/* 重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #f59e0b;
    --accent-color: #10b981;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-dark: #111827;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-accent: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

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

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-img {
    height: 40px;
    width: auto;
    object-fit: contain;
}

.nav-logo h2 {
    color: var(--primary-color);
    font-weight: 700;
    font-size: 1.5rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

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

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    margin: 3px 0;
    transition: 0.3s;
}

/* 英雄区域 */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    overflow: hidden;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 2;
}

.hero-content {
    color: white;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1.5rem;
}

.highlight {
    background: var(--gradient-secondary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-left: 0.5rem;
    display: inline-block;
}

.hero-description {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    line-height: 1.8;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: var(--gradient-accent);
    color: white;
    box-shadow: var(--shadow-lg);
}

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

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

/* 手机模型 */
.phone-mockup {
    width: 300px;
    height: 600px;
    background: #1f2937;
    border-radius: 40px;
    padding: 20px;
    position: relative;
    box-shadow: var(--shadow-xl);
    margin: 0 auto;
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: white;
    border-radius: 30px;
    overflow: hidden;
    position: relative;
}

.app-interface {
    height: 100%;
    display: flex;
    flex-direction: column;
    background: #f8f9fa;
    position: relative;
}

/* 状态栏 */
.status-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 1rem;
    background: #000;
    color: white;
    font-size: 0.7rem;
    font-weight: 500;
}

/* 聊天头部 */
.chat-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background: white;
    border-bottom: 1px solid #e5e7eb;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.avatar {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.8rem;
    font-weight: 600;
}

.user-details .name {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 0.9rem;
}

.user-details .title {
    color: var(--text-secondary);
    font-size: 0.75rem;
}

.price-tag {
    background: var(--gradient-accent);
    color: white;
    padding: 0.4rem 0.8rem;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 600;
}

/* 聊天内容 */
.chat-content {
    flex: 1;
    padding: 1rem;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.chat-bubble {
    max-width: 85%;
    padding: 0.75rem 1rem;
    border-radius: 18px;
    font-size: 0.85rem;
    position: relative;
    animation: slideIn 0.5s ease;
}

.chat-bubble.user {
    background: var(--primary-color);
    color: white;
    align-self: flex-end;
    border-bottom-right-radius: 5px;
}

.chat-bubble.assistant {
    background: white;
    color: var(--text-primary);
    align-self: flex-start;
    border-bottom-left-radius: 5px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.chat-bubble.typing {
    background: white;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.message-text {
    margin-bottom: 0.25rem;
    line-height: 1.4;
}

.message-time {
    font-size: 0.7rem;
    opacity: 0.7;
    text-align: right;
}

.chat-bubble.assistant .message-time {
    text-align: left;
}

/* 知识内容卡片 */
.knowledge-content {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 0.75rem;
    margin: 0.5rem 0;
}

.knowledge-title {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.knowledge-points {
    color: var(--text-secondary);
    font-size: 0.8rem;
    line-height: 1.5;
}

/* 输入区域 */
.input-area {
    display: flex;
    align-items: center;
    padding: 1rem;
    background: white;
    border-top: 1px solid #e5e7eb;
    gap: 0.75rem;
}

.voice-btn, .send-btn {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.voice-btn {
    background: var(--bg-secondary);
    color: var(--text-secondary);
}

.voice-btn:hover {
    background: var(--primary-color);
    color: white;
}

.input-field {
    flex: 1;
}

.input-field input {
    width: 100%;
    border: 1px solid #e5e7eb;
    border-radius: 20px;
    padding: 0.75rem 1rem;
    font-size: 0.85rem;
    background: #f8f9fa;
    outline: none;
}

.send-btn {
    background: var(--primary-color);
    color: white;
}

.send-btn:hover {
    background: var(--primary-dark);
}

/* 语音消息样式 */
.voice-message {
    background: var(--primary-color) !important;
    color: white !important;
}

.voice-message-content {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 0;
}

.voice-icon {
    width: 24px;
    height: 24px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.voice-icon:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.1);
}

.voice-waveform {
    display: flex;
    align-items: center;
    gap: 2px;
    flex: 1;
}

.wave-bar {
    width: 3px;
    height: 12px;
    background: rgba(255, 255, 255, 0.6);
    border-radius: 2px;
    animation: waveAnimation 1.5s ease-in-out infinite;
}

.wave-bar:nth-child(1) { animation-delay: 0s; }
.wave-bar:nth-child(2) { animation-delay: 0.1s; }
.wave-bar:nth-child(3) { animation-delay: 0.2s; }
.wave-bar:nth-child(4) { animation-delay: 0.3s; }
.wave-bar:nth-child(5) { animation-delay: 0.4s; }
.wave-bar:nth-child(6) { animation-delay: 0.5s; }
.wave-bar:nth-child(7) { animation-delay: 0.6s; }
.wave-bar:nth-child(8) { animation-delay: 0.7s; }

.voice-duration {
    font-size: 0.7rem;
    opacity: 0.8;
    font-weight: 500;
}

/* 录音状态样式 */
.recording {
    background: #ff6b6b !important;
    color: white !important;
}

.recording-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.5rem 0;
}

.recording-indicator {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.recording-dot {
    width: 8px;
    height: 8px;
    background: white;
    border-radius: 50%;
    animation: recordingPulse 1s infinite;
}

.recording-timer {
    font-size: 0.7rem;
    font-weight: 600;
}

/* 语音识别状态 */
.voice-recognizing {
    background: #f8f9fa !important;
    color: var(--text-primary) !important;
}

.voice-recognizing-content {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 0;
}

.voice-recognizing-icon {
    width: 24px;
    height: 24px;
    background: var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.7rem;
    animation: voiceRecognizingPulse 1.5s infinite;
}

.recognizing-text {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.recognizing-dots {
    display: flex;
    gap: 3px;
}

.recognizing-dots span {
    width: 4px;
    height: 4px;
    background: var(--text-secondary);
    border-radius: 50%;
    animation: recognizingDots 1.4s infinite;
}

.recognizing-dots span:nth-child(2) {
    animation-delay: 0.2s;
}

.recognizing-dots span:nth-child(3) {
    animation-delay: 0.4s;
}

/* 录音状态栏 */
.recording-bar {
    background: #ff6b6b;
    color: white;
    padding: 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    animation: slideUp 0.3s ease;
}

.recording-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex: 1;
}

.recording-waveform {
    display: flex;
    align-items: center;
    gap: 2px;
}

.recording-waveform .wave-bar {
    width: 4px;
    height: 16px;
    background: rgba(255, 255, 255, 0.8);
    border-radius: 2px;
    animation: recordingWave 0.8s ease-in-out infinite;
}

.recording-waveform .wave-bar:nth-child(1) { animation-delay: 0s; }
.recording-waveform .wave-bar:nth-child(2) { animation-delay: 0.1s; }
.recording-waveform .wave-bar:nth-child(3) { animation-delay: 0.2s; }
.recording-waveform .wave-bar:nth-child(4) { animation-delay: 0.3s; }
.recording-waveform .wave-bar:nth-child(5) { animation-delay: 0.4s; }
.recording-waveform .wave-bar:nth-child(6) { animation-delay: 0.5s; }
.recording-waveform .wave-bar:nth-child(7) { animation-delay: 0.6s; }
.recording-waveform .wave-bar:nth-child(8) { animation-delay: 0.7s; }

.recording-text {
    font-size: 0.9rem;
    font-weight: 500;
}

.recording-timer {
    font-size: 0.9rem;
    font-weight: 600;
    font-family: 'Courier New', monospace;
}

.recording-actions {
    display: flex;
    gap: 0.5rem;
}

.recording-cancel, .recording-send {
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.recording-cancel {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.recording-cancel:hover {
    background: rgba(255, 255, 255, 0.3);
}

.recording-send {
    background: white;
    color: #ff6b6b;
}

.recording-send:hover {
    background: #f8f9fa;
    transform: scale(1.05);
}

/* 动画效果 */
@keyframes waveAnimation {
    0%, 100% {
        height: 8px;
        opacity: 0.6;
    }
    50% {
        height: 16px;
        opacity: 1;
    }
}

@keyframes recordingPulse {
    0%, 100% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.5;
        transform: scale(1.2);
    }
}

@keyframes voiceRecognizingPulse {
    0%, 100% {
        transform: scale(1);
        opacity: 1;
    }
    50% {
        transform: scale(1.1);
        opacity: 0.8;
    }
}

@keyframes recognizingDots {
    0%, 60%, 100% {
        transform: translateY(0);
        opacity: 0.4;
    }
    30% {
        transform: translateY(-8px);
        opacity: 1;
    }
}

@keyframes recordingWave {
    0%, 100% {
        height: 8px;
        opacity: 0.6;
    }
    50% {
        height: 20px;
        opacity: 1;
    }
}

@keyframes slideUp {
    from {
        transform: translateY(100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* 打字动画 */
.typing-animation {
    display: flex;
    gap: 3px;
    align-items: center;
}

.typing-animation span {
    width: 6px;
    height: 6px;
    background: var(--text-secondary);
    border-radius: 50%;
    animation: typing 1.4s infinite;
}

.typing-animation span:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-animation span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes typing {
    0%, 60%, 100% {
        transform: translateY(0);
    }
    30% {
        transform: translateY(-10px);
    }
}

/* 背景装饰 */
.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.gradient-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(40px);
    opacity: 0.3;
    animation: float 6s ease-in-out infinite;
}

.orb-1 {
    width: 300px;
    height: 300px;
    background: var(--gradient-secondary);
    top: 20%;
    left: 10%;
    animation-delay: 0s;
}

.orb-2 {
    width: 200px;
    height: 200px;
    background: var(--gradient-accent);
    top: 60%;
    right: 20%;
    animation-delay: 2s;
}

.orb-3 {
    width: 150px;
    height: 150px;
    background: var(--gradient-primary);
    bottom: 20%;
    left: 30%;
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-20px);
    }
}

/* 功能特色 */
.features {
    padding: 6rem 0;
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.section-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    background: white;
    padding: 2.5rem;
    border-radius: 20px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

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

.feature-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient-primary);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 2rem;
    color: white;
}

.feature-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.feature-description {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* 下载区域 */
.download {
    padding: 6rem 0;
    background: var(--bg-primary);
}

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

.download-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.download-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.8;
}

.download-stats {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
}

.stat {
    text-align: center;
}

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

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.platform-tabs-container {
    margin-bottom: 2rem;
    background: white;
    border-radius: 15px;
    padding: 1.5rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border: 2px solid var(--border-color);
}

.platform-tabs {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.platform-tab {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 15px;
    color: var(--text-primary);
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
    cursor: pointer;
    flex: 1;
}

.platform-tab:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.platform-tab.active {
    border-color: var(--primary-color);
    background: var(--primary-color);
    color: white;
}

.version-details {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
}

.version-details[style*="display: none"] {
    display: none !important;
}

.version-content {
    flex: 1;
}

.version-actions {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    min-width: 90px;
}

.download-action-btn {
    padding: 0.4rem 0.8rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 5px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.3rem;
    transition: all 0.3s ease;
    font-size: 0.85rem;
}

.download-action-btn:hover {
    background: #5a67d8;
    transform: translateY(-2px);
}

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

.qr-section .qr-code-display {
    width: 110px;
    height: 110px;
    margin: 0 auto 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.qr-section .qr-text {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin: 0;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 15px;
    text-decoration: none;
    color: var(--text-primary);
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.btn-icon {
    font-size: 2rem;
}

.btn-label {
    display: block;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.btn-platform {
    display: block;
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* 平台选择器样式 */
.platform-selector {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    justify-content: center;
}

.platform-tab {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    background: white;
    color: var(--text-secondary);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

.platform-tab:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.platform-tab.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
    transform: translateY(-2px);
}

.platform-tab i {
    font-size: 1.2rem;
}

.selected-platform {
    background: var(--bg-secondary);
    border-radius: 15px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border: 2px solid var(--border-color);
    transition: all 0.3s ease;
}

.selected-platform.android {
    border-color: #4CAF50;
    background: linear-gradient(135deg, #4CAF50 0%, #45a049 100%);
    color: white;
}

.selected-platform.ios {
    border-color: #007aff;
    background: linear-gradient(135deg, #007aff 0%, #0056b3 100%);
    color: white;
}

.platform-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.platform-icon {
    font-size: 2rem;
    opacity: 0.9;
}

.platform-details {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.platform-name {
    font-size: 1.2rem;
    font-weight: 700;
}

.platform-version {
    font-size: 0.9rem;
    opacity: 0.8;
}

.download-action-btn {
    width: 100%;
    padding: 1rem 2rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.download-action-btn:hover {
    background: #5a67d8;
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(102, 126, 234, 0.4);
}

.download-action-btn:active {
    transform: translateY(0);
}

.android .btn-icon {
    color: #3ddc84;
}

.ios .btn-icon {
    color: #007aff;
}

.qr-code {
    display: flex;
    justify-content: center;
}

.qr-container {
    width: 180px;
    height: 200px;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 15px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-sm);
    padding: 1rem;
}

.qr-code-display {
    width: 120px;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 0.5rem;
}

.qr-code-display canvas {
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.qr-text {
    text-align: center;
    color: var(--text-secondary);
}

.qr-text p {
    margin: 0;
    font-size: 0.9rem;
    font-weight: 500;
}

.qr-subtitle {
    font-size: 0.75rem !important;
    color: var(--text-light) !important;
    margin-top: 0.25rem !important;
}

/* 版本选择器 */
.version-selector {
    margin-top: 1rem;
    padding: 1.5rem;
    background: white;
    border-radius: 15px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.version-selector h4 {
    margin-bottom: 1rem;
    color: var(--text-primary);
    font-size: 1.2rem;
}

.version-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.version-tab {
    padding: 0.75rem 1.5rem;
    border: 2px solid var(--border-color);
    background: white;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
    color: var(--text-secondary);
}

.version-tab:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.version-tab.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.version-info {
    min-height: 120px;
}

.version-details {
    animation: fadeIn 0.3s ease;
}

.version-details h5 {
    margin-bottom: 0.75rem;
    color: var(--text-primary);
    font-size: 1.1rem;
}

.version-details p {
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 联系我们 */
.contact {
    padding: 6rem 0;
    background: var(--bg-secondary);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background: white;
    border-radius: 15px;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
}

.contact-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.contact-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: white;
    flex-shrink: 0;
}

.contact-details h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.contact-details p {
    color: var(--text-secondary);
}

.contact-form {
    background: white;
    padding: 2.5rem;
    border-radius: 20px;
    box-shadow: var(--shadow-sm);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* 页脚 */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: white;
}

.footer-section p {
    color: #9ca3af;
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: #9ca3af;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: white;
}

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

.social-links a {
    width: 40px;
    height: 40px;
    background: var(--primary-color);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 1rem;
    text-align: center;
    color: #9ca3af;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: var(--shadow-lg);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }

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

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

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

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

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

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

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .nav-logo {
        gap: 0.5rem;
    }
    
    .logo-img {
        height: 35px;
    }
    
    .nav-logo h2 {
        font-size: 1.3rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

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

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

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

    .phone-mockup {
        width: 250px;
        height: 500px;
    }
    
    .chat-header {
        padding: 0.75rem;
    }
    
    .avatar {
        width: 35px;
        height: 35px;
        font-size: 0.7rem;
    }
    
    .user-details .name {
        font-size: 0.8rem;
    }
    
    .user-details .title {
        font-size: 0.7rem;
    }
    
    .price-tag {
        font-size: 0.7rem;
        padding: 0.3rem 0.6rem;
    }
    
    .chat-content {
        padding: 0.75rem;
    }
    
    .chat-bubble {
        font-size: 0.8rem;
        padding: 0.6rem 0.8rem;
    }
    
    .input-area {
        padding: 0.75rem;
    }
    
    .voice-btn, .send-btn {
        width: 32px;
        height: 32px;
    }
    
    .input-field input {
        font-size: 0.8rem;
        padding: 0.6rem 0.8rem;
    }
    
    .qr-container {
        width: 160px;
        height: 180px;
        padding: 0.75rem;
    }
    
    .qr-code-display {
        width: 100px;
        height: 100px;
    }
    
    .qr-text p {
        font-size: 0.8rem;
    }
    
    .qr-subtitle {
        font-size: 0.7rem !important;
    }

    .btn {
        padding: 0.8rem 1.5rem;
        font-size: 0.9rem;
    }

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

/* 滚动动画 */
@media (prefers-reduced-motion: no-preference) {
    .feature-card,
    .contact-item,
    .download-btn {
        opacity: 0;
        transform: translateY(30px);
        animation: fadeInUp 0.6s ease forwards;
    }

    .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:nth-child(7) { animation-delay: 0.7s; }
    .feature-card:nth-child(8) { animation-delay: 0.8s; }
    .feature-card:nth-child(9) { animation-delay: 0.9s; }
}

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