:root {
    --primary-color: #0056b3;
    --primary-hover: #004494;
    --text-dark: #1a1a1a;
    --text-gray: #666;
    --border-color: #e0e0e0;
    --bg-gradient: linear-gradient(135deg, #0056b3 0%, #002a5c 100%);
}

body {
    margin: 0;
    padding: 0;
    font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background-color: #f5f7fa;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* 主容器 */
.auth-container {
    width: 1000px;
    height: 690px;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.1);
    display: flex;
    overflow: hidden;
}

/* 左侧：品牌区 */
.brand-section {
    flex: 0.8;
    background: var(--bg-gradient);
    color: #fff;
    padding: 60px 40px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    position: relative;
}

/* 装饰背景纹理 */
.brand-section::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background-image: radial-gradient(rgba(255,255,255,0.1) 1px, transparent 1px);
    background-size: 30px 30px;
    opacity: 0.5;
}

.brand-header h1 {
    font-size: 28px;
    margin: 0 0 10px 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.brand-features {
    margin-top: 40px;
    z-index: 1;
}
.feature-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 25px;
}
.feature-icon {
    background: rgba(255,255,255,0.2);
    width: 36px;
    height: 36px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 15px;
    font-size: 16px;
}
.feature-text h3 { margin: 0 0 5px 0; font-size: 16px; }
.feature-text p { margin: 0; font-size: 13px; opacity: 0.8; line-height: 1.4; }

.brand-footer { font-size: 12px; opacity: 0.6; z-index: 1; }

/* 右侧：表单区 */
.form-section {
    flex: 1;
    padding: 60px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.form-header { margin-bottom: 30px; }
.form-header h2 { font-size: 26px; color: var(--text-dark); margin: 0 0 10px 0; }
.form-header p { color: var(--text-gray); font-size: 14px; }
.form-header a { color: var(--primary-color); text-decoration: none; font-weight: 600; }

.input-group { margin-bottom: 20px; position: relative; }
.input-label { display: block; font-size: 14px; font-weight: 600; color: #333; margin-bottom: 8px; }

.input-field {
    width: 100%;
    padding: 12px 15px;
    font-size: 14px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-sizing: border-box; /* 关键：防止padding撑大宽度 */
    transition: all 0.3s;
    background: #fafafa;
}
.input-field:focus {
    outline: none;
    border-color: var(--primary-color);
    background: #fff;
    box-shadow: 0 0 0 3px rgba(0, 86, 179, 0.1);
}

/* 验证码行 */
.verify-row {
    display: flex;
    gap: 10px;
}
.btn-send-code {
    white-space: nowrap;
    padding: 0 20px;
    background: #e3f2fd;
    color: var(--primary-color);
    border: 1px solid transparent;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}
.btn-send-code:hover { background: #d1e9fc; }
.btn-send-code:disabled {
    background: #f5f5f5;
    color: #999;
    cursor: not-allowed;
}

.submit-btn {
    width: 100%;
    padding: 14px;
    background: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    margin-top: 10px;
    transition: background 0.3s;
}
.submit-btn:hover { background: var(--primary-hover); }

.terms-checkbox {
    display: flex;
    align-items: center;
    margin-top: 15px;
    font-size: 12px;
    color: var(--text-gray);
}
.terms-checkbox input { margin-right: 8px; }
.terms-checkbox a { color: var(--text-dark); text-decoration: underline; }

/* 错误提示 */
.error-msg {
    color: #dc3545;
    font-size: 12px;
    margin-top: 5px;
    display: none; /* 默认隐藏 */
    animation: shake 0.3s ease-in-out;
}

@keyframes shake {
    0% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    50% { transform: translateX(5px); }
    100% { transform: translateX(0); }
}