:root {
    --primary: #2563eb;
    --primary-light: #60a5fa;
    --primary-dark: #1d4ed8;
    --surface: #ffffff;
    --surface-2: #f8fafc;
    --surface-3: #f1f5f9;
    --text: #0f172a;
    --text-secondary: #64748b;
    --border: #e2e8f0;
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --container: 1200px;
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Plus Jakarta Sans', sans-serif;
    background-color: var(--surface-2);
    color: var(--text);
    line-height: 1.5;
}

.container {
    width: min(var(--container), 95%);
    margin: 0 auto;
}

/* Header Styles */
.site-header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
    background: rgba(255, 255, 255, 0.8);
}

.header-container {
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.home-link {
    color: var(--text);
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: 700;
}

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

.logo-subtitle {
    color: var(--text-secondary);
    font-weight: 500;
}

/* Hero Section */
.hero-section {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
}

.hero-description {
    font-size: 1.125rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* Main Content Layout */
.main-content {
    padding: 3rem 0;
}

.content-grid {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 2rem;
    align-items: start;
}

/* Sidebar */
.sidebar {
    display: grid;
    gap: 1.5rem;
}

.info-card {
    background: var(--surface);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
}

.card-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text);
}

.steps-list {
    padding-left: 1.5rem;
    color: var(--text-secondary);
}

.steps-list li {
    margin-bottom: 0.75rem;
}

.topic-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    background: var(--surface-3);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Form Styles */
.analysis-card {
    background: var(--surface);
    padding: 2rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text);
}

input[type="text"] {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 2px solid var(--border);
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: all 0.2s;
}

input[type="text"]:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
    outline: none;
}

.primary-button {
    background: var(--primary);
    color: white;
    padding: 0.875rem 1.5rem;
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    width: 100%;
}

.primary-button:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

/* Loading State */
.loading-container {
    text-align: center;
    padding: 3rem;
    background: var(--surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
}

.spinner {
    width: 3rem;
    height: 3rem;
    border: 3px solid var(--surface-3);
    border-top: 3px solid var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin: 0 auto 1rem;
}

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

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

/* Results Section */
.results-section {
    display: grid;
    gap: 1.5rem;
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.timestamp {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.summary-card,
.chart-card,
.word-cloud-card {
    background: var(--surface);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
}

.word-cloud-content {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    padding: 1rem;
    justify-content: center;
}

/* Footer */
.site-footer {
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 1.5rem 0;
    margin-top: 4rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-secondary);
}

/* Responsive Design */
@media (max-width: 1024px) {
    .content-grid {
        grid-template-columns: 1fr;
    }
    
    .sidebar {
        order: 2;
    }
}

@media (max-width: 768px) {
    .hero-section {
        padding: 3rem 0;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .header-container {
        padding: 0 1rem;
    }
    
    .logo-subtitle {
        display: none;
    }
    
    .analysis-card,
    .loading-container,
    .summary-card,
    .chart-card,
    .word-cloud-card {
        padding: 1.25rem;
    }
}