/**
 * 文件名：login.css
 * 功能：登录页面样式文件（改进版）
 * 作者：孟立
 * 创建日期：2026-02-26
 */

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

/* 背景装饰 */
body::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: animateBg 20s linear infinite;
    z-index: 0;
}

@keyframes animateBg {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.login-container {
    width: 100%;
    max-width: 400px;
    padding: 20px;
    position: relative;
    z-index: 1;
}

.login-box {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

/* 系统标题区域 */
.system-title {
    text-align: center;
    padding: 30px 20px 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.logo-icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 15px;
    font-size: 32px;
}

.system-title h1 {
    font-size: 24px;
    font-weight: 600;
    margin: 0 0 10px 0;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.subtitle {
    font-size: 14px;