/* CSS变量 */
:root {
    --primary-color: #007AFF;
    --primary-dark: #0056CC;
    --secondary-color: #5856D6;
    --success-color: #34C759;
    --warning-color: #FF9500;
    --error-color: #FF3B30;
    --text-primary: #1D1D1F;
    --text-secondary: #6E6E73;
    --background: #FFFFFF;
    --surface: #F2F2F7;
    --border: #D1D1D6;
    --shadow: rgba(0, 0, 0, 0.1);
    --gradient-primary: linear-gradient(135deg, #007AFF 0%, #5856D6 100%);
    --gradient-success: linear-gradient(135deg, #34C759 0%, #30D158 100%);
    --border-radius: 12px;
    --container-max-width: 1200px;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

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

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

.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
}

.nav-brand i {
    color: var(--primary-color);
    font-size: 24px;
}

.nav-menu {
    display: flex;
    gap: 32px;
}

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

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width 0.3s ease;
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: all 0.3s ease;
}

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

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 24px;
}

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

.hero-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 60px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 16px 24px;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 16px rgba(0, 122, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 122, 255, 0.4);
}

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

.btn-secondary:hover {
    background: white;
    transform: translateY(-2px);
    box-shadow: 0 8px 24px var(--shadow);
}

.hero-stats {
    display: flex;
    gap: 40px;
}

.stat {
    text-align: center;
}

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

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

/* 手机预览 */
.phone-mockup {
    position: relative;
    width: 300px;
    height: 600px;
    background: linear-gradient(145deg, #1c1c1e, #2c2c2e);
    border-radius: 40px;
    padding: 8px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    margin: 0 auto;
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: white;
    border-radius: 32px;
    overflow: hidden;
    position: relative;
}

.app-preview {
    padding: 16px;
    height: 100%;
}

.status-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    font-size: 14px;
    font-weight: 600;
}

.app-header {
    text-align: center;
    padding: 20px 0;
}

.app-header h3 {
    margin-bottom: 12px;
    color: var(--text-secondary);
}

.balance {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.quick-stats {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 30px;
}

.stat-card {
    background: var(--surface);
    border-radius: 12px;
    padding: 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.stat-card.income span:last-child {
    color: var(--success-color);
    font-weight: 600;
}

.stat-card.expense span:last-child {
    color: var(--error-color);
    font-weight: 600;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(0, 122, 255, 0.05) 0%, rgba(88, 86, 214, 0.05) 100%);
    z-index: -1;
}

/* 功能特性 */
.features {
    padding: 120px 0;
    background: var(--surface);
}

.section-header {
    text-align: center;
    margin-bottom: 80px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
}

.feature-card {
    background: white;
    padding: 40px 32px;
    border-radius: var(--border-radius);
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid var(--border);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px var(--shadow);
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient-primary);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
}

.feature-icon i {
    font-size: 32px;
    color: white;
}

.feature-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 16px;
}

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

/* 技术亮点 */
.tech-highlights {
    padding: 120px 0;
}

.tech-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.tech-text h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 40px;
}

.tech-features {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.tech-feature {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.tech-feature i {
    font-size: 24px;
    color: var(--primary-color);
    margin-top: 4px;
    flex-shrink: 0;
}

.tech-feature h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 8px;
}

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

.code-preview {
    background: #1d1d1f;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 20px 40px var(--shadow);
}

.code-header {
    background: #2c2c2e;
    padding: 12px 16px;
    display: flex;
    gap: 8px;
    align-items: center;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ff5f57; }
.dot.yellow { background: #ffbd2e; }
.dot.green { background: #28ca42; }

.code-content {
    padding: 24px;
    font-family: 'Monaco', 'Menlo', monospace;
    font-size: 14px;
    line-height: 1.5;
    color: #ffffff;
    overflow-x: auto;
}

.code-content pre {
    margin: 0;
}

/* 下载区域 */
.download {
    padding: 120px 0;
    background: var(--gradient-primary);
    color: white;
    text-align: center;
}

.download-content h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.download-content p {
    font-size: 1.25rem;
    margin-bottom: 40px;
    opacity: 0.9;
}

.download-buttons {
    margin-bottom: 40px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 16px;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius);
    padding: 16px 24px;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

.download-btn:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-2px);
}

.download-btn i {
    font-size: 32px;
}

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

.download-btn span {
    display: block;
    font-size: 12px;
    opacity: 0.8;
}

.download-btn strong {
    font-size: 16px;
    font-weight: 600;
}

.download-info {
    display: flex;
    justify-content: center;
    gap: 40px;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 8px;
    opacity: 0.9;
}

/* 页脚 */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 80px 0 40px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 80px;
    margin-bottom: 40px;
}

.footer-brand .brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 16px;
}

.footer-brand i {
    color: var(--primary-color);
    font-size: 24px;
}

.footer-brand p {
    opacity: 0.8;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.link-group h4 {
    margin-bottom: 20px;
    font-weight: 600;
}

.link-group a {
    display: block;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    margin-bottom: 12px;
    transition: color 0.3s ease;
}

.link-group a:hover {
    color: white;
}

.footer-bottom {
    padding-top: 40px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    opacity: 0.6;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }

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

    .nav-toggle {
        display: flex;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }

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

    .phone-mockup {
        width: 250px;
        height: 500px;
    }

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

    .tech-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-stats {
        justify-content: center;
        gap: 24px;
    }

    .download-info {
        flex-direction: column;
        gap: 16px;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .footer-links {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .hero {
        padding: 100px 0 60px;
    }

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

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

    .features,
    .tech-highlights,
    .download {
        padding: 80px 0;
    }
}

/* 动画效果 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-text > * {
    animation: fadeInUp 0.8s ease forwards;
}

.hero-title { animation-delay: 0.1s; }
.hero-description { animation-delay: 0.2s; }
.hero-buttons { animation-delay: 0.3s; }
.hero-stats { animation-delay: 0.4s; }

.phone-mockup {
    animation: fadeInUp 0.8s ease 0.5s forwards;
    opacity: 0;
}

/* 滚动动画 */
.feature-card,
.tech-feature {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.feature-card.animate,
.tech-feature.animate {
    opacity: 1;
    transform: translateY(0);
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 模态框样式 */
.modal {
    display: none;
    position: fixed;
    z-index: 10000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(10px);
    animation: fadeIn 0.3s ease;
}

.modal.show {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: white;
    border-radius: var(--border-radius);
    width: 90%;
    max-width: 800px;
    max-height: 80vh;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: slideUp 0.3s ease;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 24px 32px;
    border-bottom: 1px solid var(--border);
    background: var(--surface);
}

.modal-header h2 {
    margin: 0;
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 600;
}

.modal-close {
    font-size: 28px;
    font-weight: 300;
    color: var(--text-secondary);
    cursor: pointer;
    transition: color 0.3s ease;
    line-height: 1;
    padding: 4px;
}

.modal-close:hover {
    color: var(--text-primary);
}

.modal-body {
    padding: 32px;
    overflow-y: auto;
    max-height: calc(80vh - 100px);
    line-height: 1.7;
}

.modal-body h3 {
    color: var(--text-primary);
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 16px;
    margin-top: 24px;
}

.modal-body h3:first-child {
    margin-top: 0;
}

.modal-body p {
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.modal-body ul {
    color: var(--text-secondary);
    margin-bottom: 16px;
    padding-left: 20px;
}

.modal-body li {
    margin-bottom: 8px;
}

.modal-body strong {
    color: var(--text-primary);
}

.contact-info {
    background: var(--surface);
    border-radius: var(--border-radius);
    padding: 24px;
    margin: 20px 0;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.contact-item:last-child {
    margin-bottom: 0;
}

.contact-item i {
    color: var(--primary-color);
    font-size: 18px;
    width: 20px;
}

.feedback-form {
    background: var(--surface);
    border-radius: var(--border-radius);
    padding: 24px;
    margin: 20px 0;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-family: inherit;
    font-size: 14px;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.form-submit {
    background: var(--gradient-primary);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.form-submit:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 122, 255, 0.3);
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

/* 模态框响应式设计 */
@media (max-width: 768px) {
    .modal-content {
        width: 95%;
        max-height: 90vh;
    }
    
    .modal-header {
        padding: 20px 24px;
    }
    
    .modal-header h2 {
        font-size: 1.25rem;
    }
    
    .modal-body {
        padding: 24px;
    }
    
    .contact-info,
    .feedback-form {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .modal-content {
        width: 100%;
        height: 100%;
        max-height: 100vh;
        border-radius: 0;
    }
    
    .modal-header {
        padding: 16px 20px;
    }
    
    .modal-body {
        padding: 20px;
        max-height: calc(100vh - 80px);
    }
}