/* ========== Reset & Base ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    color: #333333;
    background-color: #ffffff;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
}

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

/* ========== Navigation ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
}

.navbar.scrolled {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

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

.nav-logo {
    font-size: 1.2rem;
    font-weight: 700;
    color: #0066FF;
}

.nav-logo span {
    color: #0066FF;
}

.nav-menu {
    display: flex;
    gap: 40px;
}

.nav-link {
    font-size: 0.95rem;
    color: #666666;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: #0066FF;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #0066FF;
    transition: width 0.3s ease;
}

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

.nav-right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.lang-switcher {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    padding: 6px 12px;
    border-radius: 20px;
    transition: background 0.3s ease;
}

.lang-switcher:hover {
    background: #f5f7fa;
}

.lang-switcher .lang-text {
    font-size: 0.9rem;
    color: #666666;
}

.lang-switcher .lang-icon {
    font-size: 1rem;
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: #333333;
    border-radius: 2px;
    transition: all 0.3s ease;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* ========== Footer ========== */
.footer {
    background: #1a1a2e;
    color: #ffffff;
    padding: 60px 0 30px;
}

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

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h3 {
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: #ffffff;
}

.footer-col ul li {
    margin-bottom: 12px;
}

.footer-col ul li a {
    color: #b0b0b0;
    transition: color 0.3s ease;
}

.footer-col ul li a:hover {
    color: #0066FF;
}

.footer-contact p {
    color: #b0b0b0;
    margin-bottom: 8px;
    font-size: 0.9rem;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    color: #888888;
    font-size: 0.85rem;
}

/* ========== Responsive Design ========== */
@media (max-width: 1024px) {
    .nav-menu {
        gap: 30px;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        gap: 0;
        padding: 20px;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-link {
        padding: 15px 0;
        border-bottom: 1px solid #f0f0f0;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

/* ========== Utility Classes ========== */
.text-center {
    text-align: center;
}

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }