/* ========================================
   Breath App - Presentation Website
   Theme: Dark mode with calming ocean colors
   ======================================== */

/* CSS Variables - Theme Colors */
:root {
    /* Base colors from the app */
    --bg-primary: #1e222c;
    --bg-surface: #2a2f3a;
    --bg-elevated: #353a47;

    /* Accent colors */
    --accent-primary: #9fc6a7;
    --accent-teal: #4a8b9c;
    --accent-coral: #d0a3a3;
    --accent-gold: #f2dca2;
    --accent-lilac: #d4c0eb;

    /* Phase colors */
    --color-inhale: #a3cde3;
    --color-hold: #f2dca2;
    --color-exhale: #d3a097;

    /* Dive mode colors */
    --dive-petrol: #375e70;
    --dive-deep: #1a3a4a;
    --dive-teal: #4a8b9c;
    --dive-seafoam: #7bb5a3;
    --dive-coral: #d0a3a3;
    --dive-midnight: #0d2538;

    /* Text colors */
    --text-primary: #f2f2f2;
    --text-secondary: #b8b8b8;
    --text-muted: #7a7a7a;

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #9fc6a7 0%, #4a8b9c 100%);
    --gradient-dive: linear-gradient(180deg, #0d2538 0%, #1a3a4a 50%, #375e70 100%);
    --gradient-hero: linear-gradient(180deg, #1e222c 0%, #2a2f3a 100%);

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 5rem;

    /* Border radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 40px rgba(159, 198, 167, 0.3);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Nunito', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-fast);
}

img {
    max-width: 100%;
    height: auto;
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-normal);
    border: none;
    text-decoration: none;
}

.btn-primary {
    background: var(--accent-primary);
    color: var(--bg-primary);
}

.btn-primary:hover {
    background: #b5d4bb;
    box-shadow: var(--shadow-glow);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--bg-surface);
}

.btn-secondary:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.btn-large {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1.1rem;
}

/* Section styling */
section {
    padding: var(--spacing-2xl) 0;
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--spacing-xl);
}

.section-tag {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-md);
    background: rgba(159, 198, 167, 0.1);
    color: var(--accent-primary);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: var(--spacing-md);
}

.section-header h2 {
    font-size: clamp(2rem, 5vw, 3rem);
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
}

.section-header p {
    color: var(--text-secondary);
    font-size: 1.125rem;
}

/* ========================================
   Navigation
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: var(--spacing-md) 0;
    transition: all var(--transition-normal);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(30, 34, 44, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.logo-icon {
    width: 40px;
    height: 40px;
    color: var(--accent-primary);
}

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

.nav-links a:not(.btn) {
    color: var(--text-secondary);
    font-weight: 500;
    position: relative;
}

.nav-links a:not(.btn):hover {
    color: var(--text-primary);
}

.nav-links a:not(.btn)::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-primary);
    transition: width var(--transition-normal);
}

.nav-links a:not(.btn):hover::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-btn span {
    width: 25px;
    height: 2px;
    background: var(--text-primary);
    transition: all var(--transition-fast);
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: var(--spacing-2xl) var(--spacing-md);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
}

.breathing-orb {
    width: 400px;
    height: 400px;
    border-radius: 50%;
    background: radial-gradient(circle at 30% 30%,
        rgba(159, 198, 167, 0.4) 0%,
        rgba(159, 198, 167, 0.1) 50%,
        transparent 70%);
    filter: blur(60px);
    animation: breathe 8s ease-in-out infinite;
}

@keyframes breathe {
    0%, 100% { transform: scale(0.8); opacity: 0.5; }
    50% { transform: scale(1.2); opacity: 0.8; }
}

.hero-content {
    position: relative;
    text-align: center;
    max-width: 800px;
    z-index: 1;
}

.hero h1 {
    font-size: clamp(2.5rem, 8vw, 4.5rem);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: var(--spacing-md);
}

.gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1rem, 2.5vw, 1.25rem);
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto var(--spacing-xl);
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-xl);
}

.hero-stats {
    display: flex;
    gap: var(--spacing-xl);
    justify-content: center;
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--accent-primary);
}

.stat-label {
    color: var(--text-muted);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.scroll-indicator {
    position: absolute;
    bottom: var(--spacing-lg);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-muted);
    font-size: 0.875rem;
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(10px); }
}

/* ========================================
   Features Section
   ======================================== */
.features {
    background: var(--bg-surface);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.feature-card {
    background: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    transition: all var(--transition-normal);
    border: 1px solid transparent;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: rgba(159, 198, 167, 0.2);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    background: rgba(159, 198, 167, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-md);
    color: var(--accent-color, var(--accent-primary));
}

.feature-icon svg {
    width: 28px;
    height: 28px;
}

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

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ========================================
   Techniques Section
   ======================================== */
.techniques {
    background: var(--bg-primary);
}

.technique-categories {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--spacing-lg);
}

.category-card {
    background: var(--bg-surface);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    transition: all var(--transition-normal);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: transform var(--transition-normal);
}

.category-card:hover::before {
    transform: scaleX(1);
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.category-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-md);
    background: rgba(159, 198, 167, 0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-md);
    color: var(--accent-primary);
}

.category-icon svg {
    width: 24px;
    height: 24px;
}

.category-card h3 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xs);
}

.category-card > p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-md);
}

.technique-list {
    list-style: none;
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.technique-list li {
    padding: var(--spacing-xs) 0;
    color: var(--text-muted);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.technique-list li::before {
    content: '';
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--accent-primary);
    opacity: 0.5;
}

/* ========================================
   Dive Mode Section
   ======================================== */
.dive-mode {
    background: var(--gradient-dive);
    position: relative;
    overflow: hidden;
    padding: var(--spacing-2xl) 0;
}

.dive-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 20% 80%, rgba(74, 139, 156, 0.2) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(123, 181, 163, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.dive-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-2xl);
    align-items: center;
    position: relative;
    z-index: 1;
}

.dive-tag {
    background: rgba(74, 139, 156, 0.2);
    color: var(--dive-teal);
}

.dive-text h2 {
    font-size: clamp(2rem, 5vw, 3rem);
    margin-bottom: var(--spacing-md);
}

.dive-subtitle {
    color: var(--text-secondary);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-xl);
}

.dive-features {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.dive-feature {
    display: flex;
    gap: var(--spacing-md);
    align-items: flex-start;
}

.dive-feature-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-sm);
    background: rgba(74, 139, 156, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    color: var(--dive-teal);
}

.dive-feature-icon svg {
    width: 22px;
    height: 22px;
}

.dive-feature h4 {
    font-size: 1rem;
    margin-bottom: 2px;
}

.dive-feature p {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.safety-notice {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-xl);
    padding: var(--spacing-md);
    background: rgba(208, 163, 163, 0.1);
    border: 1px solid rgba(208, 163, 163, 0.2);
    border-radius: var(--radius-md);
    color: var(--dive-coral);
    font-size: 0.9rem;
}

.dive-visual {
    display: flex;
    align-items: center;
    justify-content: center;
}

.wave-animation {
    width: 280px;
    height: 280px;
}

.wave-circle {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: rgba(74, 139, 156, 0.2);
    border: 3px solid var(--dive-teal);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.wave-fill {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 65%;
    background: linear-gradient(180deg,
        rgba(74, 139, 156, 0.6) 0%,
        rgba(74, 139, 156, 0.3) 100%);
    animation: wave-rise 4s ease-in-out infinite;
}

.wave-fill::before {
    content: '';
    position: absolute;
    top: -10px;
    left: -50%;
    width: 200%;
    height: 20px;
    background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1200 120'%3E%3Cpath fill='rgba(74,139,156,0.3)' d='M0,60 C200,0 400,120 600,60 C800,0 1000,120 1200,60 V120 H0 Z'/%3E%3C/svg%3E") repeat-x;
    animation: wave-move 2s linear infinite;
}

@keyframes wave-rise {
    0%, 100% { height: 55%; }
    50% { height: 75%; }
}

@keyframes wave-move {
    0% { transform: translateX(0); }
    100% { transform: translateX(50%); }
}

.wave-content {
    position: relative;
    z-index: 1;
    text-align: center;
}

.wave-time {
    display: block;
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-primary);
}

.wave-label {
    font-size: 0.875rem;
    color: var(--dive-teal);
    text-transform: uppercase;
    letter-spacing: 2px;
}

/* ========================================
   Animations Section
   ======================================== */
.animations {
    background: var(--bg-surface);
}

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

.animation-card {
    background: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    border: 2px solid transparent;
}

.animation-card:hover,
.animation-card.active {
    border-color: var(--accent-primary);
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.animation-preview {
    height: 160px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-md);
}

/* Orb demo */
.orb-demo {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: radial-gradient(circle at 30% 30%,
        var(--accent-primary) 0%,
        rgba(159, 198, 167, 0.3) 70%,
        transparent 100%);
    box-shadow: 0 0 40px rgba(159, 198, 167, 0.5);
    animation: orb-breathe 4s ease-in-out infinite;
}

@keyframes orb-breathe {
    0%, 100% { transform: scale(0.8); }
    50% { transform: scale(1.1); }
}

/* Wave demo */
.wave-demo {
    width: 100%;
    height: 100px;
    overflow: hidden;
}

.wave-demo svg {
    width: 100%;
    height: 100%;
}

.wave-path {
    fill: rgba(159, 198, 167, 0.3);
    animation: wave-demo 3s ease-in-out infinite;
}

@keyframes wave-demo {
    0%, 100% { d: path("M0,45 Q25,25 50,45 T100,45 V60 H0 Z"); }
    50% { d: path("M0,25 Q25,45 50,25 T100,25 V60 H0 Z"); }
}

/* Ring demo */
.ring-demo {
    width: 100px;
    height: 100px;
}

.ring-demo svg {
    width: 100%;
    height: 100%;
    transform: rotate(-90deg);
}

.ring-bg {
    fill: none;
    stroke: var(--bg-surface);
    stroke-width: 6;
}

.ring-progress {
    fill: none;
    stroke: var(--accent-primary);
    stroke-width: 6;
    stroke-linecap: round;
    stroke-dasharray: 251;
    stroke-dashoffset: 251;
    animation: ring-fill 3s ease-in-out infinite;
}

@keyframes ring-fill {
    0%, 100% { stroke-dashoffset: 251; }
    50% { stroke-dashoffset: 50; }
}

.animation-card h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-xs);
}

.animation-card p {
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* ========================================
   Download Section
   ======================================== */
.download {
    background: var(--bg-primary);
    text-align: center;
}

.download-content {
    max-width: 600px;
    margin: 0 auto;
}

.download h2 {
    font-size: clamp(2rem, 5vw, 2.5rem);
    margin-bottom: var(--spacing-md);
}

.download p {
    color: var(--text-secondary);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-xl);
}

.download-buttons {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-surface);
    border-radius: var(--radius-md);
    transition: all var(--transition-normal);
    border: 1px solid var(--bg-elevated);
}

.download-btn:hover {
    background: var(--bg-elevated);
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}

.download-btn svg {
    width: 32px;
    height: 32px;
}

.download-btn div {
    text-align: left;
}

.download-btn span {
    font-size: 0.75rem;
    color: var(--text-muted);
    display: block;
}

.download-btn strong {
    font-size: 1.125rem;
}

/* ========================================
   Footer
   ======================================== */
.footer {
    background: var(--bg-surface);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 3fr;
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-xl);
}

.footer-brand .logo {
    margin-bottom: var(--spacing-md);
}

.footer-brand p {
    color: var(--text-muted);
    max-width: 280px;
}

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

.footer-column h4 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.footer-column a {
    display: block;
    color: var(--text-muted);
    padding: var(--spacing-xs) 0;
    font-size: 0.95rem;
    transition: color var(--transition-fast);
}

.footer-column a:hover {
    color: var(--accent-primary);
}

.footer-bottom {
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    justify-content: space-between;
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 968px) {
    .nav-links {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .dive-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .dive-features {
        align-items: center;
    }

    .dive-feature {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .safety-notice {
        flex-direction: column;
        text-align: center;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-brand {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

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

    .footer-bottom {
        flex-direction: column;
        align-items: center;
        gap: var(--spacing-sm);
    }
}

@media (max-width: 640px) {
    .hero-stats {
        gap: var(--spacing-lg);
    }

    .stat-number {
        font-size: 2rem;
    }

    .features-grid,
    .technique-categories,
    .animation-showcase {
        grid-template-columns: 1fr;
    }

    .footer-links {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .download-buttons {
        flex-direction: column;
        align-items: center;
    }

    .download-btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }
}

/* ========================================
   Legal Pages Styles
   ======================================== */
.legal-page {
    padding-top: 100px;
    min-height: 100vh;
}

.legal-content {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-md);
}

.legal-content h1 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.legal-content .last-updated {
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
}

.legal-content h2 {
    font-size: 1.5rem;
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
    color: var(--accent-primary);
}

.legal-content h3 {
    font-size: 1.125rem;
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
}

.legal-content p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.legal-content ul {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-lg);
}

.legal-content li {
    margin-bottom: var(--spacing-sm);
    line-height: 1.7;
}

.legal-content a {
    color: var(--accent-primary);
}

.legal-content a:hover {
    text-decoration: underline;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-muted);
    margin-bottom: var(--spacing-lg);
    transition: color var(--transition-fast);
}

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