* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #1a1a3a;
    min-height: 100vh;
    position: relative;
    overflow-x: hidden;
}

/* 背景图案 */
.background-pattern {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #1a1a3a url('bg.svg') no-repeat center center;
    background-size: cover;
    z-index: -1;
}

/* 登录容器 */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
    position: relative;
    z-index: 1;
}

/* 登录卡片 */
.login-card {
    background: #ffffff;
    border-radius: 12px;
    box-shadow: 
        0 20px 40px rgba(0, 0, 0, 0.1),
        0 8px 16px rgba(0, 0, 0, 0.08),
        0 4px 8px rgba(0, 0, 0, 0.04);
    padding: 48px 40px 40px;
    width: 100%;
    max-width: 400px;
    position: relative;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.login-card.loaded {
    opacity: 1;
    transform: translateY(0);
}

/* Logo部分 */
.logo-section {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 40px;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
}

.logo img {
    height: 64px;
    width: auto;
    max-width: 200px;
    object-fit: contain;
    display: block;
}

.brand-name {
    font-size: 20px;
    font-weight: 600;
    color: #1a1a1a;
    letter-spacing: -0.02em;
}

/* 表单部分 */
.form-section {
    width: 100%;
}

/* 步骤控制 */
.step-email,
.step-password {
    display: none;
    opacity: 0;
    transform: translateX(20px);
    transition: all 0.3s ease;
}

.step-email.active,
.step-password.active {
    display: block;
    opacity: 1;
    transform: translateX(0);
}

.title {
    font-size: 32px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 8px;
    text-align: left;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.subtitle {
    font-size: 16px;
    color: #666666;
    margin-bottom: 32px;
    text-align: left;
    line-height: 1.4;
}

/* 输入组 */
.input-group {
    margin-bottom: 24px;
}

.input-label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: #1a1a1a;
    margin-bottom: 8px;
    line-height: 1.4;
}

.required {
    color: #e74c3c;
    font-weight: 500;
}

.email-input,
.password-input {
    width: 100%;
    height: 48px;
    padding: 12px 16px;
    border: 1.5px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    color: #1a1a1a;
    background: #ffffff;
    transition: all 0.2s ease;
    outline: none;
    font-family: inherit;
}

.email-input::placeholder,
.password-input::placeholder {
    color: #9ca3af;
    font-size: 16px;
}

.email-input:focus,
.password-input:focus {
    border-color: #4A90E2;
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
}

.email-input:hover,
.password-input:hover {
    border-color: #c1c9d0;
}

/* 输入框状态样式 */
.input-group.focused .email-input,
.input-group.focused .password-input {
    border-color: #4A90E2;
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
}

.input-group.valid .email-input,
.input-group.valid .password-input {
    border-color: #22c55e;
}

.input-group.invalid .email-input,
.input-group.invalid .password-input {
    border-color: #ef4444;
}

/* 消息提示样式 */
.error-message,
.success-message {
    margin-top: 8px;
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 13px;
    font-weight: 500;
    animation: slideIn 0.3s ease;
}

.error-message {
    background: rgba(239, 68, 68, 0.1);
    color: #dc2626;
    border: 1px solid rgba(239, 68, 68, 0.2);
}

.success-message {
    background: rgba(34, 197, 94, 0.1);
    color: #16a34a;
    border: 1px solid rgba(34, 197, 94, 0.2);
}

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

/* 按钮样式 */
.continue-btn,
.signin-btn {
    width: 100%;
    height: 48px;
    background: #4A90E2;
    color: #ffffff;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    margin-bottom: 24px;
    font-family: inherit;
    letter-spacing: -0.01em;
}

.continue-btn:hover,
.signin-btn:hover {
    background: #3a7bc8;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(74, 144, 226, 0.3);
}

.continue-btn:active,
.signin-btn:active {
    transform: translateY(0);
    box-shadow: 0 2px 8px rgba(74, 144, 226, 0.3);
}

.continue-btn:disabled,
.signin-btn:disabled {
    background: #9ca3af;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.continue-btn:disabled:hover,
.signin-btn:disabled:hover {
    background: #9ca3af;
    transform: none;
    box-shadow: none;
}

/* 加载动画 */
.loading-spinner {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: #ffffff;
    animation: spin 1s ease-in-out infinite;
    margin-right: 8px;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* 忘记密码链接 */
.forgot-password {
    text-align: right;
    margin-bottom: 24px;
}

.forgot-link {
    color: #4A90E2;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: color 0.2s ease;
}

.forgot-link:hover {
    color: #3a7bc8;
    text-decoration: underline;
}

/* 注册链接 */
.signup-link {
    text-align: center;
    font-size: 14px;
    color: #666666;
    line-height: 1.4;
}

.signup-link-text {
    color: #4A90E2;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.signup-link-text:hover {
    color: #3a7bc8;
    text-decoration: underline;
}

/* 页脚 */
.footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(26, 26, 58, 0.9);
    backdrop-filter: blur(10px);
    padding: 16px 20px;
    z-index: 10;
}

.footer-content {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.7);
    flex-wrap: wrap;
    text-align: center;
}

.separator {
    color: rgba(255, 255, 255, 0.4);
}

.footer-link {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-link:hover {
    color: #4A90E2;
    text-decoration: underline;
}

/* 响应式设计 */
@media (max-width: 480px) {
    .login-card {
        padding: 32px 24px 24px;
        margin: 20px;
        border-radius: 8px;
    }
    
    .title {
        font-size: 28px;
    }
    
    .subtitle {
        font-size: 15px;
        margin-bottom: 24px;
    }
    
    .email-input,
    .password-input,
    .continue-btn,
    .signin-btn {
        height: 44px;
        font-size: 15px;
    }
    
    .footer-content {
        font-size: 12px;
        gap: 8px;
        padding: 0 10px;
    }
    
    .footer {
        padding: 12px 16px;
    }
    
    .logo img {
        height: 56px;
        max-width: 180px;
    }
}

@media (max-width: 360px) {
    .login-card {
        padding: 24px 20px 20px;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 4px;
    }
    
    .separator {
        display: none;
    }
    
    .logo img {
        height: 48px;
        max-width: 160px;
    }
}