:root {
    --color-primary: #0F172A;
    --color-on-primary: #FFFFFF;
    --color-secondary: #1E293B;
    --color-accent: #22C55E;
    --color-background: #020617;
    --color-foreground: #F8FAFC;
    --color-muted: #1A1E2F;
    --color-border: #334155;
    --color-destructive: #EF4444;
    --color-warning: #F59E0B;
    --color-highlight: #3B82F6;
    --color-on-destructive: #FFFFFF;
    
    --font-heading: 'Lexend', sans-serif;
    --font-body: 'Be Vietnam Pro', sans-serif;
    
    --glass-bg: rgba(15, 23, 42, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    
    --transition-speed: 0.3s;
}

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

body {
    background: radial-gradient(circle at top right, #0F172A, #020617);
    color: var(--color-foreground);
    font-family: var(--font-body);
    overflow-x: hidden;
    min-height: 100vh;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 6px;
}
::-webkit-scrollbar-track {
    background: var(--color-background);
}
::-webkit-scrollbar-thumb {
    background: var(--color-border);
    border-radius: 10px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--color-accent);
}

.dashboard-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar Styling */
.sidebar {
    width: 280px;
    background-color: var(--color-primary);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    padding: 2rem;
    position: fixed;
    height: 100vh;
    z-index: 10;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--color-accent);
    margin-bottom: 3rem;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: 8px;
    margin-bottom: 8px;
    cursor: pointer;
    transition: var(--transition-speed);
    color: #94A3B8;
}

.nav-item:hover, .nav-item.active {
    background-color: var(--color-secondary);
    color: var(--color-foreground);
}

.nav-item.active {
    border-left: 3px solid var(--color-accent);
}

.upload-section {
    margin-top: auto;
}

.dropzone {
    border: 2px dashed var(--color-border);
    border-radius: 12px;
    padding: 1.5rem;
    text-align: center;
    transition: var(--transition-speed);
    cursor: pointer;
}

.dropzone:hover {
    border-color: var(--color-accent);
    background-color: rgba(34, 197, 94, 0.05);
}

.dropzone p {
    font-size: 0.875rem;
    margin-top: 10px;
}

.dropzone span {
    color: #94A3B8;
    font-size: 0.75rem;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--color-muted);
    padding: 12px;
    border-radius: 8px;
    margin-top: 10px;
    font-size: 0.813rem;
}

/* Main Content Area */
.main-content {
    flex: 1;
    margin-left: 280px;
    padding: 2rem;
}

.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 2rem;
}

.page-title h1 {
    font-family: var(--font-heading);
    font-size: 1.75rem;
    margin-bottom: 4px;
}

.page-title p {
    color: #94A3B8;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

.btn {
    padding: 10px 20px;
    border-radius: 8px;
    border: none;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition-speed);
}

.btn-primary {
    background-color: var(--color-accent);
    color: white;
}

.btn-primary:hover {
    filter: brightness(1.1);
}

.profile img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid var(--color-border);
}

.badge-accent {
    background: rgba(34, 197, 94, 0.1);
    color: var(--color-accent);
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.badge-highlight {
    background: rgba(59, 130, 246, 0.1);
    color: var(--color-highlight);
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    border: 1px solid rgba(59, 130, 246, 0.2);
}

/* KPI Cards */
.kpi-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.kpi-card {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 1.5rem;
    border-radius: 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border: 1px solid var(--glass-border);
    transition: all var(--transition-speed);
}

.kpi-card:hover {
    transform: translateY(-5px);
    border-color: var(--color-accent);
    box-shadow: 0 10px 30px -10px rgba(34, 197, 94, 0.2);
}

.kpi-info .label {
    display: block;
    font-size: 0.813rem;
    color: #94A3B8;
    margin-bottom: 8px;
}

.kpi-info h2 {
    font-family: var(--font-heading);
    font-size: 2rem;
}

.kpi-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-muted);
}

.kpi-icon.positive { background-color: rgba(34, 197, 94, 0.1); color: var(--color-accent); }
.kpi-icon.highlight { background-color: rgba(59, 130, 246, 0.1); color: var(--color-highlight); }
.kpi-icon.warning { background-color: rgba(245, 158, 11, 0.1); color: var(--color-warning); }

/* Visualization Grid */
.viz-grid {
    display: grid;
    grid-template-columns: 3fr 2fr;
    gap: 1.5rem;
}

.viz-card {
    background-color: var(--color-secondary);
    border-radius: 16px;
    border: 1px solid var(--color-border);
    padding: 1.5rem;
    min-height: 400px;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.card-header h3 {
    font-family: var(--font-heading);
}

.filters input {
    background-color: var(--color-muted);
    border: 1px solid var(--color-border);
    padding: 8px 16px;
    border-radius: 8px;
    color: white;
    outline: none;
}

/* Table Styling */
.table-wrapper {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
}

th {
    text-align: left;
    padding: 12px;
    color: #94A3B8;
    background-color: rgba(255, 255, 255, 0.05);
    border-bottom: 2px solid var(--color-border);
}

td {
    padding: 12px;
    border-bottom: 1px solid var(--color-border);
}

tbody tr:hover {
    background-color: rgba(255, 255, 255, 0.02);
}

.empty-state {
    text-align: center;
    padding: 3rem;
    color: #94A3B8;
}

/* Inline Editing & Mocking */
.editable {
    background-color: rgba(34, 197, 94, 0.05);
    border: 1px solid transparent;
    border-radius: 4px;
    padding: 2px 8px;
    cursor: text;
    transition: var(--transition-speed);
}

.editable:focus {
    background-color: var(--color-muted);
    border-color: var(--color-accent);
    outline: none;
}

.tab-content {
    display: none;
    animation: fadeIn 0.3s ease-in-out;
}

.tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.full-width {
    grid-column: 1 / -1;
}

.save-status {
    font-size: 0.75rem;
    color: var(--color-accent);
    background: rgba(34, 197, 94, 0.1);
    padding: 4px 12px;
    border-radius: 20px;
}

.bulk-actions {
    display: flex;
    align-items: center;
    gap: 15px;
    font-size: 0.875rem;
    color: #94A3B8;
}

.bulk-input-group {
    display: flex;
    gap: 8px;
}

.bulk-input-group input {
    width: 60px;
    background: var(--color-muted);
    border: 1px solid var(--color-border);
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    outline: none;
}

.btn-sm {
    padding: 4px 12px;
    font-size: 0.75rem;
    min-width: 80px; /* Fixed width for consistency */
    text-align: center;
}

.exception-row {
    background-color: rgba(239, 68, 68, 0.02) !important;
    opacity: 0.8;
}

.badge-exception {
    background-color: var(--color-destructive);
    color: white;
    font-size: 10px;
    padding: 2px 6px;
    border-radius: 4px;
    margin-left: 8px;
    text-transform: uppercase;
    font-weight: 700;
}

.btn-mock {
    background: none;
    border: 1px solid var(--color-border);
    color: #94A3B8;
    padding: 4px 8px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.75rem;
    min-width: 80px; /* Fixed width */
    text-align: center;
}

.btn-mock.active {
    background-color: var(--color-highlight);
    color: white;
    border-color: var(--color-highlight);
}

.action-group {
    display: flex;
    align-items: center;
    gap: 12px;
}

.btn-icon-delete {
    background: none;
    border: none;
    color: var(--color-destructive);
    font-size: 1.25rem;
    cursor: pointer;
    line-height: 1;
    padding: 0 4px;
    opacity: 0.7;
    transition: opacity 0.2s;
}

.btn-icon-delete:hover {
    opacity: 1;
}

/* Chart Canvas */
.chart-container canvas {
    max-height: 350px;
}

.title-with-help {
    display: flex;
    align-items: center;
    gap: 15px;
}

.btn-help {
    background: none;
    border: none;
    color: #94A3B8;
    cursor: pointer;
    display: flex;
    align-items: center;
    transition: color 0.2s;
}

.btn-help:hover {
    color: var(--color-accent);
}

/* Modal Styling */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    animation: fadeIn 0.1s ease-out;
}

.modal-content {
    background: var(--color-secondary);
    border: 1px solid var(--color-border);
    width: 90%;
    max-width: 600px;
    max-height: 85vh;
    border-radius: 20px;
    padding: 30px;
    overflow-y: auto;
    box-shadow: 0 20px 50px rgba(0,0,0,0.5);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 15px;
}

.modal-header h2 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.25rem;
    color: var(--color-accent);
}

.btn-close {
    background: none;
    border: none;
    color: #94A3B8;
    font-size: 2rem;
    cursor: pointer;
}

.help-section {
    margin-bottom: 25px;
}

.help-section h3 {
    font-size: 1rem;
    margin-bottom: 10px;
    color: var(--color-foreground);
    font-family: var(--font-heading);
}

.help-section p, .help-section li {
    font-size: 0.875rem;
    color: #94A3B8;
    line-height: 1.6;
}

.help-section ul, .help-section ol {
    margin-left: 20px;
    margin-top: 5px;
}

.hidden { display: none !important; }

.settings-group {
    margin-bottom: 25px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.settings-select {
    background: var(--color-muted);
    border: 1px solid var(--color-border);
    color: white;
    padding: 8px 12px;
    border-radius: 8px;
    outline: none;
    cursor: pointer;
}

.settings-table input {
    width: 100%;
    background: rgba(0, 0, 0, 0.2); /* Tối hơn để tạo độ sâu */
    border: 1px solid var(--color-border);
    color: white;
    padding: 6px 10px;
    border-radius: 6px;
    transition: all 0.2s;
    cursor: pointer;
}

.settings-table input:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: #475569;
}

.settings-table input:focus {
    background: var(--color-muted);
    border-color: var(--color-accent);
    outline: none;
    cursor: text;
    box-shadow: 0 0 0 2px rgba(34, 197, 94, 0.2);
}

.settings-actions {
    margin-top: 30px;
    display: flex;
    justify-content: flex-end;
}

.btn-icon-add {
    background: rgba(34, 197, 94, 0.1);
    color: var(--color-accent);
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.inline-input {
    width: 80px !important;
}

/* Target GPA Calculator Card */
.target-calculator {
    grid-column: span 1;
    min-width: 280px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(34, 197, 94, 0.05));
    border-left: 4px solid var(--color-highlight);
}

.target-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.small-icon {
    width: 16px;
    height: 16px;
    color: var(--color-highlight);
    opacity: 0.7;
}

.target-input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

.target-input-group input {
    flex: 1;
    background: var(--color-muted);
    border: 1px solid var(--color-border);
    color: white;
    padding: 8px 12px;
    border-radius: 8px;
    outline: none;
    font-weight: 600;
}

.target-input-group input:focus {
    border-color: var(--color-highlight);
}

.btn-accent {
    background-color: var(--color-highlight);
    color: white;
}

.target-result {
    font-size: 0.875rem;
    color: #F8FAFC;
    padding: 10px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    border: 1px dashed var(--color-border);
    animation: slideIn 0.3s ease-out;
}

.target-result strong {
    color: var(--color-accent);
    font-size: 1.125rem;
}

.btn-text {
    background: none;
    border: none;
    color: var(--color-highlight);
    font-size: 0.75rem;
    font-weight: 600;
    cursor: pointer;
    padding: 4px 0;
    margin-top: 5px;
    display: block;
    text-decoration: underline;
    opacity: 0.8;
}

.btn-text:hover {
    opacity: 1;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateY(-5px); }
    to { opacity: 1; transform: translateY(0); }
}

.btn-secondary {
    background-color: var(--color-secondary);
    border: 1px solid var(--color-border);
    color: var(--color-foreground);
}

.btn-secondary:hover {
    background-color: var(--color-muted);
}

.text-destructive {
    color: var(--color-destructive) !important;
}

.impossible-warning {
    color: var(--color-destructive);
    background: rgba(239, 68, 68, 0.1);
    padding: 10px;
    border-radius: 8px;
    border: 1px solid rgba(239, 68, 68, 0.2);
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
    margin-bottom: 8px;
    font-size: 0.813rem;
}

.impossible-warning i {
    width: 18px;
    height: 18px;
}

/* Responsive */
@media (max-width: 1024px) {
    .viz-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .sidebar {
        width: 80px;
        padding: 1rem;
    }
    .sidebar .logo span, .sidebar nav span, .sidebar .dropzone p, .sidebar .dropzone span {
        display: none;
    }
    .main-content {
        margin-left: 80px;
    }
    .kpi-grid {
        grid-template-columns: 1fr;
    }
}