/* Modern CSS Variables */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --secondary: #8b5cf6;
    --accent: #06b6d4;
    --success: #10b981;
    --error: #ef4444;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-600: #4b5563;
    --gray-800: #1f2937;
    --gray-900: #111827;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--gray-800);
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--gray-200);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 4rem;
}

.nav-logo h1 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--gray-600);
    font-weight: 500;
    transition: color 0.2s;
}

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

.nav-login {
    background: var(--primary) !important;
    color: white !important;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
}

.nav-login:hover { background: var(--primary-dark) !important; }

.nav-mobile { display: none; }

/* Hero Section */
.hero {
    padding: 8rem 0 4rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    position: relative;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

.gradient-text {
    background: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: 1rem;
}

.hero-description {
    font-size: 1rem;
    opacity: 0.7;
    margin-bottom: 2rem;
    max-width: 600px;
    line-height: 1.6;
}

/* Call Controls */
.call-controls {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

/* Verification Stages */
.verification-stage {
    background: rgba(255, 255, 255, 0.1);
    padding: 2rem;
    border-radius: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    text-align: center;
}

.verification-stage h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: white;
}

.verification-stage p {
    opacity: 0.9;
    margin-bottom: 1.5rem;
}

/* Email Input Stage */
.email-input-group {
    display: flex;
    gap: 1rem;
    align-items: center;
    max-width: 500px;
    margin: 0 auto;
}

.email-input-group input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 0.5rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(5px);
    color: white;
    font-size: 1rem;
}

.email-input-group input::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.email-input-group input:focus {
    outline: none;
    border-color: rgba(255, 255, 255, 0.5);
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.1);
}

/* Verification Code Stage */
.verification-input-group {
    display: flex;
    gap: 1rem;
    align-items: center;
    max-width: 400px;
    margin: 0 auto;
}

.verification-input-group input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 0.5rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(5px);
    color: white;
    font-size: 1.2rem;
    text-align: center;
    letter-spacing: 0.2rem;
}

.verification-input-group input::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.verification-input-group input:focus {
    outline: none;
    border-color: rgba(255, 255, 255, 0.5);
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.1);
}

.verification-help {
    margin-top: 1rem;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 0.5rem;
    font-size: 0.9rem;
    opacity: 0.8;
}

.verification-help p {
    margin: 0;
}

.link-button {
    background: none;
    border: none;
    color: #667eea;
    text-decoration: underline;
    cursor: pointer;
    font-size: inherit;
    padding: 0;
}

.link-button:hover {
    color: #5a6fd8;
}

/* Call Controls Stage */
.call-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
}

/* Status Messages */
.status-message {
    margin-top: 1rem;
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    font-size: 0.9rem;
}

.status-message.success {
    background: rgba(46, 204, 113, 0.2);
    border: 1px solid rgba(46, 204, 113, 0.4);
    color: #2ecc71;
}

.status-message.error {
    background: rgba(231, 76, 60, 0.2);
    border: 1px solid rgba(231, 76, 60, 0.4);
    color: #e74c3c;
}

.status-message.loading {
    background: rgba(99, 102, 241, 0.2);
    border: 1px solid rgba(99, 102, 241, 0.4);
    color: #6366f1;
}

.call-section .cta-button {
    margin: 0 0.5rem;
}

.cta-button {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 1.5rem;
    border: none;
    border-radius: 0.75rem;
    font-size: 1.125rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
}

.cta-button.primary {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.cta-button.primary:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-1px);
}

.cta-button.secondary {
    background: rgba(239, 68, 68, 0.2);
    color: white;
    border: 1px solid rgba(239, 68, 68, 0.3);
}

/* Call Status */
.call-status {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: rgba(255, 255, 255, 0.1);
    padding: 0.75rem 1rem;
    border-radius: 0.75rem;
    margin-bottom: 1rem;
}

.status-indicator {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--success);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* Audio Visualizer */
.audio-visualizer {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.25rem;
    height: 40px;
}

.visualizer-bar {
    width: 4px;
    background: rgba(255, 255, 255, 0.7);
    border-radius: 2px;
    animation: visualizer 1s ease-in-out infinite;
}

.visualizer-bar:nth-child(2) { animation-delay: 0.1s; }
.visualizer-bar:nth-child(3) { animation-delay: 0.2s; }
.visualizer-bar:nth-child(4) { animation-delay: 0.3s; }
.visualizer-bar:nth-child(5) { animation-delay: 0.4s; }

@keyframes visualizer {
    0%, 100% { height: 10px; }
    50% { height: 30px; }
}

/* Demo Phone */
.hero-demo { display: flex; justify-content: center; }

.demo-phone {
    width: 320px;
    height: 640px;
    background: linear-gradient(135deg, #1f2937 0%, #374151 100%);
    border-radius: 2rem;
    padding: 1rem;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: white;
    border-radius: 1.5rem;
    padding: 1.5rem;
    overflow: hidden;
}

.demo-conversation {
    height: 100%;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.message {
    max-width: 80%;
    animation: fadeInUp 0.5s ease-out;
}

.message.user { align-self: flex-end; }
.message.assistant { align-self: flex-start; }

.message-content {
    padding: 0.75rem 1rem;
    border-radius: 0.75rem;
    font-size: 0.875rem;
}

.message.user .message-content {
    background: var(--primary);
    color: white;
}

.message.assistant .message-content {
    background: var(--gray-100);
    color: var(--gray-800);
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Features Section */
.features {
    padding: 5rem 0;
    background: var(--gray-50);
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 4rem;
    color: var(--gray-900);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    transition: all 0.3s;
    border: 1px solid var(--gray-200);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
}

.feature-icon i { color: white; width: 24px; height: 24px; }

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.feature-card p { color: var(--gray-600); }

/* Contact Upload */
.contact-upload {
    padding: 5rem 0;
    background: white;
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--gray-600);
    text-align: center;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.upload-container { max-width: 600px; margin: 0 auto; }

.upload-zone {
    border: 2px dashed var(--gray-300);
    border-radius: 1rem;
    padding: 3rem;
    text-align: center;
    transition: all 0.3s;
    cursor: pointer;
}

.upload-zone:hover,
.upload-zone.dragover {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.05);
}

.upload-icon {
    width: 48px;
    height: 48px;
    color: var(--gray-300);
    margin-bottom: 1rem;
}

.upload-zone h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.upload-zone p {
    color: var(--gray-500);
    margin-bottom: 1.5rem;
}

.upload-button {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 600;
    cursor: pointer;
}

.upload-button:hover { background: var(--primary-dark); }

.upload-progress { margin-top: 1.5rem; }

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--gray-200);
    border-radius: 0.375rem;
    overflow: hidden;
    margin-bottom: 0.75rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, var(--secondary) 100%);
    transition: width 0.3s;
    width: 0%;
}

.upload-result {
    margin-top: 1.5rem;
    text-align: center;
}

.result-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 1rem;
}

.result-icon.success { color: var(--success); }
.result-icon.error { color: var(--error); }

/* About Section */
.about {
    padding: 5rem 0;
    background: var(--gray-900);
    color: white;
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text h2 {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.about-text p {
    font-size: 1.125rem;
    opacity: 0.9;
    margin-bottom: 1.5rem;
}

.tech-stack h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.tech-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tech-badge {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.about-stats {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.stat { text-align: center; }

.stat-number {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1.125rem;
    opacity: 0.8;
}

/* Footer */
.footer {
    background: var(--gray-900);
    color: white;
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 4rem;
    margin-bottom: 3rem;
}

.footer-brand h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.footer-section h4 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.footer-section a {
    display: block;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    margin-bottom: 0.5rem;
    transition: color 0.2s;
}

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

.footer-cta {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--primary);
    color: white !important;
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    transition: background-color 0.2s;
}

.footer-cta:hover { background: var(--primary-dark); }

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 2rem;
    border-top: 1px solid var(--gray-800);
}

.footer-legal {
    display: flex;
    gap: 1.5rem;
}

.footer-legal a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links { display: none; }
    .nav-mobile { display: block; }
    .hero-container { grid-template-columns: 1fr; text-align: center; }
    .hero-title { font-size: 2.25rem; }
    .features-grid { grid-template-columns: 1fr; }
    .about-content { grid-template-columns: 1fr; }
    .footer-content { grid-template-columns: 1fr; }
    .footer-links { grid-template-columns: 1fr; }
    .footer-bottom { flex-direction: column; gap: 1rem; }
}

@media (max-width: 480px) {
    .container { padding: 0 1rem; }
    .hero { padding: 6rem 0 3rem; }
    .demo-phone { width: 280px; height: 560px; }
    .call-controls { flex-direction: column; align-items: center; }
    .email-input-group, .verification-input-group { flex-direction: column; }
    .verification-stage { padding: 1.5rem; }
    .call-buttons { flex-direction: column; }
}