/* CSS Variables - Light Theme */
:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f6f8fa;
    --bg-tertiary: #eef1f5;
    --bg-card: #f6f8fa;
    --bg-hover: #e1e4e8;
    --text-primary: #1f2328;
    --text-secondary: #656d76;
    --text-muted: #8b949e;
    --border-color: #d0d7de;
    --border-light: #d8dee4;
    --accent-blue: #0969da;
    --accent-green: #1a7f37;
    --accent-red: #cf222e;
    --accent-orange: #9a6700;
    --accent-purple: #8250df;
    --shadow: 0 1px 3px rgba(31,35,40,0.08);
    --shadow-lg: 0 4px 12px rgba(31,35,40,0.12);
    --radius: 4px;
    --radius-lg: 6px;
    --header-height: 52px;
    --panel-width: 420px;
    --transition: 0.2s ease;
}

/* Reset */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 14px;
    color: var(--text-primary);
    background: var(--bg-primary);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
}

/* Layout */
#header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-height);
    padding: 0 20px;
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
    z-index: 100;
}

.header-left { display: flex; align-items: center; gap: 12px; }
.header-center { flex: 1; max-width: 400px; margin: 0 24px; }
.header-right { display: flex; align-items: center; gap: 4px; }

.logo {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
}

#app {
    display: flex;
    height: calc(100vh - var(--header-height));
    overflow: hidden;
}

/* Nav Tabs in Header */
.nav-tab {
    padding: 6px 16px;
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 13px;
    cursor: pointer;
    transition: color var(--transition);
}
.nav-tab:hover { color: var(--text-primary); }
.nav-tab.active {
    color: var(--text-primary);
    font-weight: 600;
}

/* View Containers */
.view-container {
    flex: 1;
    overflow-y: auto;
    padding: 24px 32px;
    scrollbar-width: thin;
    scrollbar-color: var(--bg-hover) transparent;
}
.view-container.hidden { display: none; }

/* Section */
.section-divider {
    height: 1px;
    background: var(--border-color);
    margin: 32px 0;
}
.section-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 16px;
    letter-spacing: 1px;
}

/* Search */
.search-container { position: relative; }
#search-input {
    width: 100%;
    padding: 8px 12px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    color: var(--text-primary);
    font-size: 13px;
    outline: none;
    transition: border-color var(--transition);
}
#search-input:focus { border-color: var(--accent-blue); }
#search-input::placeholder { color: var(--text-muted); }

.search-dropdown {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    max-height: 320px;
    overflow-y: auto;
    z-index: 200;
    box-shadow: var(--shadow-lg);
}
.search-result-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    cursor: pointer;
    font-size: 13px;
    transition: background var(--transition);
}
.search-result-item:hover,
.search-result-item.active { background: var(--bg-hover); }
.search-result-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    flex-shrink: 0;
}
.search-result-label { flex: 1; }
.search-result-type { color: var(--text-muted); font-size: 11px; }
.search-result-item mark { background: rgba(88,166,255,0.3); color: var(--text-primary); border-radius: 2px; padding: 0 2px; }

/* Hidden */
.hidden { display: none !important; }

/* Responsive */
@media (max-width: 900px) {
    .header-center { margin: 0 12px; }
    .nav-tab { padding: 6px 10px; font-size: 12px; }
    .view-container { padding: 16px; }
}
@media (max-width: 600px) {
    .nav-tab { padding: 4px 8px; font-size: 11px; }
    .logo { font-size: 14px; }
}