:root {
    --bg-main: #0D0A19;
    --bg-surface: #171328;
    --bg-surface-hover: #221D3A;

    --primary: #6C5CE7;
    --primary-hover: #5A4BDE;
    --secondary: #A29BFE;
    --accent: #FDCB6E;

    --text-primary: #FFFFFF;
    --text-secondary: #B2BEC3;
    --text-muted: #636E72;

    --border: #2D2745;
    --border-light: #3D355A;

    --error: #FF7675;
    --success: #00B894;

    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;

    --font-sans: 'Inter', sans-serif;
    --font-heading: 'Space Grotesk', sans-serif;
}

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

body {
    font-family: var(--font-sans);
    background-color: var(--bg-main);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

/* Typography */
h1,
h2,
h3,
h4 {
    font-family: var(--font-heading);
    font-weight: 700;
}

.text-primary {
    color: var(--primary);
}

.text-secondary {
    color: var(--text-secondary);
}

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

.text-sm {
    font-size: 0.85rem;
}

.mb-4 {
    margin-bottom: 1rem;
}

.mt-2 {
    margin-top: 0.5rem;
}

.mt-4 {
    margin-top: 1rem;
}

/* Layout */
.app-container {
    display: flex;
    min-height: 100vh;
    max-width: 1400px;
    margin: 0 auto;
}

.sidebar {
    width: 280px;
    background-color: var(--bg-surface);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    padding: 24px;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
}

.workspace {
    flex: 1;
    padding: 40px;
    overflow-y: auto;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 40px;
}

.logo h1 {
    font-size: 1.5rem;
    letter-spacing: -0.5px;
}

.logo span {
    color: var(--primary);
}

/* Settings */
.settings-group {
    margin-bottom: 32px;
}

.settings-group label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
    font-weight: 500;
}

/* Inputs */
.input-select,
.input-text {
    width: 100%;
    background-color: var(--bg-main);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    font-family: var(--font-sans);
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s;
}

.input-select:focus,
.input-text:focus {
    border-color: var(--primary);
}

.input-seamless {
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    outline: none;
    width: 100%;
}

.input-seamless:focus {
    color: var(--primary);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border: none;
    cursor: pointer;
    font-family: var(--font-sans);
    font-weight: 500;
    transition: all 0.2s ease;
    border-radius: var(--radius-sm);
    padding: 10px 16px;
    font-size: 0.95rem;
}

.btn-primary {
    background-color: var(--primary);
    color: #fff;
}

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

.btn-outline {
    background: transparent;
    border: 1px solid var(--border-light);
    color: var(--text-primary);
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.btn-text {
    background: transparent;
    color: var(--text-primary);
    padding: 8px;
}

.btn-text:hover {
    color: var(--primary);
}

.btn-icon {
    background: transparent;
    color: var(--text-muted);
    padding: 6px;
    border-radius: var(--radius-sm);
}

.btn-icon:hover {
    color: var(--error);
    background-color: rgba(255, 118, 117, 0.1);
}

.full-width {
    width: 100%;
}

/* Summary Card */
.summary-card {
    background: linear-gradient(135deg, rgba(108, 92, 231, 0.1) 0%, rgba(108, 92, 231, 0.02) 100%);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: 20px;
    margin-bottom: 32px;
}

.summary-card h3 {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 8px;
}

.cgpa-display {
    font-size: 2.5rem;
    font-family: var(--font-heading);
    font-weight: 700;
    color: var(--primary);
    line-height: 1;
    margin-bottom: 8px;
}

.cgpa-max {
    font-size: 1rem;
    color: var(--text-muted);
    font-family: var(--font-sans);
    font-weight: 400;
}

.credits-display {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.credits-display span {
    color: var(--text-primary);
    font-weight: 600;
}

/* Nav Menu */
.nav-menu {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: auto;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: var(--radius-md);
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-family: var(--font-sans);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    text-align: left;
}

.nav-btn:hover {
    background-color: var(--bg-surface-hover);
    color: var(--text-primary);
}

.nav-btn.active {
    background-color: rgba(108, 92, 231, 0.15);
    color: var(--primary);
    font-weight: 600;
}

.sidebar-footer {
    margin-top: 32px;
}

/* Workspace */
.workspace-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
}

.workspace-header h2 {
    font-size: 1.8rem;
}

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

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

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Semesters & Courses */
.semesters-container {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.card {
    background-color: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
}

.semester-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-light);
}

.semester-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

.semester-gpa {
    font-size: 0.95rem;
    color: var(--text-secondary);
    background: var(--bg-main);
    padding: 6px 12px;
    border-radius: 100px;
    border: 1px solid var(--border-light);
}

.semester-gpa strong {
    color: var(--text-primary);
}

.courses-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 16px;
}

.course-row {
    display: grid;
    grid-template-columns: 1fr 100px 120px 40px;
    gap: 12px;
    align-items: center;
}

/* Target & Insights Tabs */
.target-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.target-input-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.target-result {
    margin-top: 24px;
    padding: 24px;
    background-color: var(--bg-main);
    border-radius: var(--radius-sm);
    border-left: 4px solid var(--primary);
}

.target-result-value {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary);
    margin: 8px 0;
}

.insights-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.chart-card {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.chart-container {
    position: relative;
    width: 200px;
    height: 200px;
    margin: 20px 0;
}

.chart-legend {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    justify-content: center;
    margin-top: 16px;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.legend-color {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.conversion-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.conversion-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background-color: var(--bg-main);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-light);
}

.conv-label {
    font-weight: 500;
}

.conv-value {
    font-family: var(--font-heading);
    color: var(--primary);
    font-weight: 700;
}

/* Responsive */
@media (max-width: 900px) {
    .app-container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        height: auto;
        position: static;
        border-right: none;
        border-bottom: 1px solid var(--border);
    }

    .nav-menu {
        flex-direction: row;
        flex-wrap: wrap;
        margin-top: 24px;
    }

    .course-row {
        grid-template-columns: 1fr;
    }

    .insights-grid,
    .target-grid {
        grid-template-columns: 1fr;
    }
}