/* Variables & Reset */
:root {
    /* Light Theme (Default) */
    --bg-color: #ffffff;
    --bg-secondary: #f5f6fa;
    --text-color: #1a1a2e;
    --text-secondary: #555;
    --text-muted: #666;

    /* Glass Effect Variables - Light */
    --glass-bg: rgba(0, 0, 0, 0.03);
    --glass-bg-hover: rgba(0, 0, 0, 0.06);
    --glass-border: rgba(0, 0, 0, 0.08);
    --glass-border-hover: rgba(0, 0, 0, 0.15);

    /* Header & UI Elements */
    --header-bg: rgba(255, 255, 255, 0.85);
    --button-text-color: white;
    --card-glow: 0 8px 32px 0 rgba(106, 17, 203, 0.1);

    /* Text Gradients & Colors */
    --heading-gradient: linear-gradient(135deg, #1a1a2e 0%, #4a4a6a 100%);
    --primary-gradient: linear-gradient(135deg, #6a11cb 0%, #2575fc 100%);
    --secondary-gradient: linear-gradient(135deg, #ff00cc 0%, #333399 100%);

    /* Specific Elements */
    --faq-bg: rgba(0, 0, 0, 0.03);
    --faq-text: #444;
    --avatar-bg: #f0f0f0;
    --avatar-border: #ffffff;
    --code-bg: rgba(37, 117, 252, 0.1);

    /* Language Switcher & Toggle */
    --control-bg: rgba(0, 0, 0, 0.05);
    --control-border: rgba(0, 0, 0, 0.1);
    --control-hover: rgba(0, 0, 0, 0.08);
    --control-active: rgba(0, 0, 0, 0.15);

    --font-main: 'Inter', sans-serif;

    /* Hero Glow */
    --hero-glow-opacity: 0.08;
}

:root[data-theme="dark"] {
    --bg-color: #0d0d12;
    --bg-secondary: #16161d;
    --text-color: #e0e0e0;
    --text-secondary: #aaa;
    --text-muted: #888;

    /* Glass Effect Variables - Dark */
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-bg-hover: rgba(255, 255, 255, 0.07);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-border-hover: rgba(255, 255, 255, 0.2);

    /* Header & UI Elements */
    --header-bg: rgba(13, 13, 18, 0.7);
    --button-text-color: white;
    --card-glow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);

    /* Text Gradients & Colors */
    --heading-gradient: linear-gradient(to right, #fff, #aaa);

    /* Specific Elements */
    --faq-bg: rgba(0, 0, 0, 0.2);
    --faq-text: #ccc;
    --avatar-bg: #222;
    --avatar-border: #0d0d12;
    --code-bg: rgba(37, 117, 252, 0.2);

    /* Language Switcher & Toggle */
    --control-bg: rgba(255, 255, 255, 0.05);
    --control-border: rgba(255, 255, 255, 0.1);
    --control-hover: rgba(255, 255, 255, 0.08);
    --control-active: rgba(255, 255, 255, 0.12);

    /* Hero Glow */
    --hero-glow-opacity: 0.15;
}

/* System Preference Automatic Detection Removed to force Light Mode default */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease;
}

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

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

/* Utilities */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

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

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

/* Buttons */
.btn-primary-lg,
.btn-primary-md,
.btn-primary-sm,
.btn-secondary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 12px 24px;
    border-radius: 50px;
    font-weight: 600;
    transition: transform 0.2s, box-shadow 0.2s;
    cursor: pointer;
}

.btn-primary-lg {
    background: var(--primary-gradient);
    color: white;
    font-size: 1.1rem;
    box-shadow: 0 4px 15px rgba(106, 17, 203, 0.4);
}

.btn-primary-md {
    background: var(--primary-gradient);
    color: white;
    font-size: 1rem;
    padding: 10px 20px;
}

.btn-primary-sm {
    background: var(--primary-gradient);
    color: white;
    font-size: 0.9rem;
    padding: 8px 16px;
}

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

.btn-primary-lg:hover,
.btn-primary-md:hover,
.btn-primary-sm:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(106, 17, 203, 0.6);
}

/* Header */
.glass-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: 15px 0;
    background: var(--header-bg);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--glass-border);
    z-index: 1000;
    transition: background 0.3s ease;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--secondary-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Theme Toggle */
.theme-toggle {
    background: var(--control-bg);
    border: 1px solid var(--glass-border);
    border-radius: 9px;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--text-color);
    font-size: 1.1rem;
    transition: all 0.3s ease;
    margin-right: 5px;
}

.theme-toggle:hover {
    background: var(--control-hover);
    transform: rotate(15deg);
}

/* Language Switcher */
.lang-switcher {
    display: flex;
    gap: 4px;
    background: var(--control-bg);
    border: 1px solid var(--control-border);
    border-radius: 12px;
    padding: 3px;
}

.lang-btn {
    background: transparent;
    border: none;
    border-radius: 9px;
    padding: 5px 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    line-height: 1;
    opacity: 0.6;
}

.lang-btn:hover {
    opacity: 0.9;
    background: var(--control-hover);
}

.lang-btn.active {
    opacity: 1;
    background: var(--control-active);
    box-shadow: 0 0 8px rgba(106, 17, 203, 0.2);
}

/* Hero Section */
.hero {
    position: relative;
    padding: 150px 0 100px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    overflow: hidden;
}

.hero-bg-glow {
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(106, 17, 203, var(--hero-glow-opacity)) 0%, rgba(13, 13, 18, 0) 70%);
    z-index: -1;
    animation: rotate 20s linear infinite;
}

@keyframes rotate {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.badge-new {
    display: inline-block;
    padding: 5px 15px;
    background: rgba(37, 117, 252, 0.15);
    border: 1px solid rgba(37, 117, 252, 0.4);
    border-radius: 20px;
    font-size: 0.85rem;
    color: #2575fc;
    margin-bottom: 20px;
}

.hero h1 {
    font-size: 3.5rem;
    line-height: 1.1;
    margin-bottom: 20px;
    background: var(--heading-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

.hero-cta-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 40px;
}

.sub-cta {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-left: 10px;
}

.social-proof-hero {
    display: flex;
    align-items: center;
    gap: 15px;
}

.avatars .avatar {
    font-size: 1.5rem;
    margin-right: -10px;
    border: 2px solid var(--avatar-border);
    border-radius: 50%;
    background: var(--avatar-bg);
    display: inline-block;
    width: 40px;
    height: 40px;
    line-height: 36px;
    text-align: center;
}

.hero-image {
    perspective: 1000px;
}

.glass-card-hero {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 20px;
    box-shadow: var(--card-glow);
    transform: rotateY(-10deg) rotateX(5deg);
    transition: transform 0.5s ease;
}

.glass-card-hero:hover {
    transform: rotateY(0deg) rotateX(0deg);
}

.app-preview {
    width: 100%;
    border-radius: 10px;
    display: block;
}

/* Sections Common */
section {
    padding: 80px 0;
}

h2 {
    font-size: 2.5rem;
    margin-bottom: 40px;
    color: var(--text-color);
}

/* Glass Cards */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 30px;
    transition: transform 0.3s, background 0.3s;
}

.glass-card:hover {
    transform: translateY(-5px);
    background: var(--glass-bg-hover);
    border-color: var(--glass-border-hover);
}

/* Problem Section */
.problem-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.link-arrow {
    color: #2575fc;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 5px;
    margin-top: 20px;
}

.icon-glow {
    font-size: 2rem;
    color: #2575fc;
    text-shadow: 0 0 20px rgba(37, 117, 252, 0.4);
    margin-bottom: 15px;
}

/* Features Grid */
.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.feature-box i {
    font-size: 2.5rem;
    margin-bottom: 20px;
    display: block;
}

.feature-box h3,
.feature-box p {
    color: var(--text-color);
}

.feature-box p {
    color: var(--text-secondary);
}

/* Testimonials */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 30px;
}

.author {
    margin-top: 20px;
    display: flex;
    flex-direction: column;
}

.author strong {
    color: var(--text-color);
}

.author span {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* Pricing */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
    max-width: 900px;
    margin: 0 auto;
}

.pricing-card {
    text-align: center;
    position: relative;
}

.pricing-card.popular {
    border: 1px solid #6a11cb;
    box-shadow: 0 0 30px rgba(106, 17, 203, 0.2);
}

.badge-pop {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--primary-gradient);
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    color: white;
}

.price {
    font-size: 3rem;
    font-weight: 800;
    margin: 20px 0;
    color: var(--text-color);
}

.price span {
    font-size: 1rem;
    color: var(--text-muted);
    font-weight: 400;
}

.pricing-card ul {
    text-align: left;
    margin-bottom: 30px;
}

.pricing-card li {
    margin-bottom: 10px;
    display: flex;
    gap: 10px;
    color: var(--text-color);
}

/* CTA Section */
.glass-card-glow {
    background: linear-gradient(135deg, rgba(106, 17, 203, 0.1) 0%, rgba(37, 117, 252, 0.1) 100%);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 60px;
    text-align: center;
}

.glass-card-glow h2 {
    margin-bottom: 20px;
}

.glass-card-glow p {
    margin-bottom: 40px;
    font-size: 1.2rem;
    color: var(--text-color);
}

/* Footer */
footer {
    padding: 40px 0;
    border-top: 1px solid var(--glass-border);
    margin-top: 50px;
    color: var(--text-muted);
}

.footer-content {
    display: flex;
    justify-content: space-between;
}

.footer-links a {
    margin-left: 20px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .problem-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-cta-group {
        align-items: center;
    }

    .glass-card-hero {
        margin-top: 40px;
        transform: none;
    }

    .glass-card-hero:hover {
        transform: none;
    }
}

/* FAQ Section */
.faq-grid {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.faq-item {
    padding: 0;
    overflow: hidden;
    cursor: pointer;
}

.faq-question {
    width: 100%;
    background: transparent;
    border: none;
    padding: 20px;
    text-align: left;
    color: var(--text-color);
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: var(--font-main);
}

.faq-question i {
    transition: transform 0.3s;
}

.faq-item.active .faq-question i {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
    background: var(--faq-bg);
}

.faq-answer p {
    padding: 20px;
    color: var(--faq-text);
    font-size: 0.95rem;
}

/* Support Section */
.support-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    text-align: left;
}

.quick-fixes ul {
    list-style: none;
    margin-top: 20px;
}

.quick-fixes li {
    margin-bottom: 15px;
    padding-left: 20px;
    border-left: 3px solid #2575fc;
}

.quick-fixes code {
    background: var(--code-bg);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.9rem;
    font-family: monospace;
    color: #2575fc;
}

.contact-info {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: flex-start;
}

@media (max-width: 768px) {
    .support-content {
        grid-template-columns: 1fr;
    }

    .nav-right {
        gap: 8px;
    }

    .lang-switcher {
        gap: 2px;
        padding: 2px;
    }

    .lang-btn {
        padding: 4px 6px;
        font-size: 0.85rem;
    }
}

/* CJK (Chinese) Font Support */
body.lang-zh {
    font-family: 'Noto Sans SC', 'Inter', sans-serif;
    word-break: keep-all;
}

body.lang-zh h1,
body.lang-zh h2,
body.lang-zh h3 {
    font-family: 'Noto Sans SC', 'Inter', sans-serif;
    letter-spacing: 0.02em;
}