/* Design System Variables (Default Light Theme) */
:root {
    --bg-color: #ffffff;
    --text-color: #000000;
    --border-color: #e0e0e0;
    --accent-bg: #fafafa;
    --hover-bg: #f5f5f5;
    --muted-text: #666666;
    --light-muted: #888888;
    --accent-green: #008000;
    --error-red: #d93025;
}

/* Explicit Dark Theme Variable Mapping */
body.dark-mode {
    --bg-color: #121212;
    --text-color: #e0e0e0;
    --border-color: #2d2d2d;
    --accent-bg: #1a1a1a;
    --hover-bg: #242424;
    --muted-text: #a0a0a0;
    --light-muted: #666666;
    --accent-green: #00b300;
    --error-red: #ff4d4d;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Header Navigation */
header {
    border-bottom: 1px solid var(--border-color);
    padding: 1.5rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: -0.05em;
    text-transform: uppercase;
}

.nav-links {
    display: flex;
    align-items: center;
}

.nav-links a {
    color: var(--muted-text);
    text-decoration: none;
    margin-left: 1.5rem;
    font-size: 0.9rem;
    transition: color 0.2s ease;
}

.nav-links a:hover, .nav-links a.active-nav {
    color: var(--text-color);
}

.theme-toggle {
    background: none;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 0.4rem 0.8rem;
    font-size: 0.8rem;
    cursor: pointer;
    margin-left: 1.5rem;
    font-weight: 600;
}

/* Main Content Layout */
main {
    max-width: 850px;
    margin: 3rem auto;
    padding: 0 1.5rem;
}

.hero-section {
    margin-bottom: 2.5rem;
    text-align: center;
}

.hero-section h1 {
    font-size: 2.4rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -0.03em;
}

.hero-section p {
    color: var(--muted-text);
    font-size: 1.1rem;
}

/* Advanced Configuration Grid */
.controls-container {
    display: grid;
    grid-template-columns: 2fr 2fr 1fr;
    gap: 0.75rem;
    margin-bottom: 2rem;
}

.search-input, .filter-select, .action-btn {
    width: 100%;
    padding: 0.8rem 1rem;
    font-size: 0.95rem;
    background-color: var(--bg-color);
    color: var(--text-color);
    border: 2px solid var(--text-color);
    outline: none;
}

.search-input:focus {
    background-color: var(--accent-bg);
}

.filter-select {
    cursor: pointer;
}

.action-btn {
    background: var(--text-color);
    color: var(--bg-color);
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s;
    white-space: nowrap;
}

.action-btn:hover {
    opacity: 0.85;
}

.search-stats {
    grid-column: span 3;
    font-size: 0.85rem;
    color: var(--light-muted);
    text-align: right;
    margin-top: 0.2rem;
}

/* Managers Directory Array */
.managers-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 0.75rem;
    list-style: none;
}

.manager-card {
    background: var(--bg-color);
    border: 1px solid var(--border-color);
    padding: 1rem;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.2s ease;
}

.manager-card:hover {
    border-color: var(--text-color);
    background-color: var(--hover-bg);
    cursor: pointer;
}

.highlight {
    background-color: var(--border-color);
    font-weight: 700;
    color: var(--text-color);
}

.no-results {
    text-align: center;
    padding: 3rem;
    color: var(--light-muted);
    border: 1px dashed var(--border-color);
    display: none;
}

/* Core Modals Architecture */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-card {
    background: var(--bg-color);
    border: 2px solid var(--text-color);
    width: 90%;
    max-width: 450px;
    padding: 2rem;
    position: relative;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    color: var(--text-color);
}

.close-btn {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    font-weight: bold;
    color: var(--text-color);
}

.loader-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2.5rem 1rem;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--text-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin-bottom: 1.2rem;
}

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

/* Analytics Presentation Layer */
.profile-content h2 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.profile-rank {
    display: inline-block;
    background: var(--text-color);
    color: var(--bg-color);
    padding: 0.2rem 0.6rem;
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.profile-stat-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    padding: 0.7rem 0;
    font-size: 0.95rem;
}

.profile-stat-row.vertical {
    flex-direction: column;
    align-items: stretch;
}

.stat-header-split {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.4rem;
}

.profile-stat-label {
    color: var(--muted-text);
}

.profile-stat-value {
    font-weight: 600;
}

/* Custom Horizontal Progress Tracking Visualization */
.progress-bar-container {
    width: 100%;
    background-color: var(--border-color);
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    background-color: var(--text-color);
    width: 0%;
    transition: width 0.6s ease-out;
}

.ref-input-container {
    margin-top: 1.5rem;
    padding-top: 1rem;
    border-top: 1px dashed var(--border-color);
}

.ref-input-container label {
    display: block;
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 0.4rem;
    text-transform: uppercase;
    color: var(--muted-text);
}

.ref-input {
    width: 100%;
    padding: 0.6rem;
    border: 1px solid var(--border-color);
    background-color: var(--bg-color);
    color: var(--text-color);
    font-size: 0.9rem;
    outline: none;
}

.ref-input:focus {
    border-color: var(--text-color);
}

.ref-error {
    color: var(--error-red);
    font-size: 0.8rem;
    margin-top: 0.4rem;
    display: none;
    font-weight: 500;
}

/* Assignment Workspace State */
.project-page {
    display: none;
    max-width: 900px;
    margin: 3rem auto;
    padding: 0 1.5rem;
}

.back-btn {
    background: none;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    margin-bottom: 2rem;
    transition: all 0.2s ease;
}

.back-btn:hover {
    background: var(--text-color);
    color: var(--bg-color);
}

.project-section-title {
    font-size: 1.3rem;
    border-bottom: 2px solid var(--text-color);
    padding-bottom: 0.5rem;
    margin: 2rem 0 1rem 0;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.project-card {
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    margin-bottom: 1rem;
    background: var(--bg-color);
    position: relative;
}

.project-card.active-project {
    border: 2px solid var(--text-color);
    background: var(--accent-bg);
}

.project-card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
}

.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.badge-active {
    background: var(--accent-green);
    color: #ffffff;
    font-size: 0.75rem;
    padding: 0.1rem 0.4rem;
    font-weight: bold;
    text-transform: uppercase;
    margin-left: 0.5rem;
}

.expand-indicator {
    font-size: 1rem;
    color: var(--muted-text);
    margin-left: auto;
    font-weight: bold;
}

.expandable-details {
    display: none;
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px dashed var(--border-color);
}

.detail-header {
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--text-color);
    margin-bottom: 0.4rem;
    margin-top: 1rem;
}

.detail-body {
    font-size: 0.95rem;
    color: var(--muted-text);
    margin-bottom: 0.8rem;
}

.credentials-box {
    background: var(--hover-bg);
    border: 1px dashed var(--border-color);
    padding: 1rem;
    margin: 1.2rem 0;
    font-family: monospace;
    font-size: 0.9rem;
}

.cta-btn {
    display: inline-block;
    background: var(--text-color);
    color: var(--bg-color);
    border: none;
    padding: 0.8rem 1.5rem;
    font-size: 0.95rem;
    font-weight: 700;
    cursor: pointer;
    text-decoration: none;
    text-align: center;
    width: 100%;
    transition: opacity 0.2s ease;
}

.cta-btn:hover {
    opacity: 0.9;
}

/* Responsive Scaling Overrides */
@media(max-width: 650px) {
    .controls-container {
        grid-template-columns: 1fr;
    }
    .search-stats {
        grid-column: span 1;
        text-align: left;
    }
}