:root {
    --bg-color: #030014;
    /* Deep Space Blue */
    --text-primary: #ffffff;
    --text-secondary: #b4bacf;
    --accent-gold: #FFD700;
    --accent-blue: #00f0ff;
    --accent-violet: #7000ff;

    --font-en: 'Inter', system-ui, -apple-system, sans-serif;
    --font-cn: 'Noto Sans SC', system-ui, -apple-system, sans-serif;

    --glass-surface: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-highlight: rgba(255, 255, 255, 0.2);
    --blur-strength: 40px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    font-family: var(--font-en);
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* --- Background (Three.js Canvas) --- */
#bg-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    background: radial-gradient(circle at center, #0a0a0a 0%, #000000 100%);
    /* Fallback / Base blend */
}

/* --- Navigation --- */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    padding: 24px 48px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 100;
    /* backdrop-filter: blur(10px); Removed */
    /* border-bottom: 1px solid rgba(255, 255, 255, 0.05); Removed */
    background: transparent;
}

.branding {
    display: flex;
    align-items: center;
    gap: 16px;
    cursor: pointer;
}

.logo-text {
    font-size: 2rem;
    font-weight: 700;
    color: #fff;
    letter-spacing: -0.02em;
}

/* Logo Mask Wrapper */
.logo-wrapper {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    /* Restored circular shape */
    overflow: hidden;
    /* clips content to circle */
    flex-shrink: 0;

    /* Subtle border to define the circle */
    box-shadow:
        0 0 0 1px rgba(255, 255, 255, 0.1),
        0 0 20px rgba(0, 240, 255, 0.2);

    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.3s;
}

.logo {
    width: 100%;
    height: 100%;
    object-fit: cover;
    /* Ensures it fills the circle */
    /* mix-blend-mode: screen; Removed */
    transition: opacity 0.3s;
    display: block;
    /* No scale, no filter */
}

.logo:hover {
    opacity: 0.9;
}

.logo-wrapper:hover {
    transform: scale(1.05);
    box-shadow:
        0 0 0 1px rgba(255, 255, 255, 0.3),
        0 0 30px rgba(0, 240, 255, 0.6),
        0 0 60px rgba(112, 0, 255, 0.4);
}

.lang-switch {
    display: flex;
    gap: 8px;
    background: rgba(255, 255, 255, 0.05);
    padding: 4px;
    border-radius: 100px;
    border: 1px solid var(--glass-border);
}

.lang-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    padding: 6px 16px;
    border-radius: 100px;
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.3s;
}

.lang-btn.active {
    background: rgba(255, 255, 255, 0.15);
    color: #fff;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.2);
}

/* --- Switcher Visibility --- */
.en,
.cn {
    display: none;
}

body[data-current-lang="en"] .en,
body[data-current-lang="cn"] .cn {
    display: inline-block;
}

body[data-current-lang="en"] div.en,
body[data-current-lang="cn"] div.cn {
    display: block;
}

body[data-current-lang="en"] span.en,
body[data-current-lang="cn"] span.cn {
    display: inline;
}

p.en,
p.cn {
    display: none;
}

body[data-current-lang="en"] p.en,
body[data-current-lang="cn"] p.cn {
    display: block;
}

.cn {
    font-family: var(--font-cn);
    font-weight: 400;
}

h1 .cn,
h2 .cn {
    font-weight: 700;
}

/* Bold Headers for CN */

/* --- Layout Utility --- */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    position: relative;
    z-index: 1;
}

.section {
    padding: 160px 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

/* --- Typography --- */
h1 {
    font-size: clamp(4rem, 8vw, 7rem);
    font-weight: 800;
    letter-spacing: -0.04em;
    line-height: 1.0;
    text-align: center;
    background: linear-gradient(180deg, #fff 20%, #ccc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 0 30px rgba(255, 255, 255, 0.2);
    margin-bottom: 2rem;
}

h2 {
    font-size: 3rem;
    font-weight: 700;
    letter-spacing: -0.03em;
    margin-bottom: 2rem;
    text-align: center;
    color: #fff;
}

h2 .cn {
    font-size: 2.5rem;
    line-height: 1.4;
}

h1 .cn {
    letter-spacing: -0.02em;
    text-shadow: 0 0 40px rgba(255, 255, 255, 0.3);
}

p.subtitle {
    font-size: 1.5rem;
    color: var(--text-secondary);
    text-align: center;
    max-width: 600px;
    margin: 0 auto 3rem auto;
    font-weight: 400;
}

/* --- Components: Glass Cards --- */
.card-glass {
    background: var(--glass-surface);
    backdrop-filter: blur(var(--blur-strength));
    border: 1px solid var(--glass-border);
    border-top: 1px solid var(--glass-highlight);
    border-radius: 24px;
    padding: 48px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s, box-shadow 0.3s;

    /* V8 Glow Physics */
    position: relative;
    overflow: hidden;
}

/* The Glow Light */
.card-glass::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: 24px;
    background: radial-gradient(600px circle at var(--mouse-x) var(--mouse-y),
            rgba(255, 255, 255, 0.06),
            transparent 40%);
    opacity: 0;
    transition: opacity 0.5s;
    pointer-events: none;
    z-index: -1;
}

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

.card-glass:hover {
    transform: translateY(-5px);
    box-shadow: 0 30px 60px rgba(0, 0, 0, 0.4), 0 0 20px rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.3);
}

/* --- Section 1: Hero --- */
.hero {
    min-height: 100vh;
    padding-top: 200px;
}

.btn-primary {
    display: inline-block;
    background: #fff;
    color: #000;
    padding: 16px 48px;
    border-radius: 100px;
    font-weight: 600;
    text-decoration: none;
    font-size: 1rem;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
}

.btn-primary:hover {
    transform: scale(1.05);
    box-shadow: 0 0 40px rgba(255, 255, 255, 0.5);
}

.btn-secondary {
    display: inline-block;
    color: #fff;
    padding: 16px 48px;
    border-radius: 100px;
    font-weight: 600;
    text-decoration: none;
    font-size: 1rem;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

/* --- Special Buttons --- */
.btn-gold {
    display: inline-block;
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
    color: #000;
    padding: 16px 48px;
    border-radius: 100px;
    font-weight: 700;
    text-decoration: none;
    font-size: 1rem;
    transition: all 0.3s ease;
    border: none;
    box-shadow: 0 0 20px rgba(255, 215, 0, 0.3);
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.btn-gold::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #FFA500 0%, #FFD700 100%);
    opacity: 0;
    z-index: -1;
    transition: opacity 0.3s;
}

.btn-gold:hover {
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 0 40px rgba(255, 215, 0, 0.6);
}

.btn-gold:hover::before {
    opacity: 1;
}

.btn-community {
    display: inline-block;
    background: rgba(0, 240, 255, 0.05);
    color: #fff;
    padding: 16px 48px;
    border-radius: 100px;
    font-weight: 600;
    text-decoration: none;
    font-size: 1rem;
    transition: all 0.3s ease;
    border: 1px solid var(--accent-blue);
    box-shadow: 0 0 10px rgba(0, 240, 255, 0.1);
}

.btn-community:hover {
    background: rgba(0, 240, 255, 0.15);
    transform: translateY(-2px);
    box-shadow: 0 0 30px rgba(0, 240, 255, 0.4);
    text-shadow: 0 0 10px rgba(0, 240, 255, 0.8);
}

.hero-actions {
    margin-top: 2rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* --- Section 2: Problem (Split Cards) --- */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    width: 100%;
    margin-top: 4rem;
}

.problem .card-glass {
    display: flex;
    flex-direction: column;
    justify-content: center;
    text-align: left;
}

.problem .en {
    font-size: 1.8rem;
    font-weight: 500;
    color: #fff;
}

.problem .cn {
    font-size: 1.6rem;
    line-height: 1.6;
}

.problem h2 {
    text-align: left;
    margin-bottom: 0;
}

/* --- Section 3: Values (Grid 3) --- */
.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    width: 100%;
    margin-top: 4rem;
}

.value-icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    display: block;
    background: linear-gradient(135deg, #FFD700, #FFA500);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.card-glass h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: #fff;
    font-weight: 700;
}

.card-glass p {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* --- Mechanism: Timeline --- */
.timeline {
    position: relative;
    width: 100%;
    max-width: 800px;
    margin-top: 4rem;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(180deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transform: translateX(-50%);
}

.timeline-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 3rem;
    position: relative;
}

.timeline-item:nth-child(even) {
    flex-direction: row-reverse;
}

.timeline-dot {
    position: absolute;
    left: 50%;
    width: 12px;
    height: 12px;
    background: #fff;
    border-radius: 50%;
    box-shadow: 0 0 10px #fff;
    transform: translateX(-50%);
    z-index: 2;
}

.timeline-content {
    background: var(--glass-surface);
    border: 1px solid var(--glass-border);
    padding: 16px 32px;
    border-radius: 100px;
    font-weight: 600;
    backdrop-filter: blur(10px);
    width: 40%;
    text-align: center;
}

/* --- Grid 4 --- */
.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    width: 100%;
}


/* --- Responsive Roles Grid --- */
.roles-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    max-width: 900px;
    margin: 0 auto;
}

/* --- Mobile --- */
@media (max-width: 768px) {
    h1 {
        font-size: 3.5rem;
    }

    h2 {
        font-size: 2rem;
    }

    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }

    .nav-links {
        display: none;
    }

    .timeline::before {
        left: 20px;
    }

    .timeline-item,
    .timeline-item:nth-child(even) {
        flex-direction: row;
        justify-content: flex-start;
        padding-left: 50px;
    }

    .timeline-dot {
        left: 20px;
    }

    .timeline-content {
        width: 100%;
        text-align: left;
    }

    .hero {
        padding-top: 150px;
        text-align: center;
    }

    .hero-actions {
        justify-content: center;
    }
}

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