block;
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    padding: 4px 0;
    transition: color var(--transition);
}

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

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 24px;
    border-top: 1px solid var(--color-border);
    font-size: 0.85rem;
    color: var(--color-text-muted);
    flex-wrap: wrap;
    gap: 8px;
}

.heart { color: var(--color-primary); }

/* ----- Animations ----- */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(24px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.animate-visible {
    animation: fadeInUp 0.6s ease-out both;
}

/* ----- Responsive ----- */
@media (max-width: 1024px) {
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
    .download-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .hero-title { font-size: 2.4rem; }
    .hero { padding: 120px 0 72px; }
    .section { padding: 72px 0; }
    .section-header h2 { font-size: 1.7rem; }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--color-bg);
        flex-direction: column;
        padding: 100px 32px 32px;
        gap: 20px;
        transition: right var(--transition);
        border-left: 1px solid var(--color-border);
    }

    .nav-links.active { right: 0; }

    .nav-links a {
        font-size: 1.05rem;
    }

    /* Mobile dropdown */
    .nav-dropdown-trigger {
        font-size: 1.05rem;
        color: var(--color-text-muted);
        cursor: default;
        pointer-events: none;
    }

    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        background: transparent;
        border: none;
        box-shadow: none;
        padding: 0 0 0 16px;
        min-width: auto;
    }

    .dropdown-menu a {
        font-size: 0.95rem;
        padding: 8px 0;
    }

    .dropdown-caret {
        display: none;
    }

    .mobile-toggle {
        display: flex;
    }

    .feature-grid { grid-template-columns: 1fr; }
    .quickstart-grid { grid-template-columns: 1fr; }
    .highlight-grid { grid-template-columns: 1fr; }
    .screenshot-grid { grid-template-columns: 1fr; }
    .download-grid { grid-template-columns: 1fr; }

    .hero-stats { gap: 24px; }
    .hero-actions { flex-direction: column; align-items: center; }

    .footer-grid { grid-template-columns: 1fr 1fr; gap: 28px; }
    .footer-bottom { flex-direction: column; text-align: center; }
}

@media (max-width: 480px) {
    .hero-title { font-size: 1.9rem; }
    .footer-grid { grid-template-columns: 1fr; }
}