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

:root {
    /* Colors */
    --primary-color: #667eea;
    --primary-dark: #5a67d8;
    --secondary-color: #764ba2;
    --accent-color: #f093fb;
    --text-primary: #2d3748;
    --text-secondary: #718096;
    --text-light: #a0aec0;
    --bg-primary: #ffffff;
    --bg-secondary: #f7fafc;
    --bg-card: #ffffff;
    --border-color: #e2e8f0;
    --shadow-light: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-medium: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-large: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    
    /* Typography */
    --font-family: 'Inter', system-ui, -apple-system, sans-serif;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 300ms ease-in-out;
    --transition-slow: 500ms ease-in-out;
    
    /* Animations */
    --animation-bounce: bounce 0.6s ease-in-out;
    --animation-fade-in: fadeIn 0.3s ease-out;
    --animation-slide-up: slideUp 0.4s ease-out;
    --animation-scale: scale 0.2s ease-out;
}

/* Keyframe Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes bounce {
    0%, 20%, 53%, 80%, 100% {
        animation-timing-function: cubic-bezier(0.215, 0.610, 0.355, 1.000);
        transform: translate3d(0,0,0);
    }
    40%, 43% {
        animation-timing-function: cubic-bezier(0.755, 0.050, 0.855, 0.060);
        transform: translate3d(0, -10px, 0);
    }
    70% {
        animation-timing-function: cubic-bezier(0.755, 0.050, 0.855, 0.060);
        transform: translate3d(0, -5px, 0);
    }
    90% {
        transform: translate3d(0,-2px,0);
    }
}

@keyframes scale {
    from {
        transform: scale(0.9);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

@keyframes pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
    100% {
        transform: scale(1);
    }
}

body {
    font-family: var(--font-family);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    overflow-x: hidden;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: var(--transition-normal);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.nav-logo h2 {
    font-size: 1.5rem;
    font-weight: var(--font-weight-bold);
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: var(--font-weight-medium);
    transition: var(--transition-fast);
    position: relative;
}

.nav-link:hover {
    color: var(--primary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition-fast);
}

.nav-link:hover::after {
    width: 100%;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: var(--font-weight-medium);
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-normal);
    position: relative;
    overflow: visible;
    user-select: none;
    -webkit-user-select: none;
    transform-origin: center;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: radial-gradient(circle, rgba(255,255,255,0.3) 0%, transparent 70%);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.3s ease, height 0.3s ease;
    z-index: 1;
}

.btn:active::before {
    width: 300px;
    height: 300px;
}

.btn:active {
    transform: scale(0.98);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    box-shadow: var(--shadow-medium);
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1rem;
    position: relative;
    background-size: 200% 200%;
    animation: var(--animation-fade-in);
}

.btn-primary::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, var(--primary-dark) 0%, #5f4b8b 100%);
    opacity: 0;
    transition: opacity var(--transition-normal);
    border-radius: inherit;
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    background-position: 100% 100%;
}

.btn-primary:hover::after {
    opacity: 1;
}

.btn-primary * {
    position: relative;
    z-index: 2;
}

.btn-secondary {
    background: transparent;
    color: var(--text-secondary);
    border: 2px solid var(--border-color);
    padding: calc(var(--spacing-md) - 2px) var(--spacing-xl);
    font-size: 1rem;
    animation: var(--animation-fade-in);
    animation-delay: 0.1s;
    animation-fill-mode: both;
}

.btn-secondary:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
    background: rgba(102, 126, 234, 0.05);
}

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
    position: relative;
    overflow: hidden;
}

.btn-outline::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: var(--primary-color);
    transition: left var(--transition-normal);
    z-index: 1;
}

.btn-outline:hover::before {
    left: 0;
}

.btn-outline:hover {
    color: white;
}

.btn-outline span {
    position: relative;
    z-index: 2;
}

.btn-icon {
    transition: var(--transition-normal);
    display: inline-flex;
    align-items: center;
}

.btn-primary:hover .btn-icon {
    transform: translateX(3px) scale(1.1);
}

.btn-secondary:hover .btn-icon {
    transform: translateX(2px);
}

/* Button focus states */
.btn:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.3);
}

/* Loading state */
.btn.loading {
    pointer-events: none;
    opacity: 0.7;
}

.btn.loading::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    border: 2px solid transparent;
    border-top: 2px solid currentColor;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Hero Section */
.hero {
    padding: calc(70px + var(--spacing-3xl)) var(--spacing-lg) calc(var(--spacing-3xl) + 4rem);
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 40%;
    height: 200%;
    background: linear-gradient(45deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(3deg); }
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    max-width: 600px;
    animation: var(--animation-slide-up);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: var(--font-weight-bold);
    line-height: 1.1;
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
    animation: var(--animation-slide-up);
    animation-delay: 0.2s;
    animation-fill-mode: both;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    background-size: 200% 200%;
    animation: gradient-shift 4s ease-in-out infinite;
}

@keyframes gradient-shift {
    0%, 100% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
}

.hero-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
    animation: var(--animation-slide-up);
    animation-delay: 0.4s;
    animation-fill-mode: both;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
    animation: var(--animation-slide-up);
    animation-delay: 0.6s;
    animation-fill-mode: both;
}

/* Hero Visual */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: var(--animation-scale);
    animation-delay: 0.8s;
    animation-fill-mode: both;
    position: relative;
    padding: 3rem;
}

.hero-visual::before {
    content: '';
    position: absolute;
    inset: -40px -90px -40px -60px;
    background: linear-gradient(120deg, rgba(237, 242, 255, 0.9) 0%, rgba(199, 210, 255, 0.88) 45%, rgba(165, 180, 252, 0.86) 100%);
    border-radius: 200px;
    z-index: -3;
    opacity: 0.72;
}

.note-preview {
    position: relative;
    display: inline-block;
    padding: 3rem 3.25rem;
    border-radius: 28px;
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.28) 0%, rgba(255, 255, 255, 0.18) 100%);
    box-shadow: 0 24px 48px rgba(79, 70, 229, 0.22);
    max-width: 360px;
    width: 100%;
    border: 1px solid rgba(255, 255, 255, 0.35);
    backdrop-filter: blur(22px);
    transform: translateY(0);
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
    z-index: 1;
}

.note-preview::before {
    content: '';
    position: absolute;
    inset: -18px;
    background: radial-gradient(circle at top left, rgba(255, 255, 255, 0.58) 0%, rgba(165, 180, 252, 0.32) 55%, rgba(129, 140, 248, 0.24) 100%);
    border-radius: 32px;
    z-index: -2;
    filter: blur(20px);
}

.note-preview::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 28px;
    background: linear-gradient(160deg, rgba(255, 255, 255, 0.68) 0%, rgba(255, 255, 255, 0) 55%, rgba(255, 255, 255, 0.18) 100%);
    mix-blend-mode: screen;
    opacity: 0.92;
    z-index: -1;
}

.note-preview:hover {
    transform: translateY(-8px);
    box-shadow: 0 30px 60px rgba(79, 70, 229, 0.28);
}


.note-header {
    margin-bottom: 0.5 rem;
    background: rgba(255, 255, 255, 0.85);
    padding: 1rem 1.5rem;
    border-radius: 18px;
    box-shadow: 0 12px 30px rgba(79, 70, 229, 0.12);
    border: 1px solid rgba(255, 255, 255, 0.55);
}

.note-text h4 {
    font-size: 1.1rem;
    letter-spacing: 0.01em;
}

.note-text p {
    font-size: 0.95rem;
}


.note-item {
    display: flex;
    align-items: flex-start;
    gap: 1.25rem;
    padding: 1.2rem 0;
    border-bottom: 1px solid rgba(226, 232, 240, 0.32);
}

.note-item:last-child {
    border-bottom: none;
}

.note-header {
    background: var(--bg-secondary);
    padding: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.note-controls {
    display: flex;
    gap: var(--spacing-xs);
}

.control-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.control-dot.red { background: #ef4444; }
.control-dot.yellow { background: #f59e0b; }
.control-dot.green { background: #10b981; }

.note-title {
    font-weight: var(--font-weight-semibold);
    color: var(--text-secondary);
}

.note-content {
    padding: var(--spacing-lg);
}

.note-item {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--border-color);
}

.note-item:last-child {
    border-bottom: none;
}

.note-icon {
    font-size: 1.5rem;
    min-width: 2rem;
}

.note-text h4 {
    font-size: 0.875rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
}

.note-text p {
    font-size: 0.75rem;
    color: var(--text-light);
    line-height: 1.4;
}

/* Features Section */
.features {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-primary);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-3xl);
    color: var(--text-primary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.feature-card {
    background: var(--bg-card);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-light);
    text-align: center;
    transition: var(--transition-normal);
    border: 1px solid var(--border-color);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-large);
    border-color: var(--primary-color);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-lg);
    display: block;
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

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

/* About Section */
.about {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-secondary);
}

.about-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.about-text {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.stat {
    background: var(--bg-card);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-light);
}

.stat h3 {
    font-size: 1.5rem;
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
}

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

/* Footer */
.footer {
    background: var(--text-primary);
    color: white;
    padding: var(--spacing-xl) 0;
}

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

.footer-brand h3 {
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-sm);
}

.footer-brand p {
    color: var(--text-light);
    font-size: 0.875rem;
}

.footer-links {
    display: flex;
    gap: var(--spacing-lg);
}

.footer-links a {
    color: var(--text-light);
    text-decoration: none;
    font-size: 0.875rem;
    transition: var(--transition-fast);
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

.footer-bottom p {
    color: var(--text-light);
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        gap: var(--spacing-md);
    }
    
    .nav-link {
        display: none;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--spacing-xl);
    }
    
    .hero-cta {
        justify-content: center;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .about-stats {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
        gap: var(--spacing-lg);
        text-align: center;
    }
    
    .note-preview {
        transform: none;
    }
}

@media (max-width: 480px) {
    :root {
        --spacing-lg: 1rem;
        --spacing-xl: 1.5rem;
        --spacing-2xl: 2rem;
        --spacing-3xl: 2.5rem;
    }
    
    .hero {
        padding: calc(70px + var(--spacing-xl)) var(--spacing-md) var(--spacing-xl);
    }
    
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }
    
    .btn-primary,
    .btn-secondary {
        width: 100%;
        justify-content: center;
        max-width: 280px;
    }
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Focus styles for accessibility */
.btn:focus,
.nav-link:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Authentication Styles */
.auth-section {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.user-info {
    display: none;
}

.user-profile {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.profile-pic {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    object-fit: cover;
}

.user-details {
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.user-name {
    font-weight: var(--font-weight-medium);
    color: var(--text-primary);
    font-size: 0.875rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.user-email {
    font-size: 0.75rem;
    color: var(--text-secondary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Loading Spinner */
.loading-spinner {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.9);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Toast Notifications */
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    color: white;
    font-weight: var(--font-weight-medium);
    transform: translateX(400px);
    transition: transform var(--transition-normal);
    z-index: 10000;
    box-shadow: var(--shadow-large);
}

.toast.show {
    transform: translateX(0);
}

.toast-success {
    background: linear-gradient(135deg, #10b981, #059669);
}

.toast-error {
    background: linear-gradient(135deg, #ef4444, #dc2626);
}

.toast-info {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
}

/* Authentication state specific styles */
.auth-section.authenticated .user-info {
    display: block;
}

/* Mobile responsive adjustments for auth */
@media (max-width: 768px) {
    .auth-section {
        gap: var(--spacing-sm);
    }
    
    .user-profile {
        padding: var(--spacing-xs) var(--spacing-sm);
    }
    
    .user-name,
    .user-email {
        font-size: 0.75rem;
    }
    
    .profile-pic {
        width: 24px;
        height: 24px;
    }
    
    .toast {
        top: 10px;
        right: 10px;
        left: 10px;
        transform: translateY(-100px);
    }
    
    .toast.show {
        transform: translateY(0);
    }
}