/* ===== 旺旺商聊 - 全新设计系统 ===== */
:root {
    --primary: #ff6b35;
    --primary-hover: #e55a2b;
    --primary-light: #fff0eb;
    --primary-soft: rgba(255, 107, 53, 0.08);
    --bg: #fafbfc;
    --bg-alt: #f0f2f5;
    --surface: #ffffff;
    --surface-hover: #f8f9fa;
    --text: #1a1a2e;
    --text-secondary: #5a6270;
    --text-muted: #949bab;
    --border: #e8eaef;
    --border-light: #f0f1f4;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.08);
    --shadow-xl: 0 24px 60px rgba(0,0,0,0.12);
    --radius-sm: 8px;
    --radius: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --max-width: 1200px;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid var(--border-light);
    transition: all 0.3s;
}
.navbar.scrolled { box-shadow: var(--shadow-md); }
.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    height: 64px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text);
    font-weight: 700;
    font-size: 20px;
}
.logo-icon {
    width: 38px; height: 38px;
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    color: white;
}
.logo-text span { color: var(--primary); }
.nav-links { display: flex; gap: 8px; align-items: center; }
.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 15px;
    padding: 8px 18px;
    border-radius: var(--radius-sm);
    transition: all 0.2s;
    font-weight: 500;
}
.nav-links a:hover { color: var(--primary); background: var(--primary-soft); }
.nav-links a.active { color: var(--primary); background: var(--primary-soft); font-weight: 600; }

/* ===== 按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: var(--radius);
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.25s;
    cursor: pointer;
    border: none;
    white-space: nowrap;
}
.btn-primary {
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    color: #fff;
    box-shadow: 0 4px 16px rgba(255,107,53,0.3);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 28px rgba(255,107,53,0.4);
}
.btn-outline {
    background: transparent;
    color: var(--text);
    border: 2px solid var(--border);
}
.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: var(--primary-soft);
}
.btn-lg { padding: 16px 36px; font-size: 17px; border-radius: var(--radius-lg); }
.btn-sm { padding: 8px 20px; font-size: 14px; }
.btn-icon { width: 20px; height: 20px; }

/* ===== Hero Section ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 100px 24px 80px;
    position: relative;
    overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute;
    top: -50%; right: -20%;
    width: 800px; height: 800px;
    background: radial-gradient(circle, rgba(255,107,53,0.06) 0%, transparent 70%);
    border-radius: 50%;
}
.hero::after {
    content: '';
    position: absolute;
    bottom: -30%; left: -10%;
    width: 600px; height: 600px;
    background: radial-gradient(circle, rgba(255,159,67,0.05) 0%, transparent 70%);
    border-radius: 50%;
}
.hero-container {
    max-width: var(--max-width);
    margin: 0 auto;
    width: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    position: relative;
    z-index: 1;
}
.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    background: var(--primary-light);
    border-radius: 50px;
    font-size: 13px;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 24px;
}
.hero-badge .dot {
    width: 8px; height: 8px;
    background: var(--primary);
    border-radius: 50%;
    animation: blink 1.5s ease-in-out infinite;
}
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0.3; } }
.hero-title {
    font-size: 56px;
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.02em;
    margin-bottom: 20px;
    color: var(--text);
}
.hero-title .highlight {
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-desc {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 36px;
    max-width: 480px;
}
.hero-btns { display: flex; gap: 14px; align-items: center; flex-wrap: wrap; }

/* Hero 右侧预览卡片 */
.hero-visual {
    position: relative;
    display: flex;
    justify-content: center;
}
.preview-card {
    width: 380px;
    background: var(--surface);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border-light);
    overflow: hidden;
    animation: float-card 4s ease-in-out infinite;
}
@keyframes float-card {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}
.preview-header {
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    padding: 18px 20px;
    display: flex;
    align-items: center;
    gap: 10px;
    color: white;
}
.preview-header .dots { display: flex; gap: 6px; }
.preview-header .dots span {
    width: 10px; height: 10px;
    border-radius: 50%;
    background: rgba(255,255,255,0.5);
}
.preview-header .dots span:first-child { background: rgba(255,255,255,0.9); }
.preview-header .title-text {
    flex: 1;
    text-align: center;
    font-size: 14px;
    font-weight: 600;
}
.preview-body { padding: 20px; }
.preview-chat { display: flex; flex-direction: column; gap: 14px; }
.chat-row { display: flex; gap: 10px; align-items: flex-end; }
.chat-row.out { flex-direction: row-reverse; }
.chat-avatar {
    width: 36px; height: 36px;
    border-radius: 50%;
    background: #f0f1f4;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    flex-shrink: 0;
}
.chat-row.out .chat-avatar { background: var(--primary-soft); }
.chat-bubble {
    padding: 10px 16px;
    border-radius: 18px;
    background: #f5f6f8;
    font-size: 13px;
    max-width: 70%;
    line-height: 1.5;
    color: var(--text-secondary);
}
.chat-row.out .chat-bubble {
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    color: white;
}
.chat-bubble:first-of-type { border-bottom-left-radius: 6px; }
.chat-row.out .chat-bubble:first-of-type { border-bottom-right-radius: 6px; border-bottom-left-radius: 18px; }
.preview-input {
    margin-top: 14px;
    display: flex;
    gap: 8px;
    padding: 12px 16px;
    background: #f5f6f8;
    border-radius: var(--radius);
}
.preview-input span {
    flex: 1;
    color: var(--text-muted);
    font-size: 13px;
}
.preview-input svg { width: 20px; height: 20px; color: var(--primary); }
.preview-badge {
    position: absolute;
    top: -12px; right: -12px;
    background: #ef4444;
    color: white;
    font-size: 12px;
    font-weight: 700;
    padding: 5px 12px;
    border-radius: 50px;
    box-shadow: 0 4px 12px rgba(239,68,68,0.4);
    animation: badge-pop 2s ease-in-out infinite;
}
@keyframes badge-pop {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.08); }
}

/* ===== Stats Section ===== */
.stats-section {
    padding: 30px 24px 60px;
    position: relative;
}
.stats-grid {
    max-width: 900px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0;
    background: var(--surface);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-light);
    overflow: hidden;
}
.stat-item {
    text-align: center;
    padding: 32px 24px;
    position: relative;
}
.stat-item + .stat-item::before {
    content: '';
    position: absolute;
    left: 0; top: 20%; height: 60%;
    width: 1px;
    background: var(--border-light);
}
.stat-value {
    font-size: 36px;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
    margin-bottom: 8px;
}
.stat-label {
    font-size: 14px;
    color: var(--text-muted);
    font-weight: 500;
}

/* ===== Section 通用 ===== */
.section {
    padding: 80px 24px;
    position: relative;
}
.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto 56px;
}
.section-tag {
    display: inline-block;
    font-size: 13px;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 12px;
    padding: 4px 14px;
    background: var(--primary-soft);
    border-radius: 50px;
}
.section-title {
    font-size: 40px;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--text);
    margin-bottom: 14px;
}
.section-desc {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== Features Section ===== */
.features-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}
.feature-card {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    transition: all 0.3s;
    position: relative;
    overflow: hidden;
}
.feature-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    transform: scaleX(0);
    transition: transform 0.3s;
}
.feature-card:hover::before { transform: scaleX(1); }
.feature-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.feature-icon {
    width: 52px; height: 52px;
    background: var(--primary-soft);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    margin-bottom: 20px;
}
.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text);
}
.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== Benefits Section ===== */
.benefits-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}
.benefit-card {
    display: flex;
    gap: 20px;
    padding: 32px;
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    transition: all 0.3s;
}
.benefit-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}
.benefit-icon {
    width: 48px; height: 48px;
    background: var(--primary-soft);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    flex-shrink: 0;
}
.benefit-info h3 {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 6px;
}
.benefit-info p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===== CTA Section ===== */
.cta-section {
    padding: 60px 24px;
}
.cta-box {
    max-width: var(--max-width);
    margin: 0 auto;
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    border-radius: var(--radius-xl);
    padding: 64px 48px;
    text-align: center;
    color: white;
    position: relative;
    overflow: hidden;
}
.cta-box::before {
    content: '';
    position: absolute;
    inset: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.06'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    opacity: 0.5;
}
.cta-title {
    font-size: 36px;
    font-weight: 800;
    margin-bottom: 14px;
    position: relative;
}
.cta-desc {
    font-size: 17px;
    opacity: 0.9;
    margin-bottom: 32px;
    position: relative;
}
.cta-box .btn {
    background: white;
    color: var(--primary);
    font-weight: 700;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
    position: relative;
}
.cta-box .btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.2);
}
.cta-box .btn-outline-white {
    background: transparent;
    color: white;
    border: 2px solid rgba(255,255,255,0.5);
}
.cta-box .btn-outline-white:hover {
    background: rgba(255,255,255,0.1);
    border-color: white;
}

/* ===== Testimonial ===== */
.testimonial-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}
.testimonial-card {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 28px;
}
.testimonial-text {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 20px;
    font-style: italic;
}
.testimonial-author {
    display: flex;
    align-items: center;
    gap: 12px;
}
.testimonial-author .avatar {
    width: 40px; height: 40px;
    background: var(--primary-soft);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}
.testimonial-author .info h4 {
    font-size: 14px;
    font-weight: 600;
}
.testimonial-author .info p {
    font-size: 12px;
    color: var(--text-muted);
}

/* ===== Footer ===== */
.footer {
    background: var(--text);
    color: rgba(255,255,255,0.7);
    padding: 60px 24px 30px;
}
.footer-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}
.footer-brand h3 {
    font-size: 20px;
    color: white;
    margin-bottom: 12px;
}
.footer-brand p {
    font-size: 14px;
    line-height: 1.7;
    opacity: 0.8;
}
.footer-links h4 {
    font-size: 14px;
    color: white;
    margin-bottom: 16px;
    font-weight: 600;
}
.footer-links a {
    display: block;
    color: rgba(255,255,255,0.6);
    text-decoration: none;
    font-size: 14px;
    margin-bottom: 10px;
    transition: color 0.2s;
}
.footer-links a:hover { color: var(--primary); }
.footer-bottom {
    max-width: var(--max-width);
    margin: 0 auto;
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 13px;
}

/* ===== 下载页 ===== */
.download-page-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 100px 24px 60px;
}
.download-wrapper {
    max-width: 560px;
    width: 100%;
}
.download-card {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    padding: 48px;
    box-shadow: var(--shadow-lg);
}
.download-header {
    text-align: center;
    margin-bottom: 36px;
}
.download-logo {
    width: 72px; height: 72px;
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 34px;
    color: white;
    margin: 0 auto 20px;
    box-shadow: 0 8px 28px rgba(255,107,53,0.3);
}
.download-header h1 {
    font-size: 28px;
    font-weight: 800;
    margin-bottom: 8px;
}
.download-header .subtitle {
    font-size: 14px;
    color: var(--text-muted);
}
.version-info {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-bottom: 28px;
}
.version-item {
    text-align: center;
    padding: 16px 12px;
    background: var(--bg-alt);
    border-radius: var(--radius);
}
.version-item .label {
    display: block;
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 4px;
}
.version-item .val {
    font-size: 16px;
    font-weight: 700;
    color: var(--primary);
}
.download-form { margin-bottom: 24px; }
.platform-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 24px;
}
.platform-tab {
    flex: 1;
    padding: 12px;
    text-align: center;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.2s;
    background: white;
}
.platform-tab:hover { border-color: var(--primary); }
.platform-tab.active {
    border-color: var(--primary);
    background: var(--primary-soft);
    color: var(--primary);
}
.platform-tab .tab-icon { font-size: 20px; display: block; margin-bottom: 6px; }
.download-btn-big {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    width: 100%;
    padding: 18px;
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 17px;
    font-weight: 700;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.3s;
    box-shadow: 0 4px 20px rgba(255,107,53,0.35);
}
.download-btn-big:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 32px rgba(255,107,53,0.45);
}
.download-btn-big svg { width: 22px; height: 22px; }
.system-req {
    margin-top: 28px;
    padding-top: 24px;
    border-top: 1px solid var(--border-light);
}
.system-req h3 {
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 600;
    margin-bottom: 14px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.req-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
}
.req-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    color: var(--text-secondary);
    padding: 8px 12px;
    background: var(--bg-alt);
    border-radius: var(--radius-sm);
}
.req-item .check {
    color: #22c55e;
    font-weight: 700;
}
.back-link {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    margin-top: 24px;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 14px;
    transition: color 0.2s;
}
.back-link:hover { color: var(--primary); }
.back-link svg { width: 16px; height: 16px; }

/* ===== 404 页面 ===== */
.error-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 100px 24px;
    text-align: center;
}
.error-content { max-width: 500px; }
.error-visual {
    margin-bottom: 32px;
    position: relative;
}
.error-emoji {
    font-size: 100px;
    display: block;
    animation: error-float 3s ease-in-out infinite;
}
@keyframes error-float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}
.error-code {
    font-size: 72px;
    font-weight: 900;
    background: linear-gradient(135deg, var(--primary), #ff9f43);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 8px;
}
.error-title {
    font-size: 28px;
    font-weight: 800;
    margin-bottom: 12px;
    color: var(--text);
}
.error-message {
    font-size: 15px;
    color: var(--text-secondary);
    margin-bottom: 36px;
    line-height: 1.7;
}
.error-links { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

/* ===== 滚动动画 ===== */
.animate-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}
.animate-in.visible {
    opacity: 1;
    transform: translateY(0);
}
.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }
.delay-3 { transition-delay: 0.3s; }
.delay-4 { transition-delay: 0.4s; }

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
    .hero-container { grid-template-columns: 1fr; gap: 48px; text-align: center; }
    .hero-desc { max-width: 100%; margin-left: auto; margin-right: auto; }
    .hero-btns { justify-content: center; }
    .hero-visual { order: -1; }
    .preview-card { width: 320px; }
    .hero-title { font-size: 42px; }
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .benefits-grid { grid-template-columns: 1fr; }
    .testimonial-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
}
@media (max-width: 768px) {
    .hero-title { font-size: 34px; }
    .hero-desc { font-size: 15px; }
    .section-title { font-size: 30px; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); border-radius: var(--radius-lg); }
    .stat-item:nth-child(2)::before { display: none; }
    .stat-item { padding: 24px 16px; }
    .stat-value { font-size: 28px; }
    .features-grid { grid-template-columns: 1fr; }
    .cta-box { padding: 40px 24px; }
    .cta-title { font-size: 26px; }
    .download-card { padding: 32px 24px; }
    .version-info { grid-template-columns: repeat(3, 1fr); }
    .platform-tabs { flex-direction: column; }
    .hero-btns { flex-direction: column; }
    .hero-btns .btn { width: 100%; justify-content: center; }
}
@media (max-width: 480px) {
    .hero { padding: 80px 16px 40px; }
    .hero-title { font-size: 28px; }
    .section { padding: 50px 16px; }
    .section-title { font-size: 26px; }
    .preview-card { width: 100%; }
    .stats-grid { grid-template-columns: 1fr 1fr; gap: 0; }
    .stat-value { font-size: 24px; }
    .cta-title { font-size: 22px; }
    .nav-container { padding: 0 16px; }
}