html {
    height: 100%;
    font-family: PingFangSC-Light, 'helvetica neue', 'hiragino sans gb', arial, 'microsoft yahei ui', 'microsoft yahei', simsun, sans-serif;
    font-size: 14px;
}

body.signin {
    background: #18c8f6;
    height: auto;
    background: url("../img/backg01.jpg") no-repeat center fixed; 
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;

}
/* ===== 基础重置与全局样式 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

body {
    background: linear-gradient(135deg, #f5f7fa 0%, #e4edf5 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    color: #333;
}

/* ===== 登录主容器 ===== */
.login-container {
    width: 100%;
    max-width: 420px;
    background-color: #ffffff;
    border-radius: 16px;
    box-shadow: 0 15px 35px rgba(50, 100, 150, 0.1);
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.login-container:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(50, 100, 150, 0.15);
}

/* ===== 顶部横幅区域 ===== */
.login-header {
    background: linear-gradient(to right, #2c80ff, #1a5dc1);
    color: white;
    padding: 30px 20px;
    text-align: center;
}

.system-title {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 5px;
    letter-spacing: 0.5px;
}

.system-subtitle {
    font-size: 15px;
    opacity: 0.9;
    font-weight: 400;
}

/* ===== 登录表单区域 ===== */
.login-form {
    padding: 35px 30px;
}

.welcome-text {
    font-size: 20px;
    color: #2c3e50;
    margin-bottom: 8px;
    font-weight: 600;
}

.system-description {
    color: #7f8c8d;
    margin-bottom: 30px;
    font-size: 14px;
    line-height: 1.5;
}

/* ===== 表单组 ===== */
.form-group {
    margin-bottom: 22px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #2c3e50;
    font-size: 14px;
}

.input-with-icon {
    position: relative;
}

.input-with-icon i {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: #95a5a6;
    font-size: 18px;
}

.input-with-icon input {
    width: 100%;
    padding: 15px 20px 15px 50px;
    border: 2px solid #e1e8ed;
    border-radius: 10px;
    font-size: 16px;
    transition: all 0.3s;
    background-color: #fdfdfd;
}

.input-with-icon input:focus {
    outline: none;
    border-color: #2c80ff;
    background-color: #fff;
    box-shadow: 0 0 0 3px rgba(44, 128, 255, 0.1);
}

/* ===== 记住我与链接 ===== */
.form-options {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 28px;
    font-size: 14px;
}

.remember-me {
    display: flex;
    align-items: center;
}

.remember-me input[type="checkbox"] {
    margin-right: 8px;
    width: 18px;
    height: 18px;
    accent-color: #2c80ff;
}

.forgot-link {
    color: #2c80ff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

.forgot-link:hover {
    color: #1a5dc1;
    text-decoration: underline;
}

/* ===== 登录按钮 ===== */
.login-button {
    width: 100%;
    padding: 16px;
    background: linear-gradient(to right, #2c80ff, #1a5dc1);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 17px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    letter-spacing: 0.5px;
}

.login-button:hover {
    background: linear-gradient(to right, #1a5dc1, #1552a3);
    box-shadow: 0 5px 15px rgba(44, 128, 255, 0.3);
}

.login-button:active {
    transform: scale(0.98);
}

/* ===== 页脚技术支持 ===== */
.login-footer {
    text-align: center;
    padding: 22px;
    border-top: 1px solid #eee;
    color: #95a5a6;
    font-size: 13px;
    background-color: #f9fbfd;
}

.tech-support {
    margin-top: 5px;
    font-size: 13px;
}

/* ===== 响应式调整 ===== */
@media (max-width: 480px) {
    .login-container {
        border-radius: 12px;
    }

    .login-header {
        padding: 25px 20px;
    }

    .system-title {
        font-size: 24px;
    }

    .login-form {
        padding: 25px 20px;
    }

    .welcome-text {
        font-size: 18px;
    }
}