/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Source Han Sans SC', 'Noto Sans SC', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei UI', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    font-weight: 300;
    line-height: 1.6;
    color: #5d4037;
    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 rgba(0, 0, 0, 0.1);
    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;
    background-color: white;
}

.nav-logo {
    display: flex;
    align-items: center;
    font-size: 24px;
    font-weight: 300;
    color: #8d6e63;
}

.nav-logo .logo-img {
    height: 2.5rem;
    width: auto;
    margin-right: 0.5rem;
}

.nav-menu {
    display: flex;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: #5d4037;
    font-weight: 300;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: #8d6e63;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #8d6e63;
    transition: width 0.3s ease;
}

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

/* 主横幅区域 */
.hero {
    min-height: 100vh;
    background: linear-gradient(135deg, #8d6e63 0%, #5d4037 100%);
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="50" cy="50" r="1" fill="%23ffffff" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>') repeat;
    opacity: 0.3;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    color: white;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 300;
    line-height: 1.2;
    margin-bottom: 20px;
}

.gradient-text {
    color: white;
}

.hero-subtitle {
    font-size: 1.25rem;
    font-weight: 300;
    margin-bottom: 40px;
    opacity: 0.9;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    margin-bottom: 60px;
}

.btn-primary, .btn-secondary {
    padding: 15px 30px;
    border: none;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 10px;
}

.btn-primary {
    background: linear-gradient(45deg, #8d6e63, #5d4037);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(141, 110, 99, 0.4);
    background: linear-gradient(45deg, #a1887f, #6d4c41);
}

.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: white;
    font-weight: 500;
    font-size: 1.1rem;
    padding: 12px 24px;
    background: rgba(212, 165, 116, 0.2);
    border-radius: 25px;
    border: 1px solid white;
    position: relative;
    overflow: hidden;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.3s ease;
}

.btn-secondary:hover {
    background: rgba(212, 165, 116, 0.3);
    border-color: rgba(255, 255, 255, 0.8);
    transform: translateY(-1px);
}

.coming-soon-text {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: white;
    font-weight: 500;
    font-size: 1.1rem;
    padding: 12px 24px;
    background: rgba(212, 165, 116, 0.2);
    border-radius: 25px;
    border: 1px solid white;
    position: relative;
    overflow: hidden;
}

.coming-soon-text::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(212, 165, 116, 0.4), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { left: -100%; }
    100% { left: 100%; }
}

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

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

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 300;
    color: #8d6e63;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* 手机模型 */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.phone-mockup {
    width: 300px;
    height: 600px;
    background: #5d4037;
    border-radius: 30px;
    padding: 20px;
    box-shadow: 0 20px 60px rgba(93, 64, 55, 0.3);
    position: relative;
    animation: float 6s ease-in-out infinite;
    border: 3px solid white;
}

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

.phone-screen {
    width: 100%;
    height: 100%;
    background: #f8fafc;
    border-radius: 20px;
    overflow: hidden;
}

.app-interface {
    padding: 20px;
    height: 100%;
}

.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid #e2e8f0;
}

.app-header h3 {
    font-size: 18px;
    color: #1e293b;
}

.app-header i {
    color: #ef4444;
    font-size: 20px;
}

.topic-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.topic-item {
    background: white;
    padding: 15px;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    border-left: 4px solid #e2e8f0;
    transition: all 0.3s ease;
}

.topic-item.hot {
    border-left-color: #ef4444;
    background: linear-gradient(135deg, #fef2f2, #ffffff);
}

.topic-title {
    font-size: 14px;
    font-weight: 600;
    color: #1e293b;
    margin-bottom: 8px;
}

.topic-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
}

.status {
    padding: 2px 8px;
    border-radius: 12px;
    font-weight: 500;
}

.status.ongoing {
    background: #fef3c7;
    color: #92400e;
}

.status.completed {
    background: #d1fae5;
    color: #065f46;
}

.engagement {
    color: #64748b;
}

/* 功能特色区域 */
.features.about {
    padding: 100px 0;
    background: #f5f5f5;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 300;
    color: #5d4037;
    margin-bottom: 15px;
}

.section-header p {
    font-size: 1.2rem;
    color: #64748b;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.feature-card {
    background: white;
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.feature-card:nth-child(1) .feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #3e2723, #5d4037);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    color: white;
    font-size: 32px;
}

.feature-card:nth-child(2) .feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #5d4037, #8d6e63);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    color: white;
    font-size: 32px;
}

.feature-card:nth-child(3) .feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #8d6e63, #a1887f);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    color: white;
    font-size: 32px;
}

.feature-card:nth-child(4) .feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #6d4c41, #8d6e63);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    color: white;
    font-size: 32px;
}

.feature-card:nth-child(5) .feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #4e342e, #6d4c41);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    color: white;
    font-size: 32px;
}

.feature-card:nth-child(6) .feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #795548, #a1887f);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    color: white;
    font-size: 32px;
}

.feature-card h3 {
    font-size: 1.5rem;
    font-weight: 300;
    color: #5d4037;
    margin-bottom: 15px;
}

.feature-card p {
    color: #64748b;
    line-height: 1.6;
}

/* 产品演示区域 */
.demo {
    padding: 100px 0;
    background: white;
}

.demo-content {
    max-width: 1000px;
    margin: 0 auto;
}

.demo-tabs {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 40px;
    background: #f5f5f5;
    border-radius: 10px;
    padding: 5px;
}

.tab-btn {
    padding: 12px 30px;
    border: 2px solid #efebe9;
    background: white;
    border-radius: 50px;
    font-weight: 300;
    cursor: pointer;
    transition: all 0.3s ease;
    color: #8d6e63;
}

.tab-btn.active {
    background: #8d6e63;
    border-color: #8d6e63;
    color: white;
}

.tab-btn:hover:not(.active) {
    border-color: #8d6e63;
    color: #8d6e63;
}

.demo-panels {
    position: relative;
}

.demo-panel {
    display: none;
    animation: fadeIn 0.5s ease;
}

.demo-panel.active {
    display: block;
}

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

.demo-interface {
    background: #f8fafc;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.interface-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid #e2e8f0;
}

.interface-header h3 {
    font-size: 1.5rem;
    color: #1e293b;
}

.sort-options {
    display: flex;
    gap: 10px;
}

.sort-btn {
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.sort-btn.active {
    background: linear-gradient(45deg, #5d4037, #8d6e63);
    color: white;
    box-shadow: 0 2px 8px rgba(93, 64, 55, 0.3);
}

.sort-btn:not(.active) {
    background: #e2e8f0;
    color: #64748b;
}

.topic-cards {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.topic-card {
    background: white;
    padding: 25px;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    border: 1px solid #e2e8f0;
}

.topic-card.trending {
    border-left: 4px solid #ef4444;
    background: linear-gradient(135deg, #fef2f2, #ffffff);
}

.topic-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.topic-header h4 {
    font-size: 1.2rem;
    color: #1e293b;
}

.status-badge {
    padding: 4px 12px;
    border-radius: 15px;
    font-size: 12px;
    font-weight: 600;
}

.status-badge.ongoing {
    background: #fef3c7;
    color: #92400e;
}

.status-badge.completed {
    background: #d1fae5;
    color: #065f46;
}

.topic-stats {
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
    font-size: 14px;
    color: #64748b;
}

.topic-stats span {
    display: flex;
    align-items: center;
    gap: 5px;
}

.topic-timeline {
    border-left: 2px solid #e2e8f0;
    padding-left: 20px;
}

.timeline-item {
    display: flex;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid #f1f5f9;
}

.timeline-item:last-child {
    border-bottom: none;
}

.time {
    font-size: 12px;
    color: #94a3b8;
    min-width: 80px;
}

.event {
    font-size: 14px;
    color: #475569;
}

.update-count {
    background: #ef4444;
    color: white;
    padding: 4px 12px;
    border-radius: 15px;
    font-size: 12px;
    font-weight: 600;
}

.following-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.following-item {
    background: white;
    padding: 20px;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
}

.following-item.updated {
    border-left: 4px solid #10b981;
    background: linear-gradient(135deg, #f0fdf4, #ffffff);
}

.item-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.item-header h4 {
    color: #1e293b;
}

.update-badge {
    background: #10b981;
    color: white;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 10px;
    font-weight: 600;
}

.latest-update {
    color: #475569;
    margin-bottom: 8px;
}

.update-time {
    font-size: 12px;
    color: #94a3b8;
}

.create-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-group label {
    font-weight: 600;
    color: #374151;
}

.form-group input,
.form-group select {
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 10px;
    font-size: 14px;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #2563eb;
}

.status-selector {
    display: flex;
    gap: 10px;
}

.status-option {
    padding: 10px 20px;
    border: 2px solid #e2e8f0;
    background: white;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.status-option.active {
    background: #2563eb;
    border-color: #2563eb;
    color: white;
}

/* 关于我们区域 */
.about {
    padding: 100px 0;
    background: #efebe9;
    color: #5d4037;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-text h2 {
    font-size: 2.5rem;
    font-weight: 300;
    margin-bottom: 30px;
}

.about-text p {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 20px;
    opacity: 0.9;
}

.about-features {
    display: flex;
    gap: 30px;
    margin-top: 40px;
}

.about-feature {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 10px;
}

.about-feature:nth-child(1) i {
    font-size: 2rem;
    color: #3e2723;
}

.about-feature:nth-child(2) i {
    font-size: 2rem;
    color: #5d4037;
}

.about-feature:nth-child(3) i {
    font-size: 2rem;
    color: #8d6e63;
}

.about-feature span {
    font-weight: 600;
}

.about-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.visual-element {
    position: relative;
    width: 400px;
    height: 400px;
    overflow: visible;
    animation: containerFloat 12s ease-in-out infinite;
}

.floating-card {
    position: absolute;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    padding: 20px;
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    animation: floatCard 6s ease-in-out infinite;
}

.floating-card:nth-child(1) {
    top: 20%;
    left: 10%;
    animation: floatCard 13s linear infinite;
    animation-delay: 0s;
}

.floating-card:nth-child(2) {
    top: 60%;
    right: 15%;
    animation: floatCard2 17s ease-in-out infinite;
    animation-delay: 3.7s;
}

.floating-card:nth-child(3) {
    bottom: 30%;
    left: 40%;
    animation: floatCard3 23s cubic-bezier(0.4, 0, 0.6, 1) infinite;
    animation-delay: 8.3s;
}

@keyframes floatCard {
    0% { transform: translate(0px, 0px) rotate(0deg); }
    8% { transform: translate(35px, -25px) rotate(4deg); }
    16% { transform: translate(50px, 15px) rotate(-3deg); }
    24% { transform: translate(25px, 45px) rotate(6deg); }
    32% { transform: translate(-15px, 55px) rotate(-4deg); }
    40% { transform: translate(-45px, 30px) rotate(7deg); }
    48% { transform: translate(-60px, -5px) rotate(-5deg); }
    56% { transform: translate(-35px, -40px) rotate(3deg); }
    64% { transform: translate(-5px, -60px) rotate(-6deg); }
    72% { transform: translate(25px, -50px) rotate(4deg); }
    80% { transform: translate(45px, -25px) rotate(-2deg); }
    88% { transform: translate(35px, 5px) rotate(2deg); }
    96% { transform: translate(15px, -10px) rotate(-1deg); }
    100% { transform: translate(0px, 0px) rotate(0deg); }
}

@keyframes floatCard2 {
    0% { transform: translate(0px, 0px) rotate(0deg); }
    7% { transform: translate(-20px, -45px) rotate(-5deg); }
    14% { transform: translate(15px, -60px) rotate(7deg); }
    21% { transform: translate(50px, -35px) rotate(-4deg); }
    28% { transform: translate(65px, 10px) rotate(6deg); }
    35% { transform: translate(40px, 50px) rotate(-3deg); }
    42% { transform: translate(5px, 70px) rotate(5deg); }
    49% { transform: translate(-30px, 55px) rotate(-7deg); }
    56% { transform: translate(-55px, 25px) rotate(4deg); }
    63% { transform: translate(-70px, -15px) rotate(-6deg); }
    70% { transform: translate(-45px, -50px) rotate(3deg); }
    77% { transform: translate(-10px, -65px) rotate(-4deg); }
    84% { transform: translate(25px, -55px) rotate(5deg); }
    91% { transform: translate(40px, -30px) rotate(-2deg); }
    98% { transform: translate(20px, -10px) rotate(1deg); }
    100% { transform: translate(0px, 0px) rotate(0deg); }
}

@keyframes floatCard3 {
    0% { transform: translate(0px, 0px) rotate(0deg); }
    6% { transform: translate(18px, -30px) rotate(3deg); }
    12% { transform: translate(-8px, -55px) rotate(-4deg); }
    18% { transform: translate(-35px, -40px) rotate(6deg); }
    24% { transform: translate(-60px, -10px) rotate(-5deg); }
    30% { transform: translate(-70px, 25px) rotate(7deg); }
    36% { transform: translate(-50px, 55px) rotate(-6deg); }
    42% { transform: translate(-20px, 75px) rotate(4deg); }
    48% { transform: translate(15px, 65px) rotate(-3deg); }
    54% { transform: translate(45px, 40px) rotate(5deg); }
    60% { transform: translate(65px, 10px) rotate(-7deg); }
    66% { transform: translate(55px, -25px) rotate(6deg); }
    72% { transform: translate(30px, -50px) rotate(-4deg); }
    78% { transform: translate(5px, -65px) rotate(3deg); }
    84% { transform: translate(-20px, -55px) rotate(-2deg); }
    90% { transform: translate(-10px, -30px) rotate(4deg); }
    96% { transform: translate(10px, -15px) rotate(-1deg); }
    100% { transform: translate(0px, 0px) rotate(0deg); }
}

@keyframes containerFloat {
    0% { transform: translateY(0px) rotate(0deg); }
    25% { transform: translateY(-20px) rotate(1deg); }
    50% { transform: translateY(-35px) rotate(-1.5deg); }
    75% { transform: translateY(-15px) rotate(0.8deg); }
    100% { transform: translateY(0px) rotate(0deg); }
}

.floating-card:nth-child(1) i {
    font-size: 1.5rem;
    color: #6d4c41;
}

.floating-card:nth-child(2) i {
    font-size: 1.5rem;
    color: #8d6e63;
}

.floating-card:nth-child(3) i {
    font-size: 1.5rem;
    color: #a1887f;
}

.floating-card span {
    font-size: 0.9rem;
    font-weight: 600;
}

/* 页脚 */
.footer {
    background: #3e2723;
    color: white;
    padding: 60px 0 20px;
}

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

.footer-logo {
    display: flex;
    align-items: center;
    font-size: 24px;
    font-weight: 300;
    color: #d7ccc8;
    margin-bottom: 15px;
}

.footer-logo i {
    margin-right: 10px;
}

.footer-section h4 {
    margin-bottom: 20px;
    color: #d7ccc8;
    font-weight: 300;
}

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

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #bcaaa4;
    text-decoration: none;
    transition: color 0.3s ease;
    font-weight: 300;
}

.footer-section ul li a:hover {
    color: #d7ccc8;
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: rgba(255, 215, 0, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ffd700;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: #ffd700;
    color: #1e293b;
    transform: translateY(-2px);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #5d4037;
    color: #bcaaa4;
    font-weight: 300;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .phone-mockup {
        width: 250px;
        height: 500px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .demo-tabs {
        flex-wrap: wrap;
    }
    
    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .about-features {
        justify-content: center;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .topic-stats {
        flex-wrap: wrap;
    }
    
    .timeline-item {
        flex-direction: column;
        gap: 5px;
    }
    
    .modal-content {
        margin: 20% auto;
        width: 95%;
    }
    
    .input-group {
        flex-direction: column;
    }
    
    .input-group button {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-header h2 {
        font-size: 2rem;
    }
    
    .phone-mockup {
        width: 200px;
        height: 400px;
    }
    
    .demo-interface {
        padding: 20px;
    }
    
    .topic-card {
        padding: 15px;
    }
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f5f9;
}

::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}

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

/* 新闻项目样式 */
.news-title {
    font-size: 1.1rem;
    font-weight: 300;
    color: #5d4037;
    margin-bottom: 8px;
}

.news-meta {
    font-size: 0.9rem;
    color: #8d6e63;
    display: flex;
    align-items: center;
    gap: 15px;
    font-weight: 300;
}

.topic-tag {
    background: linear-gradient(45deg, #8d6e63, #5d4037);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 300;
    border: 1px solid white;
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: #8d6e63;
    color: white;
    border: 2px solid white;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    transition: all 0.3s ease;
    z-index: 1000;
    box-shadow: 0 4px 15px rgba(141, 110, 99, 0.3);
}

.back-to-top:hover {
    background: #6d4c41;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(141, 110, 99, 0.4);
}

/* 对话框样式 */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
    animation: fadeIn 0.3s ease-out;
}

.modal-content {
    background-color: #fff;
    margin: 10% auto;
    padding: 0;
    border-radius: 12px;
    width: 90%;
    max-width: 450px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    animation: slideIn 0.3s ease-out;
    overflow: hidden;
}

.modal-content.success {
    text-align: center;
}

.modal-header {
    background: linear-gradient(135deg, #8B4513 0%, #A0522D 100%);
    color: white;
    padding: 20px;
    position: relative;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    margin: 0;
    font-size: 1.3rem;
    font-weight: 600;
}

.close {
    color: rgba(255, 255, 255, 0.8);
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
    line-height: 1;
}

.close:hover {
    color: white;
}

.modal-body {
    padding: 25px;
}

.modal-body p {
    margin: 0 0 20px 0;
    color: #666;
    line-height: 1.6;
}

.input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

.input-group input {
    flex: 1;
    padding: 12px 15px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
    outline: none;
}

.input-group input:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.input-group button {
    padding: 12px 20px;
    background: linear-gradient(135deg, #8B4513 0%, #A0522D 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.3s ease;
    min-width: 80px;
}

.input-group button:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(139, 69, 19, 0.4);
}

.input-group button:active {
    transform: translateY(0);
}

.input-group button:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

.error-message {
    color: #e74c3c;
    font-size: 14px;
    margin-top: 5px;
    min-height: 20px;
}

.success-icon {
    font-size: 4rem;
    color: #27ae60;
    margin-bottom: 20px;
}

.success-icon i {
    animation: bounceIn 0.6s ease-out;
}

.btn-primary {
    background: linear-gradient(135deg, #27ae60 0%, #2ecc71 100%);
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.3s ease;
    margin-top: 10px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(39, 174, 96, 0.4);
}

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

/* 动画效果 */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-50px) scale(0.9);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

@keyframes bounceIn {
    0% {
        opacity: 0;
        transform: scale(0.3);
    }
    50% {
        opacity: 1;
        transform: scale(1.1);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}