/* ============================================
   RailwaysLab 公共样式库
   包含：重置、导航栏、认证、工具类、响应式
   ============================================ */

/* ---------- 基础重置 ---------- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2196F3;
    --secondary-color: #1565C0;
    --text-color: #333;
    --bg-color: #fff;
    --card-bg: #f8f9fa;
    --border-color: #e0e0e0;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --card-hover-bg: #e3f2fd;
    --content-width: 90vw;
    --content-height: calc(var(--content-width) * 9 / 16);
    --navbar-bg-light: rgba(255, 255, 255, 0.85);
    --navbar-bg-dark: rgba(18, 18, 18, 0.85);
    --navbar-blur: 20px;
}

.dark-mode {
    --primary-color: #2196F3;
    --secondary-color: #0D47A1;
    --text-color: #e0e0e0;
    --bg-color: #121212;
    --card-bg: #1e1e1e;
    --border-color: #333;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    --card-hover-bg: #1a237e;
}

html.dark-mode, body.dark-mode {
    background: linear-gradient(135deg, #1e1e1e 0%, #121212 100%) !important;
    color: var(--text-color) !important;
}

body {
    font-family: 'Segoe UI', system-ui, sans-serif;
    min-height: 100vh;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    color: #333;
    margin: 0 !important;
    transition: background-color 0.3s, color 0.3s;
}

/* ---------- 导航栏 ---------- */
#navbar-container {
    background: rgba(255, 255, 255, 0.4) !important;
    backdrop-filter: blur(25px) saturate(200%) !important;
    -webkit-backdrop-filter: blur(25px) saturate(200%) !important;
    border-bottom: 1px solid rgba(255, 255, 255, 0.5) !important;
    position: fixed !important;
    top: 0 !important;
    left: 0 !important;
    right: 0 !important;
    width: 100vw !important;
    z-index: 9999 !important;
    margin: 0 !important;
    padding: 0 !important;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1) !important;
    transition: all 0.3s ease !important;
}

#navbar-container.scrolled {
    background: rgba(255, 255, 255, 0.5) !important;
    box-shadow: 0 6px 30px rgba(0, 0, 0, 0.15) !important;
}

.nav-container {
    max-width: 1200px !important;
    width: 100% !important;
    margin: 0 auto !important;
    padding: 0 20px !important;
    display: flex !important;
    justify-content: space-between !important;
    align-items: center !important;
    height: 70px !important;
}

.nav-left {
    display: flex !important;
    align-items: center !important;
    gap: 2rem !important;
}

.nav-right {
    display: flex !important;
    align-items: center !important;
    gap: 1rem !important;
}

.logo {
    font-size: 1.5rem !important;
    font-weight: bold !important;
    color: #333 !important;
    text-decoration: none !important;
    transition: color 0.3s ease !important;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo:hover {
    color: #2196F3 !important;
}

.nav-links {
    display: flex !important;
    gap: 2rem !important;
    list-style: none !important;
    margin: 0 !important;
    padding: 0 !important;
}

.nav-links > a {
    color: #333 !important;
    text-decoration: none !important;
    font-weight: 500 !important;
    transition: color 0.3s ease !important;
    position: relative !important;
    padding: 0.5rem 0 !important;
    display: flex !important;
    align-items: center !important;
}

.nav-links > a::after {
    content: '' !important;
    position: absolute !important;
    bottom: -5px !important;
    left: 0 !important;
    width: 0% !important;
    height: 2px !important;
    background: #2196F3 !important;
    transition: width 0.3s ease !important;
    border-radius: 1px !important;
}

.nav-links > a:hover::after,
.nav-links > a.active::after {
    width: 100% !important;
}

.nav-links > a:hover {
    color: #2196F3 !important;
}

.hamburger {
    display: none !important;
    background: none !important;
    border: none !important;
    color: #333 !important;
    font-size: 1.5rem !important;
    cursor: pointer !important;
    padding: 5px;
    border-radius: 4px;
    transition: background 0.3s;
}

.hamburger:hover {
    background: rgba(0, 0, 0, 0.05);
}

/* ---------- 下拉菜单 ---------- */
.dropdown {
    position: relative !important;
}

.dropbtn {
    display: flex !important;
    align-items: center !important;
    gap: 0.5rem !important;
    color: #333 !important;
    text-decoration: none !important;
    font-weight: 500 !important;
    cursor: pointer !important;
    position: relative !important;
    padding: 0.5rem 0 !important;
    transition: color 0.3s ease !important;
}

.dropbtn::after {
    content: '' !important;
    position: absolute !important;
    bottom: -5px !important;
    left: 0 !important;
    width: 0% !important;
    height: 2px !important;
    background: #2196F3 !important;
    transition: width 0.3s ease !important;
    border-radius: 1px !important;
}

.dropbtn:hover::after {
    width: 100% !important;
}

.dropbtn:hover {
    color: #2196F3 !important;
}

.dropdown-content {
    position: absolute !important;
    top: 100% !important;
    left: 0 !important;
    background: rgba(255, 255, 255, 0.9) !important;
    backdrop-filter: blur(20px) saturate(200%) !important;
    -webkit-backdrop-filter: blur(20px) saturate(200%) !important;
    border: 1px solid rgba(255, 255, 255, 0.6) !important;
    border-radius: 12px !important;
    min-width: 200px !important;
    padding: 0.5rem 0 !important;
    margin-top: 0.5rem !important;
    opacity: 0 !important;
    visibility: hidden !important;
    transform: translateY(-10px) !important;
    transition: all 0.3s ease !important;
    box-shadow: 0 10px 35px rgba(0, 0, 0, 0.15) !important;
    z-index: 10000 !important;
    overflow: hidden;
}

.dropdown:hover .dropdown-content {
    opacity: 1 !important;
    visibility: visible !important;
    transform: translateY(0) !important;
}

.dropdown-content a {
    display: block !important;
    padding: 0.75rem 1.5rem !important;
    color: #333 !important;
    text-decoration: none !important;
    transition: all 0.3s ease !important;
    position: relative !important;
}

.dropdown-content a::after {
    content: '' !important;
    position: absolute !important;
    bottom: 0 !important;
    left: 1.5rem !important;
    right: 1.5rem !important;
    width: 0% !important;
    height: 1px !important;
    background: #2196F3 !important;
    transition: width 0.3s ease !important;
}

.dropdown-content a:hover::after {
    width: calc(100% - 3rem) !important;
}

.dropdown-content a:hover {
    background: rgba(33, 150, 243, 0.1) !important;
    color: #2196F3 !important;
}

/* ---------- 认证相关 - 纯文本风格 ---------- */
.auth-buttons {
    display: flex !important;
    gap: 0.75rem !important;
    align-items: center !important;
}

#authEntryBtn {
    color: #2196F3;
    text-decoration: none;
    font-weight: 500;
    position: relative;
    padding: 0.5rem 0;
    transition: color 0.3s ease;
    cursor: pointer;
}

#authEntryBtn::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0%;
    height: 2px;
    background: #2196F3;
    transition: width 0.3s ease;
    border-radius: 1px;
}

#authEntryBtn:hover {
    color: #2196F3;
}

#authEntryBtn:hover::after {
    width: 100%;
}

#userMenu {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

#userGreeting {
    color: #333;
    font-weight: 500;
}

.nav-text-link {
    color: #333;
    text-decoration: none;
    font-weight: 500;
    position: relative;
    padding: 0.5rem 0;
    transition: color 0.3s ease;
    cursor: pointer;
}

.nav-text-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0%;
    height: 2px;
    background: #2196F3;
    transition: width 0.3s ease;
    border-radius: 1px;
}

.nav-text-link:hover {
    color: #2196F3;
}

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

#signOutBtn {
    color: #666;
    text-decoration: none;
    font-weight: 500;
    position: relative;
    padding: 0.5rem 0;
    transition: color 0.3s ease;
    cursor: pointer;
}

#signOutBtn::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0%;
    height: 2px;
    background: #f44336;
    transition: width 0.3s ease;
    border-radius: 1px;
}

#signOutBtn:hover {
    color: #f44336;
}

#signOutBtn:hover::after {
    width: 100%;
}

/* ---------- 认证按钮 ---------- */
.auth-btn {
    padding: 0.5rem 1rem !important;
    border-radius: 8px !important;
    text-decoration: none !important;
    font-weight: 500 !important;
    font-size: 0.9rem !important;
    transition: all 0.3s ease !important;
}

.login-btn {
    color: #2196F3 !important;
    border: 1px solid #2196F3 !important;
    background: transparent !important;
}

.login-btn:hover {
    background: #2196F3 !important;
    color: white !important;
}

.register-btn {
    background: #2196F3 !important;
    color: white !important;
    border: 1px solid #2196F3 !important;
}

.register-btn:hover {
    background: #1565C0 !important;
    border-color: #1565C0 !important;
}

/* ---------- 深色模式 - 导航 ---------- */
.dark-mode #navbar-container {
    background: rgba(30, 30, 30, 0.4) !important;
    border-bottom: 1px solid rgba(255, 255, 255, 0.15) !important;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3) !important;
}

.dark-mode #navbar-container.scrolled {
    background: rgba(30, 30, 30, 0.5) !important;
}

.dark-mode .logo,
.dark-mode .nav-links > a {
    color: #e0e0e0 !important;
}

.dark-mode .hamburger {
    color: #e0e0e0 !important;
}

.dark-mode .hamburger:hover {
    background: rgba(255, 255, 255, 0.1);
}

.dark-mode #userGreeting {
    color: #e0e0e0 !important;
}

.dark-mode .nav-text-link {
    color: #e0e0e0;
}

.dark-mode .nav-text-link:hover {
    color: #2196F3;
}

.dark-mode #signOutBtn {
    color: #aaa;
}

.dark-mode #signOutBtn:hover {
    color: #f44336;
}

.dark-mode .dropdown-content {
    background: rgba(30, 30, 30, 0.9) !important;
    border: 1px solid rgba(255, 255, 255, 0.2) !important;
}

.dark-mode .dropdown-content a {
    color: #e0e0e0 !important;
}

.dark-mode .dropdown-content a:hover {
    background: rgba(33, 150, 243, 0.2) !important;
    color: #2196F3 !important;
}

.dark-mode .dropbtn {
    color: #e0e0e0 !important;
}

/* ---------- 页脚 ---------- */
footer {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 3rem;
}

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

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

.text-btn {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1rem;
    font-weight: 500;
    padding: 0.5rem 0;
    cursor: pointer;
    position: relative;
    display: inline-block;
    transition: color 0.3s;
}

.text-btn::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0%;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

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

.text-btn:hover::after,
.text-btn.active::after {
    width: 100%;
}

/* ---------- 移动端响应式 ---------- */
@media (max-width: 768px) {
    .nav-links {
        display: none !important;
        position: absolute !important;
        top: 100% !important;
        left: 0 !important;
        right: 0 !important;
        background: rgba(255, 255, 255, 0.95) !important;
        backdrop-filter: blur(25px) saturate(200%) !important;
        flex-direction: column !important;
        padding: 1rem !important;
        gap: 0 !important;
        z-index: 10000 !important;
        border-radius: 0 0 12px 12px !important;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15) !important;
    }

    .dark-mode .nav-links {
        background: rgba(30, 30, 30, 0.95) !important;
    }

    .nav-links.active {
        display: flex !important;
    }

    .nav-links a {
        padding: 1rem 0 !important;
        border-bottom: 1px solid rgba(0, 0, 0, 0.1) !important;
    }

    .dark-mode .nav-links a {
        border-bottom: 1px solid rgba(255, 255, 255, 0.1) !important;
    }

    .nav-links > a::after {
        display: none !important;
    }

    .hamburger {
        display: block !important;
    }

    .dropdown-content {
        position: static !important;
        display: none !important;
        box-shadow: none !important;
        border: none !important;
        border-radius: 0 !important;
        margin-top: 0 !important;
        background: transparent !important;
        backdrop-filter: none !important;
        -webkit-backdrop-filter: none !important;
        opacity: 1 !important;
        visibility: visible !important;
        transform: none !important;
        padding-left: 1rem !important;
    }

    .dropdown.active .dropdown-content {
        display: block !important;
    }

    .dropdown-content a::after {
        display: none !important;
    }

    .dropbtn::after {
        display: none !important;
    }
}

/* ---------- 动画 ---------- */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ---------- Toast 提示 ---------- */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0,0,0,0.8);
    color: white;
    padding: 10px 20px;
    border-radius: 30px;
    z-index: 10000;
    display: none;
}