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

html { scroll-behavior: smooth; }

body {
    font-family: 'Noto Sans SC', sans-serif;
    background: var(--darker);
    color: var(--light);
    overflow-x: hidden;
    line-height: 1.7;
}

/* ===== 粒子背景 ===== */
#particles-canvas {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* ===== 通用 ===== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 5%;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}
.section-tag {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.4rem 1.2rem;
    background: rgba(79,70,229,0.1);
    border: 1px solid rgba(79,70,229,0.25);
    border-radius: 50px;
    font-size: 0.8rem;
    color: var(--primary-light);
    margin-bottom: 1rem;
    letter-spacing: 1px;
}
.section-title {
    font-size: clamp(1.8rem, 3.5vw, 2.8rem);
    font-weight: 800;
    margin-bottom: 0.75rem;
    line-height: 1.2;
}
.section-title .gradient-text {
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.section-desc {
    color: var(--gray-400);
    max-width: 580px;
    margin: 0 auto;
    font-size: 1rem;
}

/* ===== 滚动条 ===== */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--darker); }
::-webkit-scrollbar-thumb {
    background: var(--primary);
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover { background: var(--primary-light); }