:root {
    --strata-dark: #1e1a17;
    --strata-clay: #2a221f;
    --strata-border: #5c4d44;
    --text-cream: #ede6de;
    --text-muted: #9c8e85;
    --border-line: rgba(92, 77, 68, 0.3);
}
body {
    background-color: var(--strata-dark);
    background-image: repeating-linear-gradient(180deg, var(--strata-dark), var(--strata-dark) 40px, #181512 40px, #181512 80px);
    color: var(--text-cream);
    font-family: "PingFang SC", "Microsoft YaHei", "SimSun", serif;
    margin: 0;
    padding: 0;
}
.strata-header {
    background: var(--strata-clay);
    border-bottom: 2px solid var(--strata-border);
    height: 65px;
    position: sticky;
    top: 0;
    z-index: 999;
}
.strata-logo img {
    height: 38px;
    margin-top: 13px;
}
.nav-link {
    color: var(--text-cream) !important;
    font-weight: bold;
    font-size: 13px;
}
.nav-link:hover {
    color: var(--text-muted) !important;
}
.two-column-split {
    display: flex;
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 15px 100px 15px;
    gap: 30px;
    box-sizing: border-box;
}
.split-left {
    width: 40%;
    flex-shrink: 0;
}
.split-right {
    width: 60%;
    flex-grow: 1;
}
.strata-box {
    background: var(--strata-clay);
    border: 2px solid var(--strata-border);
    padding: 25px;
    box-sizing: border-box;
}
.strata-card {
    background: var(--strata-clay);
    border: 1px solid var(--strata-border);
    padding: 25px;
    margin-bottom: 20px;
    transition: all 0.3s;
}
.strata-card:hover {
    border-color: var(--text-cream);
    box-shadow: 0 0 15px rgba(92, 77, 68, 0.2);
}
.strata-btn {
    background: var(--strata-dark);
    color: var(--text-cream) !important;
    border: 1px solid var(--strata-border);
    padding: 8px 24px;
    font-weight: bold;
    cursor: pointer;
    display: inline-block;
    transition: all 0.2s;
}
.strata-btn:hover {
    background: var(--text-cream);
    color: var(--strata-dark) !important;
}
.sidebar-link {
    display: block;
    color: var(--text-cream);
    padding: 12px 15px;
    border-bottom: 1px solid var(--border-line);
    text-decoration: none;
    font-size: 13px;
}
.sidebar-link:hover {
    background: var(--strata-dark);
    color: var(--text-cream);
}
@media (max-width: 768px) {
    .two-column-split {
        flex-direction: column;
    }
    .split-left, .split-right {
        width: 100%;
    }
}