:root {
    --bg-deep: #0b0e14;
    --bg-card: #151921;
    --bg-input: #1c212b;
    --border-color: #2d333d;
    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --accent-purple: #8957e5;
    --accent-purple-hover: #a371f7;
    --accent-green: #238636;
    --accent-green-hover: #2ea043;
    --danger: #da3633;
    --font-main: 'Inter', system-ui, -apple-system, sans-serif;
    --font-display: 'Outfit', sans-serif;
    --radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --glow-purple: 0 0 20px rgba(137, 87, 229, 0.4);
    --bg-overlay: rgba(11, 14, 20, 0.8);
}

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&family=Outfit:wght@600;700&display=swap');

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

body {
    background-color: var(--bg-deep);
    color: var(--text-primary);
    font-family: var(--font-main);
    line-height: 1.5;
    overflow-x: hidden;
}

/* Layout Containers */
.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    padding: 2rem;
    gap: 2rem;
    max-width: 1400px;
    margin: 0 auto;
}

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

.header h1 {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.03em;
}

.header span {
    color: var(--accent-purple);
}

.text-secondary { color: var(--text-secondary); }
.mb-1 { margin-bottom: 1rem; }
.mb-half { margin-bottom: 0.5rem; }
.flex { display: flex; }
.gap-1 { gap: 1rem; }
.gap-half { gap: 0.5rem; }
.flex-1 { flex: 1; }
.align-center { align-items: center; }
.font-sm { font-size: 0.85rem; }

/* Hero Section Styles */
.hero-section {
    padding: 2rem 0 4rem;
    text-align: center;
}

.hero-title {
    font-family: var(--font-display);
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #fff, var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto 3rem;
}

.hero-visualizer {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: 0 20px 40px rgba(0,0,0,0.3);
}

/* Main Two-Column Layout */
.main-grid {
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: 2rem;
    align-items: start;
}

/* Sidebar / Left Panel */
.panel {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1.5rem;
}

.panel-title {
    font-family: var(--font-display);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.title-lg {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
}

.form-group {
    margin-bottom: 1.25rem;
}

label {
    display: block;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

select, input {
    width: 100%;
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 0.75rem;
    border-radius: var(--radius);
    font-size: 0.9rem;
    outline: none;
    transition: var(--transition);
}

select:focus {
    border-color: var(--accent-purple);
}

.btn {
    cursor: pointer;
    border: none;
    border-radius: var(--radius);
    font-weight: 600;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    padding: 0.75rem 1.25rem;
}

.btn-primary {
    background: var(--accent-purple);
    color: white;
    width: 100%;
}

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

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    padding: 0.4rem 0.8rem;
    font-size: 0.8rem;
}

.btn-ghost:hover {
    color: var(--text-primary);
    background: rgba(255,255,255,0.05);
}

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

.btn-outline:hover {
    border-color: var(--text-secondary);
    background: rgba(255,255,255,0.05);
}

.btn-success {
    background: var(--accent-green);
    color: white;
    padding: 1.25rem 3rem;
    font-size: 1.1rem;
    border-radius: 50px;
    box-shadow: 0 4px 20px rgba(35, 134, 54, 0.3);
}

.btn-success:hover {
    background: var(--accent-green-hover);
}

/* Right Panel / Course List */
.course-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.course-card {
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.course-info h4 {
    font-size: 0.95rem;
    margin-bottom: 0.25rem;
}

.course-info p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.faculty-tag {
    color: var(--accent-purple);
    font-weight: 500;
}

.slot-badge {
    background: rgba(137, 87, 229, 0.1);
    color: var(--accent-purple);
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    margin-left: 8px;
}

.remove-btn {
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.5rem;
}

.remove-btn:hover {
    color: var(--danger);
}

/* Timetable Section */
.timetable-container {
    margin-top: 1rem;
}

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

.timetable-header-text h2 {
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
}

.timetable-header-text p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.grid-wrapper {
    overflow-x: auto;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    background: var(--bg-card);
}

.timetable-grid {
    display: grid;
    grid-template-columns: 80px repeat(10, 1fr);
    min-width: 900px;
}

.grid-cell {
    border: 0.5px solid var(--border-color);
    min-height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    color: var(--text-secondary);
    transition: var(--transition);
}

.grid-header {
    background: var(--bg-input);
    font-weight: 600;
    color: var(--text-primary);
    text-transform: uppercase;
    font-size: 0.7rem;
    letter-spacing: 0.05em;
}

.grid-cell.active {
    background: var(--accent-purple);
    color: white;
    border: none;
    z-index: 2;
    font-weight: 700;
    box-shadow: var(--glow-purple);
    position: relative;
}

.grid-cell.disabled {
    opacity: 0.3;
    background: #1c212b;
    cursor: not-allowed !important;
}

.grid-cell.clickable:hover {
    background: rgba(137, 87, 229, 0.15);
    border-color: var(--accent-purple);
    color: var(--text-primary);
    cursor: pointer;
    z-index: 1;
}

/* Carousel / Results */
.carousel-container {
    display: flex;
    overflow-x: auto;
    gap: 1.5rem;
    padding: 1rem 0 2rem;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.carousel-container::-webkit-scrollbar {
    display: none;
}

.mini-timetable {
    flex: 0 0 350px;
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1rem;
    transition: var(--transition);
}

.mini-timetable:hover {
    transform: translateY(-4px);
    border-color: var(--accent-purple);
}

.mini-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 2px;
    background: var(--border-color);
    border: 1px solid var(--border-color);
    margin-top: 1rem;
}

.mini-cell {
    aspect-ratio: 1;
    background: var(--bg-card);
}

.mini-cell.filled {
    background: var(--accent-purple);
}

/* Bottom Action */
.actions-footer {
    display: flex;
    justify-content: center;
    padding: 2rem 0;
}

/* Results Section */
.results-section {
    border-top: 1px solid var(--border-color);
    padding-top: 3rem;
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.result-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1.5rem;
    position: relative;
    transition: var(--transition);
}

.result-card:hover {
    border-color: var(--accent-purple);
}

.recommendation-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--accent-green);
    color: white;
    font-size: 0.7rem;
    padding: 2px 8px;
    border-radius: 10px;
    font-weight: 600;
}

.result-meta {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.placeholder-icon {
    width: 16px;
    height: 16px;
    background: currentColor;
    opacity: 0.2;
    mask-size: contain;
    mask-repeat: no-repeat;
}