:root {
    /* Color Palette - Calm Light Blue & Off-White SaaS Theme */
    --color-bg: #F8FAFC;
    /* Very subtle off-white/blue cool tint */
    --color-surface: #FFFFFF;
    --color-primary: #3B82F6;
    /* Soft but clear Blue */
    --color-primary-hover: #2563EB;
    --color-text-main: #1E293B;
    /* Slate 800 - High contrast but not harsh black */
    --color-text-secondary: #475569;
    /* Slate 600 */
    --color-border: #E2E8F0;
    --color-accent: #EFF6FF;
    /* Blue 50 */
    --color-focus: #3B82F6;
    /* Focus ring color */

    /* Typography */
    --font-heading: 'Epilogue', sans-serif;
    --font-body: 'Inter', sans-serif;

    /* Spacing */
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 32px;
    --spacing-xl: 64px;

    /* Radius */
    --radius-md: 12px;
    --radius-lg: 20px;
}

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

body {
    font-family: var(--font-body);
    background-color: var(--color-bg);
    color: var(--color-text-main);
    line-height: 1.6;
    font-size: 18px;
    /* Increased base size for readability */
    overflow-x: hidden;
}

/* Accessibility Utilities */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

button:focus-visible,
textarea:focus-visible {
    outline: 3px solid var(--color-focus);
    outline-offset: 2px;
}

/* Layout */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    /* SaaS style header */
}

.logo {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--color-primary);
}

.nav-btn {
    background: none;
    border: none;
    cursor: pointer;
    font-family: var(--font-body);
    color: var(--color-text-secondary);
    font-weight: 500;
    font-size: 1rem;
}

.nav-btn.subtle {
    padding: 8px 16px;
    border-radius: 6px;
    transition: background 0.2s;
}

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

#app-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    min-height: 85vh;
    display: flex;
    /* To stretch screens */
    flex-direction: column;
}

/* Screens */
.screen {
    display: none;
    opacity: 0;
    transition: opacity 0.4s ease;
    flex: 1;
}

.screen.active {
    display: flex;
    flex-direction: column;
    opacity: 1;
}

.content-wrapper {
    width: 100%;
    margin: auto;
}

.content-wrapper.centered {
    text-align: center;
}

/* Hero Section Specifics */
.hero-container {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: var(--spacing-xl) 0;
    width: 100%;
}

.hero-content {
    max-width: 800px;
    text-align: center;
}

/* Typography & Elements */
h1.hero-title {
    font-family: var(--font-heading);
    font-size: 3.5rem;
    /* Larger SaaS headline */
    line-height: 1.1;
    margin-bottom: var(--spacing-md);
    color: var(--color-text-main);
    letter-spacing: -0.02em;
}

h2 {
    font-family: var(--font-heading);
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

p.hero-subtitle {
    font-size: 1.35rem;
    /* Larger subtitle */
    color: var(--color-text-secondary);
    max-width: 680px;
    margin: 0 auto var(--spacing-lg);
    font-weight: 400;
}

.hero-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.hero-reassurance {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-md);
}

.trust-signal {
    display: inline-block;
    background-color: #E0F2FE;
    /* Very light blue approachability badge */
    color: #0369A1;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
}

p.instruction-text {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

.step-indicator {
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 1px;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

/* Buttons */
.btn-primary {
    background-color: var(--color-primary);
    color: white;
    border: none;
    padding: 16px 36px;
    font-size: 1.125rem;
    border-radius: 8px;
    /* Slightly more square for SaaS look */
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    font-weight: 600;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--color-primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.btn-text,
.text-btn {
    background: none;
    border: none;
    color: var(--color-primary);
    padding: 16px 24px;
    font-size: 1.125rem;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
}

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

.btn-secondary {
    background: transparent;
    color: var(--color-text-secondary);
    border: 1px solid var(--color-border);
    padding: 14px 28px;
    font-size: 1rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    font-weight: 500;
}

.btn-secondary:hover {
    border-color: var(--color-text-secondary);
    color: var(--color-text-main);
}

.button-row {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
    justify-content: flex-start;
}

/* Input Screen */
.input-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

textarea {
    width: 100%;
    min-height: 200px;
    padding: var(--spacing-md);
    font-family: var(--font-body);
    font-size: 1.1rem;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    resize: vertical;
    transition: border-color 0.2s;
}

textarea:focus {
    outline: none;
    border-color: var(--color-primary);
}

.quick-actions {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
    flex-wrap: wrap;
}

.chip {
    background: var(--color-accent);
    color: var(--color-primary);
    border: none;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    cursor: pointer;
    transition: background 0.2s;
}

.chip:hover {
    background: #D5EBE0;
}

/* Preferences */
.prefs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--spacing-md);
}

.pref-card {
    background: var(--color-surface);
    border: 2px solid var(--color-border);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    text-align: left;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.pref-card:hover {
    border-color: var(--color-primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.pref-card.selected {
    border-color: var(--color-primary);
    background-color: var(--color-accent);
}

.pref-card .icon {
    font-size: 1.5rem;
}

.pref-card .title {
    font-weight: 600;
    color: var(--color-text-main);
}

.pref-card .desc {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
}

/* Loading */
.loader-animation {
    margin-bottom: var(--spacing-lg);
}

.pulse-circle {
    width: 60px;
    height: 60px;
    background-color: var(--color-primary);
    border-radius: 50%;
    margin: 0 auto;
    animation: pulse 2s infinite ease-in-out;
}

@keyframes pulse {
    0% {
        transform: scale(0.8);
        opacity: 0.6;
    }

    50% {
        transform: scale(1.1);
        opacity: 1;
    }

    100% {
        transform: scale(0.8);
        opacity: 0.6;
    }
}

/* Output */
.output-card {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.04);
    margin-bottom: var(--spacing-md);
    min-height: 300px;
}

.output-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.badge {
    background: var(--color-accent);
    color: var(--color-primary);
    padding: 6px 12px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.result-content {
    font-size: 1.25rem;
    /* Large readable text */
    line-height: 1.8;
}

.result-content h3 {
    font-family: var(--font-heading);
    color: var(--color-primary);
    margin-top: 1.5rem;
    margin-bottom: 0.5rem;
    font-size: 1.5rem;
}

.result-content ul {
    list-style: none;
    /* Custom bullets */
    padding-left: 0;
}

.result-content li {
    margin-bottom: 1rem;
    position: relative;
    padding-left: 1.5rem;
}

.result-content li::before {
    content: "•";
    color: var(--color-primary);
    position: absolute;
    left: 0;
    font-weight: bold;
}

.impact-section {
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-border);
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Comparison View */
.hidden {
    display: none;
}

.compare-container {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    background: white;
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
}

.compare-col.arrow {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--color-text-secondary);
}

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

/* Hide Visual Aid in Comparison View */
.compare-container .visual-aid {
    display: none;
}

/* Animations */
.fade-in {
    opacity: 0;
    transform: translateY(10px);
    animation: fadeInUp 0.6s forwards;
}

.delay-1 {
    animation-delay: 0.2s;
}

.delay-2 {
    animation-delay: 0.4s;
}

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

/* Info / Features Screen */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.feature-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    transition: transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
    border-color: var(--color-primary);
}

.feature-card .feature-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
    display: block;
}

.feature-card h3 {
    font-size: 1.25rem;
    color: var(--color-text-main);
    margin-bottom: var(--spacing-sm);
    font-weight: 700;
}

.feature-card p {
    color: var(--color-text-secondary);
    font-size: 1rem;
    line-height: 1.6;
}

/* Responsive */
@media (max-width: 768px) {
    h1.hero-title {
        font-size: 2.25rem;
    }

    #app-container {
        padding: var(--spacing-md);
    }

    .hero-actions {
        flex-direction: column;
        width: 100%;
    }

    .btn-primary,
    .btn-text {
        width: 100%;
    }

    .compare-container {
        grid-template-columns: 1fr;
    }

    .compare-col.arrow {
        transform: rotate(90deg);
        padding: 10px;
    }
}