:root {
    --primary-color: #1e293b;
    --secondary-color: #3b82f6;
    --accent-color: #f59e0b;
    --background-color: #f1f5f9;
    --card-background: #ffffff;
    --text-color: #334155;
    --text-light: #64748b;
    --highlight-color: #f59e0b;
    --border-color: #e2e8f0;
    --box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05);
    --nav-height: 68px;
    --transition-standard: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.tags-container {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin: 1.5rem 0 2rem;
}

.tag {
    display: inline-block;
    background-color: rgba(59, 130, 246, 0.08);
    color: var(--secondary-color);
    padding: 8px 16px;
    border-radius: 30px;
    font-size: 0.85rem;
    font-weight: 600;
    transition: var(--transition-standard);
    border: 1px solid rgba(59, 130, 246, 0.12);
    letter-spacing: 0.3px;
}

.tag:hover {
    background-color: var(--secondary-color);
    color: white;
    transform: translateY(-3px);
    box-shadow: 0 6px 12px rgba(59, 130, 246, 0.15);
}

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

body {
    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.7;
    color: var(--text-color);
    background-color: var(--background-color);
    padding-top: var(--nav-height);
    opacity: 0;
    animation: fadeInPage 0.8s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* 导航菜单样式 */
nav {
    background-color: rgba(30, 41, 59, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    height: var(--nav-height);
    display: flex;
    align-items: center;
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), background-color 0.3s ease;
}

nav:hover {
    background-color: rgba(30, 41, 59, 0.98);
}

nav .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

nav ul {
    display: flex;
    justify-content: center;
    list-style: none;
    transition: var(--transition-standard);
    margin: 0;
    padding: 0;
}

nav ul li {
    margin: 0 1.2rem;
    position: relative;
}

nav ul li a {
    color: rgba(255, 255, 255, 0.85);
    text-decoration: none;
    font-weight: 500;
    padding: 0.8rem 1.2rem;
    border-radius: 8px;
    transition: var(--transition-standard);
    position: relative;
    letter-spacing: 0.3px;
    display: inline-block;
}

nav ul li a::before {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 10%;
    width: 80%;
    height: 2px;
    background: linear-gradient(to right, var(--secondary-color), var(--accent-color));
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border-radius: 2px;
}

nav ul li a:hover {
    color: white;
    transform: translateY(-2px);
}

nav ul li a:hover::before {
    transform: scaleX(1);
    transform-origin: left;
}

nav ul li a.active {
    color: white;
    font-weight: 600;
}

nav ul li a.active::before {
    transform: scaleX(1);
    background: linear-gradient(to right, var(--accent-color), var(--secondary-color));
}

/* 品牌名称 */
.brand {
    display: flex;
    align-items: center;
    font-weight: 700;
    font-size: 1.4rem;
    color: white;
    text-decoration: none;
    letter-spacing: -0.5px;
}

.brand i {
    margin-right: 10px;
    color: var(--accent-color);
    font-size: 1.6rem;
}

/* 汉堡菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    cursor: pointer;
}

.menu-toggle span {
    height: 3px;
    width: 100%;
    background-color: white;
    border-radius: 3px;
    transition: var(--transition-standard);
}

main {
    padding: 3rem 0;
}

.content-section {
    background: var(--card-background);
    border-radius: 16px;
    padding: 3rem;
    margin-bottom: 3rem;
    box-shadow: var(--box-shadow);
    transition: var(--transition-standard);
    border: 1px solid var(--border-color);
    position: relative;
    z-index: 1;
    overflow: hidden;
}

.content-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.05) 0%, rgba(245, 158, 11, 0.05) 100%);
    z-index: -1;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.content-section:hover {
    transform: translateY(-6px);
    box-shadow: 0 20px 40px -10px rgba(0,0,0,0.1);
}

.content-section:hover::before {
    opacity: 1;
}

h1, h2, h3 {
    color: var(--primary-color);
    margin-bottom: 1.8rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    line-height: 1.3;
}

h1 {
    font-size: 2.75rem;
    line-height: 1.2;
}

h2 {
    font-size: 2rem;
    margin-top: 1.8rem;
}

h3 {
    font-size: 1.5rem;
    color: var(--secondary-color);
}

p {
    margin-bottom: 1.4rem;
    color: var(--text-color);
    font-size: 1.1rem;
}

.svg-container {
    width: 100%;
    max-width: 900px;
    margin: 3.5rem auto;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--box-shadow);
    transition: var(--transition-standard);
    border: 1px solid var(--border-color);
    background-color: white;
    position: relative;
}

.svg-container::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    box-shadow: inset 0 0 0 3px rgba(59, 130, 246, 0);
    border-radius: 16px;
    transition: box-shadow 0.3s ease;
}

.svg-container:hover {
    transform: scale(1.03);
    box-shadow: 0 25px 50px rgba(0,0,0,0.12);
}

.svg-container:hover::after {
    box-shadow: inset 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.phase-duration, .phase-role {
    color: var(--secondary-color);
    font-style: italic;
    margin-bottom: 1.2rem;
    font-size: 1.1rem;
}

ul {
    list-style-position: inside;
    margin-bottom: 1.8rem;
}

ul li {
    margin-bottom: 1rem;
    padding-left: 1.2rem;
    position: relative;
    list-style-type: none;
    transition: var(--transition-standard);
}

ul li::before {
    content: "•";
    color: var(--secondary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
    transition: var(--transition-standard);
}

ul li:hover {
    transform: translateX(5px);
}

ul li:hover::before {
    color: var(--accent-color);
}

.budget-section {
    border-left: 4px solid var(--secondary-color);
    padding: 2rem;
    margin-top: 2rem;
    background-color: rgba(59, 130, 246, 0.05);
    border-radius: 0 12px 12px 0;
    transition: var(--transition-standard);
}

.budget-section:hover {
    border-left-color: var(--accent-color);
    background-color: rgba(59, 130, 246, 0.08);
}

.highlight {
    color: var(--highlight-color);
    font-weight: 700;
}

.fade-in {
    animation: fadeIn 1s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes fadeIn {
    from { 
        opacity: 0; 
        transform: translateY(30px); 
        filter: blur(5px);
    }
    to { 
        opacity: 1; 
        transform: translateY(0);
        filter: blur(0); 
    }
}

.btn {
    display: inline-block;
    background-color: var(--secondary-color);
    color: white;
    padding: 1rem 2.5rem;
    border-radius: 10px;
    text-decoration: none;
    margin-top: 2rem;
    transition: var(--transition-standard);
    font-weight: 600;
    box-shadow: 0 8px 20px rgba(59, 130, 246, 0.25);
    position: relative;
    overflow: hidden;
    z-index: 1;
    letter-spacing: 0.5px;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 0;
    height: 100%;
    background-color: var(--accent-color);
    transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: -1;
}

.btn:hover {
    background-color: var(--secondary-color);
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 12px 25px rgba(59, 130, 246, 0.3);
    color: white;
}

.btn:active {
    transform: translateY(2px);
    box-shadow: 0 5px 15px rgba(59, 130, 246, 0.2);
    transition: all 0.1s ease;
}

.btn:hover::before {
    width: 100%;
}

.btn::after {
    content: "→";
    margin-left: 8px;
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    display: inline-block;
}

.btn:hover::after {
    transform: translateX(6px);
}

footer {
    background: linear-gradient(135deg, var(--primary-color) 0%, #0f172a 100%);
    color: rgba(255, 255, 255, 0.85);
    padding: 4rem 0 3rem;
    margin-top: 6rem;
    position: relative;
    overflow: hidden;
}

footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent 0%, rgba(59, 130, 246, 0.3) 50%, transparent 100%);
}

footer .container {
    position: relative;
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.footer-content {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    width: 100%;
    margin-bottom: 3rem;
}

.footer-column {
    flex: 1;
    min-width: 240px;
    margin-bottom: 2rem;
    padding: 0 1rem;
}

.footer-column h4 {
    color: white;
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 0.8rem;
}

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

.footer-column ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-column ul li {
    margin-bottom: 0.8rem;
    padding-left: 0;
}

.footer-column ul li::before {
    display: none;
}

.footer-column ul li a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: all 0.3s ease;
    display: inline-block;
}

.footer-column ul li a:hover {
    color: white;
    transform: translateX(3px);
}

.footer-column p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
    line-height: 1.7;
}

.social-icons {
    display: flex;
    gap: 15px;
    margin-top: 1.5rem;
}

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

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

.copyright {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    width: 100%;
}

.copyright p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.9rem;
    margin: 0;
}

/* 图标样式 */
i.fas {
    margin-right: 10px;
    color: var(--secondary-color);
    transition: var(--transition-standard);
}

h1 i.fas, h2 i.fas, h3 i.fas {
    font-size: 0.9em;
    vertical-align: middle;
    margin-right: 12px;
}

.highlight i.fas {
    color: var(--highlight-color);
}

li:hover i.fas {
    transform: scale(1.3);
    color: var(--accent-color);
}

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

/* 响应式设计 */
@media (max-width: 768px) {
    /* 汉堡菜单显示 */
    .menu-toggle {
        display: flex;
    }
    
    /* 菜单样式 */
    nav ul {
        position: absolute;
        top: var(--nav-height);
        left: 0;
        flex-direction: column;
        align-items: center;
        width: 100%;
        background-color: rgba(30, 41, 59, 0.98);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
        box-shadow: 0 8px 16px rgba(0,0,0,0.15);
        padding: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    }
    
    nav ul.active {
        max-height: 300px;
        padding: 1rem 0;
    }
    
    nav ul li {
        margin: 0.7rem 0;
        width: 80%;
        text-align: center;
    }
    
    nav ul li a {
        display: block;
        padding: 0.9rem 0;
        border-radius: 8px;
        background-color: rgba(255, 255, 255, 0.05);
    }
    
    nav ul li a:hover {
        background-color: rgba(255, 255, 255, 0.1);
    }
    
    nav ul li a::before {
        display: none;
    }
    
    .container {
        padding: 0 20px;
    }
    
    .content-section {
        padding: 2rem;
        border-radius: 12px;
    }
    
    h1 {
        font-size: 2.2rem;
    }
    
    h2 {
        font-size: 1.8rem;
    }
    
    .btn {
        padding: 0.9rem 2rem;
        width: 100%;
        text-align: center;
    }
    
    /* 汉堡菜单动画 */
    .menu-toggle.active span:nth-child(1) {
        transform: translateY(9px) rotate(45deg);
    }
    
    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .menu-toggle.active span:nth-child(3) {
        transform: translateY(-9px) rotate(-45deg);
    }
    
    .brand {
        font-size: 1.2rem;
    }
    
    .brand i {
        font-size: 1.4rem;
    }
    
    .footer-content {
        flex-direction: column;
    }
    
    .footer-column {
        width: 100%;
        margin-bottom: 2.5rem;
    }
}

/* 滚动显示效果 */
.reveal {
    opacity: 0;
    transform: translateY(50px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}