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

:root {
    --primary-color: #3b82f6;
    --primary-light: #60a5fa;
    --primary-dark: #2563eb;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-tertiary: #9ca3af;
    --bg-page: #f7f9fa;
    --bg-card: #ffffff;
    --bg-glass: rgba(255, 255, 255, 0.75);
    --border-light: rgba(0, 0, 0, 0.06);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.08);
    --shadow-xl: 0 20px 50px rgba(0, 0, 0, 0.1);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --transition-fast: 0.15s ease;
    --transition-normal: 0.25s ease;
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

html, body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background: var(--bg-page);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    min-height: 100vh;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
    outline: none;
}

input, textarea {
    font-family: inherit;
    outline: none;
    border: none;
}

img {
    max-width: 100%;
    display: block;
}

.glass {
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
}

.hidden {
    display: none !important;
}

.fade-in {
    animation: fadeIn 0.3s ease;
}

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

.toast {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.9);
    background: rgba(0, 0, 0, 0.8);
    color: white;
    padding: 16px 28px;
    border-radius: var(--radius-md);
    font-size: 14px;
    z-index: 9999;
    opacity: 0;
    pointer-events: none;
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.toast.show {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
}

.toast.success {
    background: var(--success-color);
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid rgba(59, 130, 246, 0.15);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-tertiary);
}

.empty-state .icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.empty-state .text {
    font-size: 14px;
}