/**
 * Shared Background Styles
 * 共享背景样式 - 可被多个页面复用
 */

/* === Background Mesh (多页面使用) === */
.bg-mesh {
    background-color: #ffffff;
    background-image:
        radial-gradient(at 40% 20%, hsla(218,76%,88%,0.3) 0px, transparent 50%),
        radial-gradient(at 80% 0%, hsla(189,100%,56%,0.1) 0px, transparent 50%),
        radial-gradient(at 0% 50%, hsla(253,77%,83%,0.1) 0px, transparent 50%);
}

/* === Tech Grid Background === */
.bg-tech-grid {
    background-color: #F8FAFC;
    background-image:
        linear-gradient(rgba(148, 163, 184, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(148, 163, 184, 0.05) 1px, transparent 1px);
    background-size: 30px 30px;
}

.bg-tech-grid-dark {
    background-image:
        linear-gradient(rgba(0, 137, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 137, 255, 0.03) 1px, transparent 1px);
    background-size: 40px 40px;
}

/* === Aurora Background === */
.bg-aurora {
    background: linear-gradient(135deg, #f8fafc 0%, #e0f2fe 50%, #f0f9ff 100%);
    position: relative;
    overflow: hidden;
}

.bg-aurora::before {
    content: '';
    position: absolute;
    top: -50%; left: -50%;
    width: 200%; height: 200%;
    background:
        radial-gradient(circle at 30% 20%, rgba(0,137,255,0.08), transparent 50%),
        radial-gradient(circle at 70% 80%, rgba(123,97,255,0.08), transparent 50%),
        radial-gradient(circle at 50% 50%, rgba(0,193,222,0.06), transparent 60%);
    animation: auroraMove 30s linear infinite;
    z-index: 0;
}

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

/* === Blueprint Background === */
.blueprint-bg {
    background-image:
        linear-gradient(rgba(167, 139, 250, 0.1) 1px, transparent 1px),
        linear-gradient(90deg, rgba(167, 139, 250, 0.1) 1px, transparent 1px);
    background-size: 20px 20px;
    position: relative;
}

.blueprint-bg::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(99, 102, 241, 0.05);
}

/* === Hero Background (Dark) === */
.hero-bg-dark {
    background-color: #0F172A;
    background-image:
        radial-gradient(circle at 20% 50%, rgba(37, 99, 235, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 50%, rgba(124, 58, 237, 0.15) 0%, transparent 50%);
}

/* === Animated Gradient Background === */
.bg-animated-gradient {
    background: linear-gradient(-45deg, #667eea, #764ba2, #f093fb, #06B6D4, #667eea);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* === Noise Texture Overlay === */
.noise-overlay::after {
    content: '';
    position: absolute;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
    opacity: 0.03;
    pointer-events: none;
    z-index: 1;
}

/* === Floating Orbs === */
.orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(60px);
    opacity: 0.6;
    animation: orbFloat 20s ease-in-out infinite;
}

@keyframes orbFloat {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(50px, -50px) scale(1.1); }
    50% { transform: translate(-30px, 30px) scale(0.95); }
    75% { transform: translate(40px, 20px) scale(1.05); }
}

/* === Surface Colors === */
.bg-surface { background-color: #F8FAFC; }
.bg-surface-dark { background-color: #0F172A; }