:root {
    --color-primary: #4f86f7;
    --color-primary-light: #70a1ff;
    --color-primary-dark: #3b74e3;
    --color-secondary: #0ea5e9;
    --color-accent: #f59e0b;
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    --color-dark: #2d3748;
    --color-gray: #718096;
    --color-light: #f8fafc;
    --color-white: #ffffff;
    --color-light-bg: rgba(79, 134, 247, 0.05);
    --gradient-primary: linear-gradient(135deg, #4f86f7, #70a1ff);
    --gradient-primary-hover: linear-gradient(135deg, #3b74e3, #5b8def);
    --gradient-secondary: linear-gradient(135deg, #0ea5e9, #3b82f6);
    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.03);
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 8px 12px rgba(0, 0, 0, 0.06);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-2xl: 28px;
    --radius-full: 9999px;
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: #f8fafc;
    color: var(--color-dark);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

::selection {
    background-color: rgba(79, 134, 247, 0.15);
    color: var(--color-primary-dark);
}

.login-container {
    width: 100%;
    max-width: 440px;
}

.login-header {
    text-align: center;
    padding: 20px 0 30px;
}

.logo {
    width: 76px;
    height: 76px;
    background: var(--color-light-bg);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    font-size: 30px;
    color: var(--color-primary);
}

.login-header h2 {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 6px;
    color: var(--color-dark);
}

.login-header p {
    color: var(--color-gray);
    font-size: 0.98rem;
}

.register-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 16px;
    padding: 8px 16px;
    background: var(--color-light-bg);
    color: var(--color-primary);
    border-radius: var(--radius-full);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition-fast);
}

.register-link:hover {
    background: rgba(79, 134, 247, 0.12);
}

.login-body {
    width: 100%;
}

.login-tabs {
    display: flex;
    background: #ffffff;
    border: 1px solid rgba(79, 134, 247, 0.1);
    border-radius: var(--radius-lg);
    padding: 6px;
    margin-bottom: 28px;
    position: relative;
}

.tab {
    flex: 1;
    text-align: center;
    padding: 12px 0;
    cursor: pointer;
    font-weight: 600;
    color: var(--color-gray);
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
    position: relative;
    z-index: 1;
}

.tab.active {
    color: var(--color-primary);
}

.tab-indicator {
    position: absolute;
    top: 6px;
    height: calc(100% - 12px);
    background: var(--color-white);
    box-shadow: var(--shadow-sm);
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}

.form-group {
    margin-bottom: 20px;
}

.input-group {
    position: relative;
}

.input-icon {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-gray);
    z-index: 2;
}

.form-control {
    width: 100%;
    padding: 16px 16px 16px 48px;
    border: 1px solid rgba(79, 134, 247, 0.15);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    background: #ffffff;
    color: var(--color-dark);
    transition: var(--transition-fast);
}

.form-control:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(79, 134, 247, 0.1);
}

.captcha-group {
    display: flex;
    gap: 14px;
}

.captcha-input {
    flex: 1;
}

.captcha-input .form-control {
    padding-left: 16px;
}

.captcha-img {
    width: 120px;
    height: 50px;
    border-radius: var(--radius-md);
    border: 1px solid rgba(79, 134, 247, 0.15);
    cursor: pointer;
    object-fit: cover;
    transition: var(--transition-fast);
}

.captcha-img:hover {
    transform: scale(1.02);
}

.code-group {
    display: flex;
    gap: 10px;
}

.code-input {
    flex: 1;
}

.btn {
    padding: 16px 24px;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-primary {
    background: var(--gradient-primary);
    color: #fff;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-block {
    width: 100%;
}

.btn-code {
    white-space: nowrap;
    padding: 16px 20px;
}

.btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none !important;
}

.form-footer {
    text-align: center;
    margin-top: 16px;
    font-size: 0.9rem;
    color: var(--color-gray);
}

.form-footer a {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 600;
}

.login-footer {
    text-align: center;
    margin-top: 36px;
    padding-top: 20px;
    border-top: 1px solid rgba(79, 134, 247, 0.1);
    font-size: 0.8rem;
    color: var(--color-gray);
}

.login-footer a {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 600;
}

/* 通知 */
.notification-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 9999;
    width: 100%;
    max-width: 380px;
}

.notification {
    background: #fff;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 18px;
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    border-left: 4px solid;
    transform: translateX(100%);
    opacity: 0;
}

.notification.show {
    transform: translateX(0);
    opacity: 1;
    animation: slideInRight 0.5s ease;
}

.notification-icon {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 14px;
    font-size: 1rem;
    flex-shrink: 0;
}

.notification-content {
    flex: 1;
}

.notification-title {
    font-weight: 600;
    margin-bottom: 4px;
    font-size: 1rem;
}

.notification-message {
    font-size: 0.9rem;
    color: var(--color-dark);
}

.notification.success {
    border-left-color: var(--color-success);
}
.notification.success .notification-icon {
    background: rgba(16, 185, 129, 0.1);
    color: var(--color-success);
}

.notification.danger {
    border-left-color: var(--color-danger);
}
.notification.danger .notification-icon {
    background: rgba(239, 68, 68, 0.1);
    color: var(--color-danger);
}

.notification.warning {
    border-left-color: var(--color-warning);
}
.notification.warning .notification-icon {
    background: rgba(245, 158, 11, 0.1);
    color: var(--color-warning);
}

.notification.info {
    border-left-color: var(--color-primary);
}
.notification.info .notification-icon {
    background: var(--color-light-bg);
    color: var(--color-primary);
}

@keyframes slideInRight {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

.loading-icon {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@media (max-width: 576px) {
    .captcha-group {
        flex-direction: column;
    }
    .captcha-img {
        width: 100%;
    }
}