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

:root {
    --white: #ffffff;
    --off-white: #f7f9fb;
    --glass-white: rgba(255, 255, 255, 0.85);
    --glass-border: rgba(255, 255, 255, 0.6);
    --shadow-soft: rgba(0, 20, 40, 0.08);
    --shadow-hover: rgba(0, 20, 40, 0.12);
    --text-primary: #1a1a2e;
    --text-secondary: #4a4a5e;
    --focus-ring: rgba(100, 150, 255, 0.5);
    --glow-pink: rgba(255, 182, 193, 0.3);
    --glow-peach: rgba(255, 218, 185, 0.3);
    --glow-lilac: rgba(221, 160, 221, 0.3);
}

html, body {
    height: 100%;
    overflow-x: hidden;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: linear-gradient(135deg, var(--white) 0%, var(--off-white) 100%);
    background-attachment: fixed;
    color: var(--text-primary);
    line-height: 1.6;
    position: relative;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at center, transparent 0%, rgba(0, 10, 20, 0.02) 100%);
    pointer-events: none;
    z-index: 1;
}

body::after {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        repeating-linear-gradient(45deg, transparent, transparent 35px, rgba(255, 255, 255, 0.01) 35px, rgba(255, 255, 255, 0.01) 70px);
    opacity: 0.5;
    pointer-events: none;
    z-index: 1;
}

#fluid-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 2;
}

.motion-layer {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.blob, .wave, .spiral, .morph, .flow {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.03;
    will-change: transform, opacity;
}

.blob-1 {
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, var(--glow-pink), transparent);
    top: -200px;
    left: -200px;
    animation: blob 25s ease-in-out infinite;
}

.blob-2 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, var(--glow-peach), transparent);
    bottom: -150px;
    right: -150px;
    animation: blob 30s ease-in-out infinite reverse;
}

.wave-1 {
    width: 800px;
    height: 200px;
    background: linear-gradient(90deg, var(--glow-lilac), transparent);
    top: 50%;
    left: -400px;
    animation: wave 20s ease-in-out infinite;
}

.spiral-1 {
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, var(--glow-peach), transparent);
    top: 20%;
    right: 10%;
    animation: spiral 35s linear infinite;
}

.morph-1 {
    width: 400px;
    height: 400px;
    background: radial-gradient(ellipse, var(--glow-pink), transparent);
    bottom: 20%;
    left: 20%;
    animation: morph 40s ease-in-out infinite;
}

.flow-1 {
    width: 700px;
    height: 100px;
    background: linear-gradient(45deg, var(--glow-lilac), transparent);
    top: 70%;
    right: -350px;
    animation: flow 28s ease-in-out infinite;
}

@keyframes blob {
    0%, 100% {
        transform: translate(0, 0) scale(1);
        opacity: 0.03;
    }
    25% {
        transform: translate(100px, 50px) scale(1.1);
        opacity: 0.04;
    }
    50% {
        transform: translate(50px, 100px) scale(0.95);
        opacity: 0.02;
    }
    75% {
        transform: translate(150px, 20px) scale(1.05);
        opacity: 0.035;
    }
}

@keyframes wave {
    0%, 100% {
        transform: translateX(0) scaleY(1);
        opacity: 0.03;
    }
    50% {
        transform: translateX(calc(100vw + 400px)) scaleY(1.5);
        opacity: 0.02;
    }
}

@keyframes spiral {
    0% {
        transform: rotate(0deg) translateX(100px) rotate(0deg);
        opacity: 0.03;
    }
    100% {
        transform: rotate(360deg) translateX(100px) rotate(-360deg);
        opacity: 0.03;
    }
}

@keyframes morph {
    0%, 100% {
        border-radius: 50%;
        transform: scale(1) rotate(0deg);
        opacity: 0.03;
    }
    33% {
        border-radius: 40% 60% 70% 30%;
        transform: scale(1.15) rotate(120deg);
        opacity: 0.025;
    }
    66% {
        border-radius: 70% 30% 40% 60%;
        transform: scale(0.9) rotate(240deg);
        opacity: 0.035;
    }
}

@keyframes flow {
    0%, 100% {
        transform: translateX(0) skewX(0deg);
        opacity: 0.03;
    }
    25% {
        transform: translateX(-200px) skewX(-15deg);
        opacity: 0.02;
    }
    50% {
        transform: translateX(-calc(100vw + 350px)) skewX(0deg);
        opacity: 0.025;
    }
    75% {
        transform: translateX(-200px) skewX(15deg);
        opacity: 0.03;
    }
}

.container {
    position: relative;
    z-index: 10;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: clamp(1.5rem, 4vw, 3rem);
}

.headline {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 700;
    margin-bottom: clamp(2rem, 5vw, 4rem);
    text-align: center;
    background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
    animation: subtle-float 6s ease-in-out infinite;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

@keyframes subtle-float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-5px);
    }
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: clamp(1rem, 2.5vw, 2rem);
    width: 100%;
    max-width: 1000px;
}

.card {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: clamp(120px, 20vw, 200px);
    padding: clamp(1.5rem, 3vw, 3rem);
    text-decoration: none;
    color: var(--text-primary);
    background: var(--glass-white);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: clamp(16px, 3vw, 24px);
    box-shadow: 
        0 20px 40px var(--shadow-soft),
        inset 0 1px 1px rgba(255, 255, 255, 0.8),
        inset 0 -1px 1px rgba(255, 255, 255, 0.2);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    will-change: transform;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, 
        transparent, 
        rgba(255, 255, 255, 0.8) 50%, 
        transparent);
    opacity: 0.6;
}

.card::after {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    transform: rotate(45deg);
    transition: opacity 0.3s ease;
    opacity: 0;
    pointer-events: none;
}

.card:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 
        0 30px 60px var(--shadow-hover),
        0 0 40px var(--glow-pink),
        inset 0 1px 1px rgba(255, 255, 255, 0.9);
}

.card:hover::after {
    opacity: 1;
}

.card:focus-visible {
    outline: 3px solid var(--focus-ring);
    outline-offset: 4px;
}

.card:active {
    transform: translateY(-2px) scale(1.01);
}

.card-title {
    font-size: clamp(1.25rem, 2.5vw, 2rem);
    font-weight: 600;
    letter-spacing: -0.01em;
}

/* Very small mobile devices */
@media (max-width: 320px) {
    .card {
        min-height: 80px;
        padding: 1rem 0.75rem;
    }
    
    .card-title {
        font-size: 1.1rem;
    }
    
    .headline {
        font-size: 2rem;
        margin-bottom: 1.5rem;
    }
    
    .container {
        padding: 1rem;
    }
}

/* Mobile devices */
@media (max-width: 480px) {
    .cards-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .card {
        min-height: 100px;
        padding: 1.5rem 1rem;
        border-radius: 16px;
    }
    
    .card-title {
        font-size: 1.25rem;
    }
    
    .container {
        padding: 1.5rem;
    }
    
    .headline {
        font-size: 2.5rem;
        margin-bottom: 2rem;
    }
    
    /* Ensure minimum touch target size */
    .card {
        min-height: 100px; /* Minimum for comfortable touch */
    }
}

/* Small tablets */
@media (min-width: 481px) and (max-width: 768px) {
    .cards-grid {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }
    
    .card {
        min-height: 130px;
        padding: 2rem 1.5rem;
    }
}

/* Large tablets */
@media (min-width: 769px) and (max-width: 1024px) {
    .cards-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
    
    .card {
        min-height: 150px;
    }
}

/* Desktop */
@media (min-width: 1025px) {
    .cards-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 2rem;
    }
    
    .card {
        min-height: 200px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .blob, .wave, .spiral, .morph, .flow {
        animation: none !important;
        opacity: 0.02;
    }
    
    .headline {
        animation: none;
    }
    
    .card {
        transition: box-shadow 0.2s ease, outline 0.2s ease;
    }
    
    .card:hover {
        transform: none;
    }
    
    #fluid-canvas {
        display: none;
    }
}

/* Theme Toggle Button */
.theme-toggle {
    position: fixed;
    top: clamp(15px, 3vw, 20px);
    right: clamp(15px, 3vw, 20px);
    width: clamp(40px, 8vw, 44px);
    height: clamp(40px, 8vw, 44px);
    border: none;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    cursor: pointer;
    z-index: 1000;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    justify-content: center;
    touch-action: manipulation; /* Better touch responsiveness */
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: scale(1.05);
}

.theme-toggle:focus-visible {
    outline: 2px solid var(--focus-ring);
    outline-offset: 2px;
}

.theme-icon {
    width: clamp(16px, 3.5vw, 18px);
    height: clamp(16px, 3.5vw, 18px);
    border-radius: 50%;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    position: relative;
    transition: all 0.3s ease;
    margin: 0;
    flex-shrink: 0;
}

.theme-icon::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: calc(100% + 4px);
    height: calc(100% + 4px);
    border-radius: 50%;
    border: 2px solid transparent;
    background: linear-gradient(45deg, #1a1a2e, #16213e) padding-box, 
                linear-gradient(45deg, #4a4a5e, #2a2a3e) border-box;
    transition: all 0.3s ease;
}

/* Dark Mode Styles */
[data-theme="dark"] {
    --white: #0f1419;
    --off-white: #1a1f2e;
    --glass-white: rgba(26, 31, 46, 0.85);
    --glass-border: rgba(74, 84, 104, 0.3);
    --shadow-soft: rgba(0, 0, 0, 0.3);
    --shadow-hover: rgba(0, 0, 0, 0.4);
    --text-primary: #e8eaed;
    --text-secondary: #9aa0a6;
    --focus-ring: rgba(138, 180, 248, 0.5);
}

[data-theme="dark"] body {
    background: linear-gradient(135deg, #0f1419 0%, #1a1f2e 100%);
    color: var(--text-primary);
}

[data-theme="dark"] body::before {
    background: none;
}

[data-theme="dark"] body::after {
    background: none;
}

[data-theme="dark"] .theme-toggle {
    background: rgba(26, 31, 46, 0.3);
    border-color: rgba(74, 84, 104, 0.3);
}

[data-theme="dark"] .theme-toggle:hover {
    background: rgba(26, 31, 46, 0.4);
}

[data-theme="dark"] .theme-icon {
    background: linear-gradient(135deg, #ffd700 0%, #ffed4e 100%);
    box-shadow: 0 0 10px rgba(255, 215, 0, 0.3);
}

[data-theme="dark"] .theme-icon::before {
    background: linear-gradient(45deg, #ffd700, #ffed4e) padding-box, 
                linear-gradient(45deg, #ffed4e, #ffd700) border-box;
    transform: translate(-50%, -50%);
}

[data-theme="dark"] .card {
    background: rgba(26, 31, 46, 0.7);
    border-color: rgba(74, 84, 104, 0.3);
    color: var(--text-primary);
    box-shadow: 
        0 20px 40px rgba(0, 0, 0, 0.3),
        inset 0 1px 1px rgba(74, 84, 104, 0.1),
        inset 0 -1px 1px rgba(74, 84, 104, 0.05);
}

[data-theme="dark"] .card:hover {
    box-shadow: 
        0 30px 60px rgba(0, 0, 0, 0.4),
        0 0 40px rgba(74, 84, 104, 0.2),
        inset 0 1px 1px rgba(74, 84, 104, 0.15);
}

[data-theme="dark"] .headline {
    background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}