/* ==========================================================================
   项目最终样式表 (Final Stylesheet)
   版本: 1.0
   描述: 包含所有全局、组件、布局和响应式样式。
   ========================================================================== */

/* ---------------------------------- */
/* 1. 全局变量与基础样式 (Variables & Base) */
/* ---------------------------------- */
:root {
    --primary-color: #3498db;      /* 主题蓝 */
    --secondary-color: #2c3e50;    /* 深蓝灰 (用于标题) */
    --light-bg: #f8f9fa;           /* 浅灰色背景 */
    --dark-text: #34495e;           /* 主要文本颜色 */
    --light-text: #7f8c8d;          /* 辅助文本颜色 */
    --white-color: #ffffff;
    --border-color: #e9ecef;       /* 边框颜色 */
    --success-bg: #d4edda;
    --success-text: #155724;
    --error-bg: #f8d7da;
    --error-text: #721c24;
    --info-bg: #cce5ff;
    --info-text: #004085;
}

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

body {
    font-family: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.7;
    color: var(--dark-text);
    background-color: var(--white-color);
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }
a { color: var(--primary-color); text-decoration: none; transition: color 0.3s ease; }
a:hover { color: var(--secondary-color); }
hr { border: none; border-top: 1px solid var(--border-color); margin: 20px 0; }
img { max-width: 100%; height: auto; }

/* ---------------------------------- */
/* 2. 布局与通用组件 (Layout & Common) */
/* ---------------------------------- */
header[role="banner"] {
    background-color: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(5px);
    padding: 1rem 0;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

footer[role="contentinfo"] {
    background-color: var(--secondary-color);
    color: var(--white-color);
    text-align: center;
    padding: 2rem 0;
    margin-top: auto; /* 将页脚推到底部 */
}

.section { padding: 4rem 0; }
.section.alternate { background-color: var(--light-bg); }

.button {
    display: inline-block;
    background-color: var(--primary-color);
    color: var(--white-color);
    padding: 10px 25px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    text-align: center;
    transition: all 0.2s ease-in-out;
}

.button:hover {
    background-color: #2980b9;
    color: var(--white-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(52, 152, 219, 0.3);
}

/* ---------------------------------- */
/* 3. 导航栏 (Navbar) */
/* ---------------------------------- */
.navbar { display: flex; justify-content: space-between; align-items: center; min-height: 50px; }
.navbar-brand a { text-decoration: none; color: var(--secondary-color); }
.navbar-brand span { display: block; line-height: 1.3; }
.navbar-brand .title-line-1 { font-size: 1rem; font-weight: 600; }
.navbar-brand .title-line-2 { font-size: 0.8rem; font-weight: 400; color: var(--light-text); }
.navbar-menu { display: flex; align-items: center; gap: 1.5rem; }
.navbar-links { display: flex; list-style: none; gap: 1rem; }
.navbar-links a { color: var(--dark-text); font-weight: 500; font-size: 0.95rem; padding: 8px 12px; border-radius: 6px; transition: all 0.2s ease-in-out; }
.navbar-links a:hover { color: var(--primary-color); background-color: var(--light-bg); }
.menu-toggle { display: none; color: var(--dark-text); background: none; border: none; font-size: 2rem; cursor: pointer; z-index: 1001; }

/* ---------------------------------- */
/* 4. 表单 (Forms) */
/* ---------------------------------- */
.form-group { margin-bottom: 1.5rem; }
.form-group label { display: block; margin-bottom: 5px; font-weight: 500; }
.form-group input[type="text"], .form-group input[type="email"], .form-group textarea { width: 100%; padding: 12px; border: 1px solid #ccc; border-radius: 6px; font-size: 1rem; transition: border-color 0.3s, box-shadow 0.3s; }
.form-group input:focus, .form-group textarea:focus { outline: none; border-color: var(--primary-color); box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2); }

/* ---------------------------------- */
/* 5. Cookie 横幅 (Cookie Banner) */
/* ---------------------------------- */
.cookie-consent-banner { position: fixed; bottom: 0; left: 0; width: 100%; background-color: rgba(44, 62, 80, 0.95); color: var(--white-color); padding: 15px 30px; box-shadow: 0 -2px 10px rgba(0,0,0,0.2); display: flex; justify-content: space-between; align-items: center; z-index: 1000; transform: translateY(100%); transition: transform 0.5s ease-in-out; }
.cookie-consent-banner.show { transform: translateY(0); }
.cookie-consent-banner p { margin: 0 20px 0 0; font-size: 14px; }
.cookie-consent-banner .button { white-space: nowrap; }

/* ---------------------------------- */
/* 6. 页面特定样式 (Page-Specific Styles) */
/* ---------------------------------- */
.hero-header, .hero { text-align: center; padding: 4rem 2rem; background-color: var(--light-bg); border-radius: 8px; margin-bottom: 2rem; }
.hero-header h1, .hero h1 { font-size: 2.5rem; color: var(--secondary-color); margin-bottom: 0.5rem; }
.hero-header p, .hero p { font-size: 1.2rem; color: var(--light-text); max-width: 700px; margin: 0 auto 1.5rem auto; }

.info-card { background: var(--white-color); padding: 2rem; border-radius: 8px; box-shadow: 0 4px 15px rgba(0,0,0,0.05); border-top: 3px solid var(--primary-color); }
.info-card h3 { margin-top: 0; color: var(--secondary-color); font-size: 1.5rem; border-bottom: 1px solid var(--border-color); padding-bottom: 10px; margin-bottom: 1rem; }
.info-card ul { padding-left: 20px; }

.content-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(350px, 1fr)); gap: 2rem; }
.full-width-card { grid-column: 1 / -1; }
.chart-container { position: relative; height: 350px; }

.heatmap-table { width: 100%; border-collapse: collapse; margin-top: 1rem; }
.heatmap-table th, .heatmap-table td { border: 1px solid var(--border-color); padding: 12px; text-align: center; }
.heatmap-table th { background-color: var(--light-bg); font-weight: 600; }
.heatmap-table td { font-size: 1.1rem; font-weight: 500; color: var(--white-color); }

/* ---------------------------------- */
/* 7. 语言下拉菜单 (Language Dropdown) */
/* ---------------------------------- */
.language-dropdown { position: relative; display: inline-block; }
.language-button { background-color: transparent; border: 1px solid var(--border-color); color: var(--dark-text); padding: 8px 12px; font-size: 0.9rem; border-radius: 6px; cursor: pointer; display: flex; align-items: center; gap: 8px; transition: background-color 0.2s ease; }
.language-button:hover { background-color: var(--light-bg); }
.language-button .arrow { transition: transform 0.3s ease; }
.language-options { display: none; opacity: 0; visibility: hidden; transform: translateY(10px); transition: all 0.3s ease; position: absolute; background-color: var(--white-color); min-width: 160px; box-shadow: 0 8px 16px rgba(0,0,0,0.1); border: 1px solid var(--border-color); z-index: 1; list-style: none; padding: 10px 0; border-radius: 6px; right: 0; margin-top: 8px; }
.language-dropdown.active .language-options { display: block; opacity: 1; visibility: visible; transform: translateY(0); }
.language-dropdown.active .language-button .arrow { transform: rotate(180deg); }
.language-options li a { color: var(--dark-text); padding: 10px 20px; text-decoration: none; display: block; font-size: 0.9rem; font-weight: normal; white-space: nowrap; }
.language-options li a:hover { background-color: var(--light-bg); }
.language-options li a.active { background-color: var(--primary-color); color: var(--white-color); font-weight: bold; }

/* ---------------------------------- */
/* 8. 响应式设计 (Responsive Design) */
/* ---------------------------------- */
@media (max-width: 992px) {
    .menu-toggle { display: block; }
    .navbar-menu { display: none; position: fixed; width: 100%; height: 100vh; top: 0; left: 0; background-color: var(--white-color); flex-direction: column; justify-content: center; gap: 2rem; transition: transform 0.3s ease-in-out; transform: translateX(100%); }
    .navbar-menu.active { display: flex; transform: translateX(0); }
    .navbar-links { flex-direction: column; gap: 1rem; align-items: center; }
    .navbar-links a { font-size: 1.5rem; }
    .desktop-switcher { display: block; } /* 在移动菜单中也显示PC版下拉菜单 */
}