/* 全局样式 */
:root {
    --primary-color: #00d173; /* 绿色主题色 */
    --secondary-color: #00a35c; /* 稍深的绿色 */
    --accent-color: #ff4d4d;
    --text-color: #333333; /* 深灰色文字 */
    --light-text: #666666; /* 中灰色文字 */
    --bg-color: #f8f9fa; /* 浅灰白色背景 */
    --light-bg: #ffffff; /* 白色背景 */
    --border-color: #dee2e6; /* 浅灰色边框 */
    --success-color: #00d173;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1); /* 更浅的阴影 */
}

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

body {
    font-family: 'PingFang SC', 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background-color: var(--bg-color);
    background-image: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: color 0.3s ease;
}

a:hover {
    color: var(--secondary-color);
}

ul {
    list-style: none;
}

.hidden {
    display: none;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 4px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    font-size: 16px;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white; /* 白色文字 */
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    background-color: var(--secondary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 209, 115, 0.3);
}

.btn-outline {
    background-color: transparent;
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
}

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

.btn-large {
    padding: 14px 28px;
    font-size: 18px;
}

.btn-small {
    padding: 6px 12px;
    font-size: 14px;
}

/* 头部导航 */
header {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border-color);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
}

.logo a {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
}

nav ul {
    display: flex;
}

nav ul li {
    margin-left: 30px;
}

nav ul li a {
    color: var(--text-color);
    font-weight: 500;
    font-size: 18px;
}

nav ul li a.active,
nav ul li a:hover {
    color: var(--primary-color);
    font-size: 18px; /* 增加字体大小 */
    font-weight: 600; /* 加粗字体 */
    transform: scale(1.05); /* 轻微放大效果 */
    transition: all 0.2s ease; /* 平滑过渡效果 */
}

.auth-buttons {
    display: flex;
    gap: 10px;
}

/* 英雄区域 */
.hero {
    background: linear-gradient(135deg, #00d173, #00a35c);
    color: white;
    padding: 80px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 30%, rgba(255, 255, 255, 0.1) 0%, transparent 40%),
        radial-gradient(circle at 80% 70%, rgba(255, 255, 255, 0.1) 0%, transparent 40%);
    z-index: 1;
}

.hero .container {
    position: relative;
    z-index: 2;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 42px;
    margin-bottom: 20px;
}

.hero p {
    font-size: 20px;
    margin-bottom: 40px;
    opacity: 0.9;
}

.url-shortener {
    /* display: flex;
    max-width: 600px; */
    margin: 0 auto;
    /* box-shadow: var(--shadow); */
    border-radius: 4px;
    overflow: hidden;
}

.url-shortener input,
.url-shortener select {
    flex: 1;
    padding: 15px 20px;
    border: none;
    font-size: 16px;
    height: 50px; /* 确保统一高度 */
}

.url-shortener select {
    background-color: white;
    cursor: pointer;
}

.url-shortener button {
    border-radius: 0;
    padding: 15px 25px;
}

/* 结果容器 */
.result-container {
    background-color: white;
    border-radius: 8px;
    padding: 20px;
    margin-top: 20px;
    box-shadow: var(--shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.result-container.hidden {
    display: none !important;
}

.short-url-container {
    display: flex;
    flex: 1;
    margin-right: 20px;
}

.short-url-container input {
    flex: 1;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px 0 0 4px;
    font-size: 16px;
}

.short-url-container button {
    border-radius: 0 4px 4px 0;
}

.qr-code {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.qr-code img {
    width: 100px;
    height: 100px;
    margin-bottom: 10px;
}

/* 特性部分 */
.features {
    padding: 80px 0;
    background-color: var(--light-bg);
}

.features h2 {
    text-align: center;
    margin-bottom: 50px;
    font-size: 32px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.feature-card {
    background-color: var(--bg-color);
    border-radius: 8px;
    padding: 30px;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 36px;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.feature-card h3 {
    margin-bottom: 15px;
    font-size: 20px;
}

.features-more {
    text-align: center;
    margin-top: 40px;
}

.features-more .btn {
    transition: all 0.3s ease;
    font-weight: 600;
}

.features-more .btn i {
    margin-right: 8px;
}

.features-more .btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

/* 统计部分 */
.stats {
    padding: 60px 0;
    background-color: var(--primary-color);
    color: white;
}

.stats .container {
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
    text-align: center;
}

.stat-item {
    padding: 20px;
}

.stat-item h3 {
    font-size: 36px;
    margin-bottom: 10px;
}

/* CTA部分 */
.cta {
    padding: 80px 0;
    text-align: center;
    background-color: var(--light-bg);
}

.cta h2 {
    font-size: 32px;
    margin-bottom: 20px;
}

.cta p {
    font-size: 18px;
    margin-bottom: 30px;
    color: var(--light-text);
}

/* 页脚 */
footer {
    background-color: #2c3e50;
    color: white;
    padding: 60px 0 20px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h4 {
    font-size: 18px;
    margin-bottom: 20px;
    position: relative;
}

.footer-col h4::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -8px;
    width: 40px;
    height: 2px;
    background-color: var(--primary-color);
}

.footer-col p {
    margin-bottom: 20px;
    opacity: 0.8;
}

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

.footer-col ul li a {
    color: rgba(255, 255, 255, 0.8);
}

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

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

.social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background-color: var(--primary-color);
    transform: translateY(-3px);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    opacity: 0.7;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
    }
    
    nav ul {
        margin: 20px 0;
    }
    
    nav ul li {
        margin: 0 10px;
    }
    
    .url-shortener {
        flex-direction: column;
    }
    
    .url-shortener input,
    .url-shortener button {
        width: 100%;
        border-radius: 4px;
    }
    
    .url-shortener button {
        margin-top: 10px;
    }
    
    .result-container {
        flex-direction: column;
    }
    
    .short-url-container {
        width: 100%;
        margin-right: 0;
        margin-bottom: 20px;
    }
}

@media (max-width: 576px) {
    .hero h1 {
        font-size: 32px;
    }
    
    .hero p {
        font-size: 18px;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
}