/* ========================================
   Gate 芝麻官网 - 全局样式
   ======================================== */

/* CSS Variables */
:root {
    --primary-color: #1a73e8;
    --primary-dark: #1557b0;
    --secondary-color: #00d4aa;
    --accent-color: #ff6b35;
    --bg-dark: #0d1117;
    --bg-card: #161b22;
    --bg-light: #f8fafc;
    --text-primary: #ffffff;
    --text-secondary: #8b949e;
    --text-dark: #1f2937;
    --gradient-primary: linear-gradient(135deg, #1a73e8 0%, #00d4aa 100%);
    --gradient-accent: linear-gradient(135deg, #ff6b35 0%, #f7931a 100%);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
    --shadow-glow: 0 0 30px rgba(26, 115, 232, 0.3);
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-dark);
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: 1rem;
}

/* Navigation */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(13, 17, 23, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.header.scrolled {
    background: rgba(13, 17, 23, 0.98);
    box-shadow: var(--shadow-md);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
}

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

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

.nav-link:hover::after {
    width: 100%;
}

.nav-btn {
    background: var(--gradient-primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    transition: var(--transition);
}

.nav-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

/* Mobile Menu */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: var(--transition);
}

/* Hero Section */
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 0 80px;
    position: relative;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at 30% 20%, rgba(26, 115, 232, 0.15) 0%, transparent 50%),
                radial-gradient(ellipse at 70% 80%, rgba(0, 212, 170, 0.1) 0%, transparent 50%);
    z-index: 0;
}

.hero-grid {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image:
        linear-gradient(rgba(26, 115, 232, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(26, 115, 232, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    z-index: 0;
}

.hero-content {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-text {
    animation: fadeInLeft 1s ease;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(26, 115, 232, 0.1);
    border: 1px solid rgba(26, 115, 232, 0.3);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.875rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}

.hero-badge::before {
    content: '';
    width: 8px;
    height: 8px;
    background: var(--secondary-color);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

.hero-title {
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

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

.hero-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 500px;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    padding: 1rem 2rem;
    border-radius: 10px;
    font-weight: 600;
    font-size: 1rem;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-glow);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    padding: 1rem 2rem;
    border-radius: 10px;
    font-weight: 600;
    font-size: 1rem;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition);
    border: 2px solid rgba(255, 255, 255, 0.2);
    cursor: pointer;
}

.btn-secondary:hover {
    border-color: var(--primary-color);
    background: rgba(26, 115, 232, 0.1);
}

.hero-image {
    position: relative;
    animation: fadeInRight 1s ease;
}

.hero-image-wrapper {
    position: relative;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.hero-image-wrapper::before {
    content: '';
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    bottom: -2px;
    background: var(--gradient-primary);
    border-radius: 22px;
    z-index: -1;
    opacity: 0.5;
}

.hero-stats {
    display: flex;
    gap: 2rem;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

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

.stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--secondary-color);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Features Section */
#features {
    padding: 100px 0;
    background: var(--bg-card);
    position: relative;
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 3rem;
}

.section-tag {
    display: inline-block;
    background: rgba(26, 115, 232, 0.1);
    color: var(--primary-color);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.section-title {
    margin-bottom: 1rem;
}

.section-description {
    color: var(--text-secondary);
    font-size: 1.125rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--bg-dark);
    border-radius: var(--border-radius);
    padding: 2rem;
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
    animation: fadeInUp 0.6s ease forwards;
    opacity: 0;
}

.feature-card:nth-child(1) { animation-delay: 0.1s; }
.feature-card:nth-child(2) { animation-delay: 0.2s; }
.feature-card:nth-child(3) { animation-delay: 0.3s; }
.feature-card:nth-child(4) { animation-delay: 0.4s; }
.feature-card:nth-child(5) { animation-delay: 0.5s; }
.feature-card:nth-child(6) { animation-delay: 0.6s; }

.feature-card:hover {
    transform: translateY(-10px);
    border-color: rgba(26, 115, 232, 0.3);
    box-shadow: var(--shadow-glow);
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
}

.feature-title {
    margin-bottom: 1rem;
    font-size: 1.25rem;
}

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

/* Services Section */
#services {
    padding: 100px 0;
    background: var(--bg-dark);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.service-card {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.service-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.service-content {
    padding: 1.5rem;
}

.service-tag {
    display: inline-block;
    background: rgba(0, 212, 170, 0.1);
    color: var(--secondary-color);
    padding: 0.25rem 0.75rem;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.service-title {
    margin-bottom: 0.75rem;
}

.service-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 1rem;
}

.service-link {
    color: var(--primary-color);
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

.service-link:hover {
    gap: 10px;
}

/* Platform Section */
#platform {
    padding: 100px 0;
    background: var(--bg-card);
}

.platform-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.platform-image {
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.platform-text h2 {
    margin-bottom: 1.5rem;
}

.platform-text p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.platform-list {
    margin-bottom: 2rem;
}

.platform-list li {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.platform-list li::before {
    content: '✓';
    width: 24px;
    height: 24px;
    background: rgba(0, 212, 170, 0.1);
    color: var(--secondary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: 700;
}

/* Security Section */
#security {
    padding: 100px 0;
    background: var(--bg-dark);
    position: relative;
    overflow: hidden;
}

.security-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at 50% 50%, rgba(26, 115, 232, 0.05) 0%, transparent 70%);
}

.security-content {
    position: relative;
    z-index: 1;
}

.security-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 3rem;
}

.security-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
}

.security-card {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.security-card:hover {
    transform: translateY(-5px);
    border-color: rgba(26, 115, 232, 0.3);
}

.security-icon {
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin: 0 auto 1rem;
}

.security-title {
    font-size: 1rem;
    margin-bottom: 0.5rem;
}

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

/* FAQ Section */
#faq {
    padding: 100px 0;
    background: var(--bg-card);
}

.faq-container {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-dark);
    border-radius: var(--border-radius);
    margin-bottom: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.05);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 1.25rem 1.5rem;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 600;
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    color: var(--primary-color);
}

.faq-icon {
    font-size: 1.25rem;
    transition: var(--transition);
}

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

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer-content {
    padding: 0 1.5rem 1.5rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* CTA Section */
#cta {
    padding: 100px 0;
    background: var(--bg-dark);
    position: relative;
    overflow: hidden;
}

.cta-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-primary);
    opacity: 0.05;
}

.cta-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.cta-title {
    margin-bottom: 1.5rem;
}

.cta-description {
    color: var(--text-secondary);
    font-size: 1.125rem;
    margin-bottom: 2rem;
}

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

.cta-btn-primary {
    background: var(--gradient-primary);
    color: white;
    padding: 1rem 2.5rem;
    border-radius: 10px;
    font-weight: 600;
    font-size: 1.1rem;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.cta-btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-glow);
}

.cta-btn-secondary {
    background: transparent;
    color: var(--text-primary);
    padding: 1rem 2.5rem;
    border-radius: 10px;
    font-weight: 600;
    font-size: 1.1rem;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    transition: var(--transition);
    border: 2px solid rgba(255, 255, 255, 0.3);
    cursor: pointer;
}

.cta-btn-secondary:hover {
    border-color: white;
    background: rgba(255, 255, 255, 0.1);
}

/* App Download Section */
#download {
    padding: 100px 0;
    background: var(--bg-card);
}

.download-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.download-text h2 {
    margin-bottom: 1.5rem;
}

.download-text p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.download-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: var(--bg-dark);
    padding: 1rem 1.5rem;
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.download-btn:hover {
    border-color: var(--primary-color);
    background: rgba(26, 115, 232, 0.1);
}

.download-btn-icon {
    font-size: 1.5rem;
}

.download-btn-text {
    text-align: left;
}

.download-btn-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.download-btn-title {
    font-weight: 600;
}

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

.download-image img {
    max-width: 300px;
    margin: 0 auto;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
}

/* Footer */
.footer {
    background: var(--bg-dark);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding: 60px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr repeat(3, 1fr);
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-brand p {
    color: var(--text-secondary);
    margin-top: 1rem;
    font-size: 0.95rem;
}

.footer-title {
    font-size: 1rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.footer-links li {
    margin-bottom: 0.75rem;
}

.footer-links a {
    color: var(--text-secondary);
    font-size: 0.95rem;
    transition: var(--transition);
}

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

.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-copyright {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.footer-social {
    display: flex;
    gap: 1rem;
}

.footer-social a {
    width: 40px;
    height: 40px;
    background: var(--bg-card);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--primary-color);
    color: white;
}

/* Animations */
@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

/* Scroll to Top */
.scroll-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.25rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
    border: none;
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-top:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-glow);
}

/* Responsive Design */
@media (max-width: 992px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-text {
        order: 1;
    }

    .hero-image {
        order: 0;
    }

    .hero-description {
        margin: 0 auto 2rem;
    }

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

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

    .platform-content {
        grid-template-columns: 1fr;
    }

    .platform-image {
        order: -1;
    }

    .security-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .download-content {
        grid-template-columns: 1fr;
    }

    .download-image {
        order: -1;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: rgba(13, 17, 23, 0.98);
        flex-direction: column;
        padding: 2rem;
        gap: 1.5rem;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }

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

    .menu-toggle {
        display: flex;
    }

    .menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }

    .hero-stats {
        flex-direction: column;
        gap: 1rem;
    }

    .services-grid {
        grid-template-columns: 1fr;
    }

    .security-grid {
        grid-template-columns: 1fr;
    }

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

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-buttons {
        flex-direction: column;
    }

    .btn-primary,
    .btn-secondary {
        width: 100%;
        justify-content: center;
    }

    .cta-buttons {
        flex-direction: column;
    }

    .cta-btn-primary,
    .cta-btn-secondary {
        width: 100%;
        justify-content: center;
    }

    .download-buttons {
        flex-direction: column;
    }

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

/* Utility Classes */
.text-center { text-align: center; }
.text-primary { color: var(--primary-color); }
.text-secondary { color: var(--secondary-color); }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }