/* ========== 页面整体布局 ========== */
body, html {
    margin: 0;
    padding: 0;
    height: 100%;
    font-family: "Microsoft YaHei", sans-serif;
    background: linear-gradient(135deg, #667eea, #764ba2);
    display: flex;
    justify-content: center;
    align-items: center;
}

/* ========== 注册容器样式 ========== */
.register-container {
    width: 100%;
    max-width: 420px;        /* 容器缩小 */
    padding: 12px 20px;      /* 内边距缩小 */
    background: rgba(255, 255, 255, 0.95);
    border-radius: 12px;
    box-shadow: 0 12px 30px rgba(0,0,0,0.25);
    transition: transform 0.3s ease;
}

.register-container:hover {
    transform: translateY(-4px);
}

/* 标题居中 */
.register-container h2 {
    text-align: center;
    margin-bottom: 18px;
    margin-top: 0;
    font-size: 22px;       /* 缩小标题 */
    color: #333;
}

/* ========== 表单组 ========== */
.form-group {
    display: flex;
    flex-direction: column;
    margin-bottom: 10px;
}

.form-group label {
    font-weight: 600;
    font-size: 14px;       /* 缩小字体 */
    color: #333;
    margin-bottom: 4px;
}

.form-group input {
    padding: 8px;           /* 缩小内边距 */
    font-size: 14px;
    border: 1px solid #ccc;
    border-radius: 8px;
    box-sizing: border-box;
}

/* ========== 提示文字样式 ========== */
.form-group .form-text {
    display: block;
    margin-top: 3px;
    font-size: 13px;
    font-weight: 600;
    min-height: 16px;
}

.form-text.error { color: red; }
.form-text.success { color: green; }

#username-tip { color: red; }
#username-tip.success { color: green; }

/* ========== 验证码区域 ========== */
.form-group.captcha-group {
    display: flex;
    flex-direction: column; /* label 在上方 */
    align-items: flex-start;
}

.form-group.captcha-group .captcha-row {
    display: flex;          /* input 和 img 同行 */
    align-items: center;
    gap: 8px;               /* 间距略缩小 */
}

.form-group.captcha-group input {
    width: 345px;             /* 缩小宽度 */
    padding: 8px;
    font-size: 14px;
}

.form-group.captcha-group img {
    height: 32px;           /* 缩小 */
    width: 65px;
    border: 1px solid #ccc;
    border-radius: 6px;
    cursor: pointer;
    margin: 0;
}

/* 验证码提示 */
#captcha-tip {
    display: block;
    margin-top: 3px;
    font-size: 13px;
    font-weight: 600;
}
#captcha-tip.error { color: red; }
#captcha-tip.success { color: green; }

/* 底部链接居中 */
.register-container a {
    color: #667eea;
    text-decoration: none;
    font-size: 12px;
    display: block;
    margin: 12px auto 0 auto;
    text-align: center;
}
.register-container a:hover { 
    text-decoration: underline; 
}

/* ========== 注册按钮 ========== */
.register-container form button {
    width: 100%;
    padding: 9px;
    font-size: 14px;
    border: none;
    border-radius: 8px;
    background: #667eea;
    color: #fff;
    cursor: pointer;
    transition: background 0.3s ease;
}
.register-container form button:hover {
    background: #5a67d8;
}

/* ========== 邮箱自动补全弹出框 ========== */
.email-suggestions-popup {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: #fff;
    border: 1px solid #ccc;
    border-radius: 6px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    z-index: 1000;
    font-size: 12px;
}
.email-suggestions-popup div {
    padding: 4px 8px;
    cursor: pointer;
}
.email-suggestions-popup div:hover {
    background: #f0f0f0;
}

/* ========== 社交登录按钮 ========== */
.social-login {
    margin-top: 12px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px; 
    justify-content: space-between;
}

.social-login a {
    flex: 0 0 48%; 
    box-sizing: border-box;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 5px;
    padding: 9px;
    font-size: 14px;
    border-radius: 8px;
    color: #fff;
    text-decoration: none;
    transition: background 0.3s ease;
}

/* 按钮颜色 */
.google-login-btn { background: #db4437; }
.google-login-btn:hover { background: #c23321; }

.twitter-login-btn { background: #1DA1F2; }
.twitter-login-btn:hover { background: #0d95e8; }

.facebook-login-btn { background: #3b5998; }
.facebook-login-btn:hover { background: #2d4373; }

.tiktok-login-btn { background: #010101; }
.tiktok-login-btn:hover { background: #333; }

/* 手机端显示单列 */
@media screen and (max-width: 768px) {
    .social-login a {
        flex: 0 0 100%;
    }
}

/* ========== 响应式设计 ========== */
@media screen and (max-width: 1024px) {
    .register-container { max-width: 90%; padding: 20px; }
    .register-container h2 { font-size: 20px; }
    .form-group label { font-size: 13px; }
    .form-group input { font-size: 13px; padding: 7px; }
    .register-container form button { font-size: 13px; padding: 10px; }
}

@media screen and (max-width: 480px) {
    .register-container { padding: 10px; }
    .register-container h2 { font-size: 18px; }
    .form-group label { font-size: 12px; }
    .form-group input { font-size: 12px; padding: 6px; }
    .form-group.captcha-group img { height: 28px; width: 60px; }
    .register-container form button { font-size: 12px; padding: 8px; }
    .social-login a { flex: 1 1 100%; }
}