* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

body {
    background: linear-gradient(135deg, #6e8efb, #a777e3);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.login-container {
    background: white;
    border-radius: 16px;
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
    width: 100%;
    max-width: 420px;
    padding: 40px;
    position: relative;
    overflow: hidden;
}

.login-container::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 6px;
    background: linear-gradient(to right, #6e8efb, #a777e3);
}

h2 {
    text-align: center;
    color: #333;
    margin-bottom: 30px;
    font-weight: 600;
    font-size: 28px;
    position: relative;
}

h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(to right, #6e8efb, #a777e3);
    border-radius: 2px;
}

.error-message {
    background-color: #ffebee;
    color: #f44336;
    padding: 12px 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    border-left: 4px solid #f44336;
    display: flex;
    align-items: center;
    gap: 10px;
    animation: fadeIn 0.4s ease-out;
}

.error-message i {
    font-size: 20px;
}

.form-group {
    margin-bottom: 24px;
    position: relative;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
    font-size: 15px;
}

input {
    width: 100%;
    padding: 14px 15px 14px 45px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 16px;
    transition: all 0.3s ease;
    outline: none;
}

input:focus {
    border-color: #6e8efb;
    box-shadow: 0 0 0 3px rgba(110, 142, 251, 0.2);
}

.input-icon {
    position: absolute;
    left: 15px;
    top: 40px;
    color: #777;
    font-size: 18px;
}

button {
    width: 100%;
    padding: 14px;
    background: linear-gradient(to right, #6e8efb, #a777e3);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 17px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(110, 142, 251, 0.3);
    margin-top: 10px;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(110, 142, 251, 0.4);
}

button:active {
    transform: translateY(1px);
}

.register-link {
    display: block;
    text-align: center;
    margin-top: 25px;
    color: #666;
    text-decoration: none;
    font-size: 15px;
    transition: color 0.3s ease;
    position: relative;
}

.register-link:hover {
    color: #6e8efb;
}

.register-link::after {
    content: '→';
    position: absolute;
    margin-left: 5px;
    transition: transform 0.3s ease;
}

.register-link:hover::after {
    transform: translateX(3px);
}

.divider {
    display: flex;
    align-items: center;
    margin: 25px 0;
    color: #999;
}

.divider::before,
.divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: #e0e0e0;
}

.divider span {
    padding: 0 15px;
    font-size: 14px;
}

.social-login {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 20px;
}

.social-btn {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 20px;
    cursor: pointer;
    transition: transform 0.3s ease;
}

.social-btn:hover {
    transform: translateY(-3px);
}

.social-btn.wechat {
    background: linear-gradient(to right, #09bb07, #2aae67);
}

.social-btn.qq {
    background: linear-gradient(to right, #12b7f5, #2a6cb3);
}

.social-btn.weibo {
    background: linear-gradient(to right, #e6162d, #f05b5b);
}

.footer {
    text-align: center;
    margin-top: 30px;
    color: #888;
    font-size: 13px;
    line-height: 1.6;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 响应式设计 */
@media (max-width: 480px) {
    .login-container {
        padding: 30px 20px;
    }
    
    h2 {
        font-size: 24px;
    }
    
    input {
        padding: 12px 15px 12px 40px;
    }
    
    button {
        padding: 13px;
    }
}