/* 自定义Bootstrap风格CSS，专为登录页面优化 */

/* 基础重置和容器样式 */
html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    box-sizing: border-box;
}

*, *:before, *:after {
    box-sizing: inherit;
}

body {
    font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
    font-size: 1rem;
    line-height: 1.5;
}

/* 网格系统简化版 */
.container {
    width: 100%;
    padding-right: 15px;
    padding-left: 15px;
    margin-right: auto;
    margin-left: auto;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    font-weight: 400;
    text-align: center;
    vertical-align: middle;
    cursor: pointer;
    user-select: none;
    border: 1px solid transparent;
    padding: .375rem .75rem;
    font-size: 1rem;
    line-height: 1.5;
    border-radius: .25rem;
    transition: color .15s ease-in-out,background-color .15s ease-in-out,border-color .15s ease-in-out,box-shadow .15s ease-in-out;
}

.btn-primary {
    color: #fff;
    background-color: #007bff;
    border-color: #007bff;
}

.btn-primary:hover {
    color: #fff;
    background-color: #0069d9;
    border-color: #0062cc;
}

/* 表单控件 */
.form-control {
    display: block;
    width: 100%;
    height: calc(1.5em + .75rem + 2px);
    padding: .375rem .75rem;
    font-size: 1rem;
    font-weight: 400;
    line-height: 1.5;
    color: #495057;
    background-color: #fff;
    background-clip: padding-box;
    border: 1px solid #ced4da;
    border-radius: .25rem;
    transition: border-color .15s ease-in-out,box-shadow .15s ease-in-out;
}

.form-control:focus {
    color: #495057;
    background-color: #fff;
    border-color: #80bdff;
    outline: 0;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
}

/* 警告提示框 */
.alert {
    position: relative;
    padding: .75rem 1.25rem;
    margin-bottom: 1rem;
    border: 1px solid transparent;
    border-radius: .25rem;
}

.alert-info {
    color: #0c5460;
    background-color: #d1ecf1;
    border-color: #bee5eb;
}

.alert-danger {
    color: #721c24;
    background-color: #f8d7da;
    border-color: #f5c6cb;
}

.alert-warning {
    color: #856404;
    background-color: #fff3cd;
    border-color: #ffeeba;
}

.alert-success {
    color: #155724;
    background-color: #d4edda;
    border-color: #c3e6cb;
}