:root {
    --ent-blue: #001220;
    --ent-accent: #00f3ff;
    --col-orange: #1a0500;
    --col-accent: #ff4d00;
    --text-color: #ffffff;
    --font-heading: 'Outfit', sans-serif;
    --font-mono: 'Space Mono', monospace;
    --font-body: 'Noto Sans SC', sans-serif;
    --split-trans: 0.6s cubic-bezier(0.22, 1, 0.36, 1);
}

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

body {
    background: #000;
    font-family: var(--font-body);
    color: var(--text-color);
    height: 100vh;
    width: 100vw;
    overflow: hidden;
}

.global-nav {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    padding: 2rem;
    display: flex;
    justify-content: center;
    z-index: 50;
    pointer-events: none;
}

.nav-links {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 0.8rem 2rem;
    border-radius: 30px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
    display: flex;
    gap: 2rem;
    pointer-events: auto;
}

.nav-item {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s;
}

.nav-item:hover {
    color: white;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
}

.split-container {
    display: flex;
    width: 100%;
    height: 100%;
    position: relative;
    padding-top: 0;
}

.split {
    flex: 1;
    position: relative;
    height: 100%;
    transition: flex var(--split-trans);
    overflow: hidden;
    overflow-y: auto;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    padding-top: 140px; /* 增加padding以避开导航栏 */
    padding-bottom: 100px; /* 为底部Chat留出空间 */
}

.split:hover {
    flex: 3;
}

/* Specific Styles */
.split.left {
    background: var(--ent-blue);
    border-right: 1px solid rgba(255, 255, 255, 0.1);
}

.split.right {
    background: var(--col-orange);
    border-left: 1px solid rgba(255, 255, 255, 0.1);
}

.split-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0.3;
    z-index: 0;
    transition: opacity 0.5s;
}

.split.left .split-bg {
    background-image:
        linear-gradient(rgba(0, 243, 255, 0.1) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 243, 255, 0.1) 1px, transparent 1px);
    background-size: 50px 50px;
}

.split.right .split-bg {
    background-image: radial-gradient(circle, rgba(255, 77, 0, 0.2) 2px, transparent 0.5px);
    background-size: 30px 30px;
}

.split:hover .split-bg {
    opacity: 0.6;
}

/* Content */
.split-content {
    z-index: 10;
    text-align: center;
    width: 90%;
    max-width: 550px;
    opacity: 0.8;
    transition: all var(--split-trans);
    flex-shrink: 0;
}

.split:hover .split-content {
    opacity: 1;
    transform: scale(1.05);
}

.split-header {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 2px;
    margin-bottom: 2rem;
    color: rgba(255, 255, 255, 0.6);
    transition: color 0.3s;
}

.header-zh {
    font-size: 1rem;
    opacity: 0.7;
    display: block;
    margin-top: 0.2rem;
}

.split.left:hover .split-header {
    color: var(--ent-accent);
}

.split.right:hover .split-header {
    color: var(--col-accent);
}

/* Body Content (Hidden mostly when collapsed) */
.split-body {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.5s ease 0.1s;
    height: 0;
    overflow: hidden;
}

.split:hover .split-body {
    opacity: 1;
    transform: translateY(0);
    height: auto;
    overflow: visible;
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 3rem;
    font-weight: 800;
    line-height: 1;
    margin-bottom: 1rem;
    text-transform: uppercase;
}

.split.left .hero-title {
    color: white;
    text-shadow: 0 0 20px rgba(0, 243, 255, 0.3);
}

.split.right .hero-title {
    color: white;
    text-shadow: 0 0 20px rgba(255, 77, 0, 0.3);
}

.hero-text {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 1.5rem;
    line-height: 1.4;
}

.cta-btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    font-family: var(--font-mono);
    font-weight: bold;
    font-size: 0.85rem;
    text-transform: uppercase;
    border: 1px solid white;
    cursor: pointer;
    transition: all 0.3s;
    background: rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(5px);
}

.cta-btn.primary:hover {
    background: var(--ent-accent);
    color: #000;
    border-color: var(--ent-accent);
    box-shadow: 0 0 20px rgba(0, 243, 255, 0.5);
}

.cta-btn.secondary:hover {
    background: var(--col-accent);
    color: #000;
    border-color: var(--col-accent);
    box-shadow: 0 0 20px rgba(255, 77, 0, 0.5);
}

.metrics-grid {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 1.5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 1.5rem;
}

.metric-item {
    display: flex;
    flex-direction: column;
}

.metric-val {
    font-family: var(--font-mono);
    font-size: 1.6rem;
    font-weight: 700;
}

.split.left .metric-val {
    color: var(--ent-accent);
}

.split.right .metric-val {
    color: var(--col-accent);
}

.metric-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    opacity: 0.6;
    margin-top: 0.2rem;
}

/* Center Divider */
.center-divider {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 20;
    pointer-events: none;
    /* Let clicks pass */
}

.logo-box {
    background: #000;
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 1rem 2rem;
    border-radius: 4px;
    box-shadow: 0 0 30px rgba(0, 0, 0, 0.8);
}

.logo-text {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 1rem;
    color: white;
    letter-spacing: -1px;
}

/* Chat Floater */
.chat-floater {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 100;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 30px;
    padding: 0.5rem 1rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    width: 400px;
    transition: all 0.3s;
}

.chat-status {
    font-family: var(--font-mono);
    font-size: 0.6rem;
    color: rgba(255, 255, 255, 0.5);
    letter-spacing: 1px;
}

.chat-input-wrapper {
    display: flex;
    width: 100%;
}

#chat-input {
    flex: 1;
    background: transparent;
    border: none;
    color: white;
    font-family: var(--font-body);
    font-size: 0.9rem;
    outline: none;
}

#send-btn {
    background: transparent;
    border: none;
    color: white;
    cursor: pointer;
    font-weight: bold;
}

/* Language Toggle Float */
.lang-toggle-float {
    position: absolute;
    top: 2rem;
    right: 2rem;
    z-index: 100;
    font-family: var(--font-mono);
    color: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    font-size: 0.8rem;
}

.lang-opt.active {
    color: white;
    font-weight: bold;
}

/* Responsive */
@media (max-width: 768px) {
    .split-container {
        flex-direction: column;
        padding-top: 70px;
    }

    .split {
        width: 100%;
        min-height: 50vh;
        height: auto;
        padding-top: 30px;
        padding-bottom: 80px;
    }

    .split:hover {
        flex: 2;
    }

    .hero-title {
        font-size: 2rem;
    }

    .chat-floater {
        width: 90%;
        bottom: 1rem;
    }

    .nav-links {
        padding: 0.6rem 1rem;
        gap: 1rem;
    }

    .nav-item {
        font-size: 0.7rem;
    }
}