:root {
    --bg-color: #f8fafc;
    --panel-bg: #ffffff;
    --text-color: #1e293b;
    --accent-color: #3b82f6;
    --border-color: #cbd5e1;
    --success-color: #10b981;
    --danger-color: #ef4444;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0;
    height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    padding: 20px;
    height: 100%;
    box-sizing: border-box;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--border-color);
}

h1 {
    margin: 0;
    font-size: 24px;
    color: #1e293b;
    font-weight: 700;
}

.grid-layout {
    display: grid;
    grid-template-columns: 1fr 3.5fr 1fr;
    gap: 20px;
    height: calc(100% - 70px);
}

.panel {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.card {
    background-color: var(--panel-bg);
    border-radius: 8px;
    padding: 15px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    flex: 1;
    display: flex;
    flex-direction: column;
    border: 1px solid #e2e8f0;
}

.card h2 {
    margin-top: 0;
    font-size: 16px;
    color: #475569;
    margin-bottom: 10px;
    font-weight: 600;
    border-bottom: 1px solid #f1f5f9;
    padding-bottom: 8px;
}

.chart-container {
    flex: 1;
    min-height: 200px;
}

.search-box {
    position: relative;
    margin-bottom: 20px;
}

#studentSearch {
    width: 100%;
    padding: 12px;
    background-color: var(--panel-bg);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-color);
    font-size: 16px;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.search-results {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--panel-bg);
    border: 1px solid var(--border-color);
    border-top: none;
    border-radius: 0 0 6px 6px;
    max-height: 200px;
    overflow-y: auto;
    z-index: 100;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.search-item {
    padding: 10px;
    cursor: pointer;
    border-bottom: 1px solid #f1f5f9;
}

.search-item:hover {
    background-color: #f1f5f9;
}

.student-detail {
    background-color: var(--panel-bg);
    padding: 20px;
    border-radius: 8px;
    flex: 1;
    display: flex;
    flex-direction: column;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    border: 1px solid #e2e8f0;
}

.student-header {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 20px;
}

.badge {
    background-color: var(--accent-color);
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 14px;
    color: white;
    font-weight: 600;
}

.stats-cards {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 10px;
    margin-bottom: 20px;
}

.stat-card {
    background-color: #f8fafc;
    padding: 10px;
    border-radius: 6px;
    text-align: center;
    border: 1px solid #e2e8f0;
}

.stat-card h3 {
    margin: 0;
    font-size: 12px;
    color: #64748b;
    font-weight: 600;
}

.stat-card p {
    margin: 5px 0 0;
    font-size: 18px;
    font-weight: bold;
    color: #0f172a;
}

.rank-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.rank-item {
    display: flex;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid #f1f5f9;
}

.rank-item span:last-child {
    font-weight: bold;
}

.positive { color: var(--danger-color); font-weight: bold; } /* Rise = Red */
.negative { color: var(--success-color); font-weight: bold; } /* Fall = Green */

.welcome-msg {
    text-align: center;
    padding-top: 100px;
    color: #64748b;
}

.large-card {
    flex: 2;
    margin-top: 20px;
    border: none;
    box-shadow: none;
    padding: 0;
}