/* Base Styles - Variables, Reset, Typography, Utilities */

:root {
    --color-bg: #0f0f0f;
    --color-surface: #1a1a1a;
    --color-surface-hover: #252525;
    --color-primary: #D4AF37; /* Gold */
    --color-primary-light: #f3cf55;
    --color-text: #f5f5f7;
    --color-text-muted: #a1a1aa;
    --color-border: #333;

    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
    --font-serif: 'Noto Serif SC', serif;

    --transition-base: 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Fixed background that works on mobile */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('https://kuaialliance.oss-cn-shanghai.aliyuncs.com/static/background.png');
    background-repeat: no-repeat;
    background-position: center center;
    background-size: cover;
    z-index: -1;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-serif);
    font-weight: 700;
    line-height: 1.2;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-base);
}

ul {
    list-style: none;
}

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

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Utility Classes */
.text-center { text-align: center; }

.hidden {
    display: none !important;
}

.text-muted {
    color: var(--color-text-muted);
    font-size: 0.9rem;
}

/* Animations */
.fade-in { opacity: 0; transform: translateY(0); transition: opacity 0.8s ease; }
.fade-in-up { opacity: 0; transform: translateY(30px); transition: opacity 0.8s ease, transform 0.8s ease; }
.fade-in-left { opacity: 0; transform: translateX(-30px); transition: opacity 0.8s ease, transform 0.8s ease; }
.fade-in-right { opacity: 0; transform: translateX(30px); transition: opacity 0.8s ease, transform 0.8s ease; }

.visible { opacity: 1; transform: translate(0, 0); }

.delay-100 { transition-delay: 0.1s; }
.delay-200 { transition-delay: 0.2s; }

@keyframes pulse-dot {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.8; }
}