:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --secondary: #8b5cf6;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --info: #3b82f6;
    --light: #f3f4f6;
    --dark: #1f2937;
    --text: #374151;
    --text-light: #6b7280;
    --border: #e5e7eb;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text);
    background-color: var(--light);
    line-height: 1.6;
}

/* Mobile-first layout */
.container-custom {
    max-width: 100%;
    padding: 1rem;
}

@media (min-width: 768px) {
    .container-custom {
        max-width: 720px;
        margin: 0 auto;
    }
}

@media (min-width: 1024px) {
    .container-custom {
        max-width: 960px;
    }
}

/* Custom buttons */
.btn-custom {
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 600;
    transition: all 0.2s;
    border: none;
    cursor: pointer;
}

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

.btn-primary-custom:hover {
    background-color: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

/* Cards */
.card-custom {
    background: white;
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    margin-bottom: 1rem;
}

.card-custom:hover {
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.15);
    transition: box-shadow 0.2s;
}

/* Progress bars */
.progress-custom {
    height: 0.5rem;
    background-color: var(--border);
    border-radius: 1rem;
    overflow: hidden;
}

.progress-bar-custom {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    border-radius: 1rem;
    transition: width 0.3s;
}

/* Logo and branding */
.logo-container {
    display: inline-block;
}

.logo-icon {
    filter: drop-shadow(0 4px 6px rgba(0, 0, 0, 0.1));
}

.slogan {
    font-size: 1.25rem;
    font-weight: 500;
    color: var(--primary);
    font-style: italic;
}

.feature-icon {
    color: var(--primary);
    margin: 0 auto;
}

/* Form inputs */
.input-custom {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border);
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: border-color 0.2s;
}

.input-custom:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

/* Video player */
.video-container {
    position: relative;
    width: 100%;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    background-color: #000;
    border-radius: 1rem;
    overflow: hidden;
}

.video-container video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
}

/* Schedule timeline */
.timeline-item {
    position: relative;
    padding-left: 2rem;
    padding-bottom: 1.5rem;
    border-left: 2px solid var(--border);
}

.timeline-item:last-child {
    border-left: 2px solid transparent;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -6px;
    top: 0.5rem;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--primary);
}

.timeline-item.completed::before {
    background-color: var(--success);
}

/* Badge styles */
.badge-custom {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 1rem;
    font-size: 0.875rem;
    font-weight: 600;
}

.badge-visual {
    background-color: #dbeafe;
    color: #1e40af;
}

.badge-auditory {
    background-color: #fce7f3;
    color: #9f1239;
}

.badge-kinesthetic {
    background-color: #d1fae5;
    color: #065f46;
}

.badge-mixed {
    background-color: #e9d5ff;
    color: #6b21a8;
}

/* Loading spinner */
.spinner {
    border: 3px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Stats grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.stat-card {
    background: white;
    padding: 1.5rem;
    border-radius: 0.75rem;
    text-align: center;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-top: 0.25rem;
}

/* Topic cards */
.topic-card {
    background: white;
    border-radius: 0.75rem;
    padding: 1rem;
    margin-bottom: 0.75rem;
    border-left: 4px solid var(--primary);
    cursor: pointer;
    transition: all 0.2s;
}

.topic-card:hover {
    transform: translateX(4px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.topic-card.beginner {
    border-left-color: var(--success);
}

.topic-card.intermediate {
    border-left-color: var(--warning);
}

.topic-card.advanced {
    border-left-color: var(--danger);
}

/* Quiz options */
.quiz-option {
    background: white;
    border: 2px solid var(--border);
    border-radius: 0.75rem;
    padding: 1rem;
    margin-bottom: 0.75rem;
    cursor: pointer;
    transition: all 0.2s;
}

.quiz-option:hover {
    border-color: var(--primary);
    background-color: #f0f9ff;
}

.quiz-option.selected {
    border-color: var(--primary);
    background-color: #eff6ff;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

/* Navigation */
.navbar-custom {
    background: white;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    padding: 1rem 0;
    margin-bottom: 1.5rem;
}

/* Alerts */
.alert-custom {
    padding: 1rem 1.25rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
}

.alert-success {
    background-color: #d1fae5;
    color: #065f46;
    border-left: 4px solid var(--success);
}

.alert-error {
    background-color: #fee2e2;
    color: #991b1b;
    border-left: 4px solid var(--danger);
}

.alert-info {
    background-color: #dbeafe;
    color: #1e40af;
    border-left: 4px solid var(--info);
}

/* File upload area */
.upload-area {
    border: 2px dashed var(--border);
    border-radius: 1rem;
    padding: 3rem 2rem;
    text-align: center;
    background-color: #fafafa;
    cursor: pointer;
    transition: all 0.2s;
}

.upload-area:hover {
    border-color: var(--primary);
    background-color: #f0f9ff;
}

.upload-area.dragover {
    border-color: var(--primary);
    background-color: #eff6ff;
    transform: scale(1.02);
}

/* Utility classes */
.text-primary { color: var(--primary); }
.text-secondary { color: var(--secondary); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-muted { color: var(--text-light); }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

.text-center { text-align: center; }
.text-right { text-align: right; }

.hidden { display: none; }

/* Responsive utilities */
@media (max-width: 767px) {
    .hide-mobile { display: none; }
}

@media (min-width: 768px) {
    .hide-desktop { display: none; }
}