:root {
    --primary-red: #de2910;
    --primary-gold: #ffde00;
    --ring-blue: #1e88e5;
    --domain-green: #43a047;
    --field-gold: #ffa000;
    --polynomial-purple: #8e24aa;
    --bg-color: #fdfbf7;
    --text-dark: #2c3e50;
    --text-light: #596b7e;
    --glass-bg: rgba(255, 255, 255, 0.92);
    --glass-border: rgba(255, 255, 255, 0.5);
    --shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.15);
    --font-title: 'Ma Shan Zheng', cursive;
    --font-body: 'Outfit', sans-serif;
    --font-serif: 'Noto Serif SC', serif;
    --font-mono: 'JetBrains Mono', monospace;
}

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

body {
    background-color: var(--bg-color);
    background-image:
        radial-gradient(circle at 10% 20%, rgba(222, 41, 16, 0.03) 0%, transparent 20%),
        radial-gradient(circle at 90% 80%, rgba(67, 160, 71, 0.03) 0%, transparent 20%);
    color: var(--text-dark);
    font-family: var(--font-body);
    min-height: 100vh;
}

.app-container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 20px;
}

/* ===== Header ===== */
.main-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 35px;
    background: var(--glass-bg);
    backdrop-filter: blur(15px);
    border-radius: 16px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
    border: 1px solid var(--glass-border);
}

.header-content h1 {
    font-family: var(--font-serif);
    font-size: 1.6rem;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.header-content .highlight {
    color: var(--primary-red);
    font-family: var(--font-title);
    font-size: 2rem;
    margin-left: 10px;
}

.subtitle {
    font-family: var(--font-body);
    color: var(--text-light);
    font-size: 0.85rem;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.ideology-badge {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 24px;
    background: linear-gradient(135deg, var(--ring-blue), var(--domain-green));
    color: white;
    border-radius: 25px;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(30, 136, 229, 0.3);
}

.badge-icon {
    font-size: 1.3rem;
}

/* ===== Main Stage ===== */
.main-stage {
    display: grid;
    grid-template-columns: 280px 1fr 320px;
    gap: 20px;
    min-height: 600px;
}

.left-panel,
.right-panel,
.center-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(15px);
    border-radius: 14px;
    box-shadow: var(--shadow);
    border: 1px solid var(--glass-border);
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

/* ===== Panel Sections ===== */
.panel-section {
    background: rgba(255, 255, 255, 0.5);
    border-radius: 12px;
    padding: 18px;
}

.panel-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--primary-gold);
}

.panel-icon {
    font-size: 1.4rem;
}

.panel-header h3 {
    font-size: 1.05rem;
    color: var(--primary-red);
    font-weight: 700;
}

/* ===== Navigation ===== */
.op-nav {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 15px;
    background: white;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.2s;
    text-align: left;
}

.nav-btn:hover {
    border-color: var(--ring-blue);
    transform: translateX(5px);
}

.nav-btn.active {
    background: linear-gradient(135deg, #e3f2fd, #f1f8e9);
    border-color: var(--ring-blue);
    box-shadow: 0 4px 12px rgba(30, 136, 229, 0.2);
}

.nav-icon {
    font-size: 1.5rem;
}

.nav-info {
    display: flex;
    flex-direction: column;
}

.nav-title {
    font-weight: 700;
    font-size: 0.95rem;
    color: var(--text-dark);
}

.nav-desc {
    font-size: 0.75rem;
    color: var(--text-light);
}

/* ===== Instructions ===== */
.instruction-text {
    font-size: 0.9rem;
    line-height: 1.6;
    color: var(--text-dark);
}

.instruction-text ul {
    padding-left: 20px;
    margin-top: 10px;
}

.instruction-text li {
    margin-bottom: 8px;
}

/* ===== Content Area ===== */
.canvas-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.canvas-header h2 {
    font-family: var(--font-title);
    font-size: 1.8rem;
    color: var(--primary-red);
}

.canvas-controls {
    display: flex;
    gap: 15px;
    align-items: center;
}

.control-label {
    font-size: 0.9rem;
    color: var(--text-dark);
    margin-right: 8px;
}

.control-input {
    padding: 8px 12px;
    border: 2px solid #d9d9d9;
    border-radius: 6px;
    font-size: 0.95rem;
    font-family: var(--font-mono);
    transition: border-color 0.2s;
}

.control-input:focus {
    outline: none;
    border-color: var(--ring-blue);
}

.control-btn {
    padding: 8px 16px;
    background: var(--ring-blue);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
    transition: background 0.2s;
}

.control-btn:hover {
    background: #1565c0;
}

.control-btn.secondary {
    background: white;
    border: 1px solid #d9d9d9;
    color: var(--text-dark);
}

.control-btn.secondary:hover {
    border-color: var(--ring-blue);
    color: var(--ring-blue);
}

.content-container {
    flex: 1;
    background: white;
    border-radius: 12px;
    padding: 20px;
    box-shadow: inset 0 2px 8px rgba(0, 0, 0, 0.05);
    overflow: auto;
}

/* ===== Cayley Table ===== */
.cayley-table-wrapper {
    margin-bottom: 30px;
}

.cayley-table-wrapper h3 {
    font-size: 1.1rem;
    color: var(--primary-red);
    margin-bottom: 15px;
}

.cayley-table {
    border-collapse: collapse;
    margin: 0 auto;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.cayley-table th,
.cayley-table td {
    width: 40px;
    height: 40px;
    text-align: center;
    border: 1px solid #e0e0e0;
    font-family: var(--font-mono);
    font-size: 0.9rem;
}

.cayley-table th {
    background: linear-gradient(135deg, #e3f2fd, #f1f8e9);
    font-weight: 700;
    color: var(--text-dark);
}

.cayley-table td {
    background: white;
    cursor: pointer;
    transition: all 0.2s;
}

.cayley-table td:hover {
    background: #fff9c4;
    transform: scale(1.1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.cayley-table td.zero-divisor {
    background: #ffebee;
    color: #c62828;
    font-weight: 700;
}

.cayley-table td.unit {
    background: #e8f5e9;
    color: #2e7d32;
    font-weight: 700;
}

.cayley-table td.zero {
    background: #f5f5f5;
    color: #9e9e9e;
}

/* ===== Polynomial Display ===== */
.polynomial-display {
    background: #f9f9f9;
    padding: 20px;
    border-radius: 8px;
    margin: 15px 0;
    font-size: 1.2rem;
    text-align: center;
    font-family: var(--font-mono);
    border: 2px solid var(--polynomial-purple);
}

.polynomial-input {
    display: flex;
    gap: 15px;
    align-items: center;
    margin: 15px 0;
    flex-wrap: wrap;
}

.coefficient-input {
    width: 60px;
    padding: 8px;
    border: 2px solid #d9d9d9;
    border-radius: 4px;
    text-align: center;
    font-family: var(--font-mono);
}

/* ===== Hierarchy Diagram ===== */
.hierarchy-diagram {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 30px;
    padding: 30px;
}

.hierarchy-level {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
    position: relative;
}

.hierarchy-node {
    background: white;
    padding: 20px 40px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border: 3px solid var(--ring-blue);
    cursor: pointer;
    transition: all 0.3s;
    text-align: center;
}

.hierarchy-node:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.hierarchy-node.active {
    background: linear-gradient(135deg, #e3f2fd, #f1f8e9);
    border-color: var(--field-gold);
}

.hierarchy-node h4 {
    font-size: 1.2rem;
    color: var(--primary-red);
    margin-bottom: 8px;
}

.hierarchy-node p {
    font-size: 0.85rem;
    color: var(--text-light);
}

.hierarchy-arrow {
    width: 3px;
    height: 30px;
    background: linear-gradient(to bottom, var(--ring-blue), var(--domain-green));
    position: relative;
}

.hierarchy-arrow::after {
    content: '▼';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--domain-green);
    font-size: 1.2rem;
}

/* ===== Ideology Box ===== */
.ideology-box {
    background: linear-gradient(135deg, #fff5f5, #ffffff);
    border: 2px solid var(--primary-red);
    border-radius: 12px;
    padding: 20px;
    margin-top: 20px;
}

.ideology-title {
    font-weight: 700;
    color: var(--primary-red);
    margin-bottom: 10px;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.ideology-content {
    font-size: 0.95rem;
    line-height: 1.7;
    color: var(--text-dark);
    text-align: justify;
}

/* ===== Info Content ===== */
.info-content {
    font-size: 0.9rem;
    line-height: 1.6;
    color: var(--text-dark);
}

.definition-item {
    background: #f9f9f9;
    padding: 12px;
    border-radius: 6px;
    margin-bottom: 10px;
    border-left: 3px solid var(--ring-blue);
}

.definition-item strong {
    color: var(--primary-red);
}

/* ===== Properties List ===== */
.properties-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.property-badge {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px;
    background: white;
    border-radius: 6px;
    border: 1px solid #f0f0f0;
}

.property-label {
    color: var(--text-dark);
    font-size: 0.9rem;
}

.property-status {
    font-weight: 700;
    font-family: var(--font-mono);
}

.property-status.true {
    color: var(--domain-green);
}

.property-status.false {
    color: #d32f2f;
}

/* ===== Responsive ===== */
@media (max-width: 1200px) {
    .main-stage {
        grid-template-columns: 1fr;
    }
}