/* ============================================
   DESIGN SYSTEM & CSS VARIABLES
   ============================================ */
:root {
    /* Color Palette - Vibrant Creative Studio */
    --color-primary: #6366f1;
    --color-primary-light: #818cf8;
    --color-primary-dark: #4f46e5;
    --color-accent: #ec4899;
    --color-accent-light: #f472b6;
    
    --color-bg: #0f0f14;
    --color-bg-elevated: #1a1a24;
    --color-bg-panel: #1e1e2e;
    --color-bg-input: #25253a;
    
    --color-text: #e9e9f0;
    --color-text-secondary: #a3a3b8;
    --color-text-muted: #6b6b7f;
    
    --color-border: #2a2a3f;
    --color-border-light: #35354f;
    
    /* Typography */
    --font-display: 'Syne', sans-serif;
    --font-body: 'DM Sans', sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    
    /* Shadows & Effects */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
    --shadow-glow: 0 0 24px rgba(99, 102, 241, 0.3);
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-body);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   LAYOUT
   ============================================ */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    position: relative;
}

.app-container::before {
    content: '';
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: 
        radial-gradient(circle at 20% 50%, rgba(99, 102, 241, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 50%, rgba(236, 72, 153, 0.08) 0%, transparent 50%);
    animation: bgFloat 20s ease-in-out infinite;
    pointer-events: none;
    z-index: 0;
}

@keyframes bgFloat {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    33% { transform: translate(3%, 3%) rotate(1deg); }
    66% { transform: translate(-2%, 2%) rotate(-1deg); }
}

/* ============================================
   HEADER
   ============================================ */
.app-header {
    padding: var(--spacing-xl) var(--spacing-2xl);
    border-bottom: 1px solid var(--color-border);
    background: rgba(15, 15, 20, 0.8);
    backdrop-filter: blur(20px);
    position: relative;
    z-index: 10;
    animation: slideDown 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xs);
}

.logo-icon {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.4);
}

.logo-spark {
    position: absolute;
    width: 6px;
    height: 6px;
    background: white;
    border-radius: 50%;
    animation: sparkle 2s ease-in-out infinite;
}

.logo-spark:nth-child(1) {
    top: 8px;
    left: 12px;
    animation-delay: 0s;
}

.logo-spark:nth-child(2) {
    top: 24px;
    right: 10px;
    animation-delay: 0.6s;
}

.logo-spark:nth-child(3) {
    bottom: 10px;
    left: 18px;
    animation-delay: 1.2s;
}

@keyframes sparkle {
    0%, 100% { 
        opacity: 0.3;
        transform: scale(1);
    }
    50% { 
        opacity: 1;
        transform: scale(1.5);
    }
}

.logo h1 {
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--color-text), var(--color-primary-light));
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
}

.tagline {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    font-weight: 500;
    margin-left: 62px;
}

/* ============================================
   MAIN CONTENT
   ============================================ */
.main-content {
    display: grid;
    grid-template-columns: 380px 1fr;
    gap: var(--spacing-lg);
    padding: var(--spacing-xl);
    flex: 1;
    position: relative;
    z-index: 1;
    animation: fadeIn 0.8s cubic-bezier(0.16, 1, 0.3, 1) 0.2s both;
}

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

/* ============================================
   CONTROLS PANEL
   ============================================ */
.controls-panel {
    background: var(--color-bg-panel);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
    height: fit-content;
    box-shadow: var(--shadow-lg);
    position: sticky;
    top: var(--spacing-xl);
}

.control-section {
    animation: slideInLeft 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.control-section:nth-child(1) { animation-delay: 0.1s; }
.control-section:nth-child(2) { animation-delay: 0.2s; }
.control-section:nth-child(3) { animation-delay: 0.3s; }
.control-section:nth-child(4) { animation-delay: 0.4s; }

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.section-title {
    font-family: var(--font-display);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.section-title .icon {
    font-size: 1.3rem;
}

/* Size Controls */
.size-controls {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.input-group label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.input-wrapper input {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    padding-right: 3rem;
    background: var(--color-bg-input);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    color: var(--color-text);
    font-size: 1rem;
    font-family: var(--font-body);
    font-weight: 600;
    transition: all var(--transition-base);
}

.input-wrapper input:focus {
    outline: none;
    border-color: var(--color-primary);
    background: var(--color-bg-elevated);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
}

.input-wrapper .unit {
    position: absolute;
    right: var(--spacing-md);
    color: var(--color-text-muted);
    font-size: 0.85rem;
    font-weight: 600;
    pointer-events: none;
}

/* Quick Sizes */
.quick-sizes {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xs);
}

.quick-size-btn {
    padding: var(--spacing-sm);
    background: var(--color-bg-input);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-sm);
    color: var(--color-text-secondary);
    font-size: 0.8rem;
    font-weight: 600;
    font-family: var(--font-body);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.quick-size-btn:hover {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
    transform: translateY(-2px);
}

/* Color Picker */
.color-picker-container input[type="color"] {
    width: 100%;
    height: 60px;
    border: 3px solid var(--color-border);
    border-radius: var(--radius-md);
    cursor: pointer;
    background: transparent;
    transition: all var(--transition-base);
}

.color-picker-container input[type="color"]::-webkit-color-swatch-wrapper {
    padding: 0;
}

.color-picker-container input[type="color"]::-webkit-color-swatch {
    border: none;
    border-radius: calc(var(--radius-md) - 3px);
}

.color-picker-container input[type="color"]:hover {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
}

.color-presets {
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    gap: var(--spacing-xs);
    margin-top: var(--spacing-md);
}

.color-preset {
    width: 100%;
    aspect-ratio: 1;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.color-preset::after {
    content: '';
    position: absolute;
    inset: -4px;
    border: 2px solid var(--color-primary);
    border-radius: calc(var(--radius-sm) + 2px);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.color-preset:hover::after,
.color-preset.active::after {
    opacity: 1;
}

.color-preset:hover {
    transform: scale(1.1);
}

/* Emoji Controls */
.emoji-picker-wrapper #emojiInput {
    width: 100%;
    padding: var(--spacing-md);
    background: var(--color-bg-input);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    color: var(--color-text);
    font-size: 1.5rem;
    text-align: center;
    font-family: var(--font-body);
    transition: all var(--transition-base);
    margin-bottom: var(--spacing-md);
}

.emoji-picker-wrapper #emojiInput:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
}

.emoji-presets {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.emoji-btn {
    padding: var(--spacing-md);
    background: var(--color-bg-input);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    font-size: 1.5rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.emoji-btn:hover {
    background: var(--color-primary);
    border-color: var(--color-primary);
    transform: scale(1.1);
}

.emoji-size-control {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.emoji-size-control label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-text-secondary);
}

.emoji-size-control input[type="range"] {
    width: 100%;
    height: 6px;
    background: var(--color-bg-input);
    border-radius: 3px;
    outline: none;
    appearance: none;
    -webkit-appearance: none;
}

.emoji-size-control input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.4);
    transition: all var(--transition-fast);
}

.emoji-size-control input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.emoji-size-control input[type="range"]::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    border: none;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.4);
}

/* Buttons */
.btn-primary,
.btn-secondary {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-size: 1rem;
    font-weight: 700;
    font-family: var(--font-display);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.2), transparent);
    opacity: 0;
    transition: opacity var(--transition-base);
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--color-bg-input);
    color: var(--color-text);
    border: 2px solid var(--color-border-light);
}

.btn-secondary:hover {
    background: var(--color-bg-elevated);
    border-color: var(--color-primary);
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.2);
}

.btn-secondary-variant {
    background: linear-gradient(135deg, var(--color-accent), #f472b6);
}

.download-controls {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

/* ============================================
   CANVAS AREA
   ============================================ */
.canvas-area {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.canvas-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.canvas-dimensions {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-text);
}

.canvas-hint {
    padding: var(--spacing-xs) var(--spacing-md);
    background: var(--color-bg-panel);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    color: var(--color-text-secondary);
    font-size: 0.85rem;
    font-weight: 600;
}

.canvas-wrapper {
    background: var(--color-bg-panel);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 600px;
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
}

.canvas-wrapper::before {
    content: '';
    position: absolute;
    inset: 0;
    background: 
        repeating-linear-gradient(
            0deg,
            transparent,
            transparent 19px,
            var(--color-border) 19px,
            var(--color-border) 20px
        ),
        repeating-linear-gradient(
            90deg,
            transparent,
            transparent 19px,
            var(--color-border) 19px,
            var(--color-border) 20px
        );
    opacity: 0.3;
    pointer-events: none;
}

#canvas {
    max-width: 100%;
    max-height: calc(100vh - 300px);
    box-shadow: 
        0 20px 60px rgba(0, 0, 0, 0.3),
        0 0 0 1px rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-sm);
    cursor: crosshair;
    position: relative;
    z-index: 1;
    transition: all var(--transition-slow);
}

#canvas:hover {
    box-shadow: 
        0 20px 60px rgba(99, 102, 241, 0.3),
        0 0 0 2px var(--color-primary);
}

.canvas-overlay {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 2;
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 1200px) {
    .main-content {
        grid-template-columns: 1fr;
    }
    
    .controls-panel {
        position: static;
    }
}

@media (max-width: 768px) {
    .app-header {
        padding: var(--spacing-lg);
    }
    
    .logo h1 {
        font-size: 1.5rem;
    }
    
    .tagline {
        margin-left: 56px;
        font-size: 0.85rem;
    }
    
    .main-content {
        padding: var(--spacing-md);
        gap: var(--spacing-md);
    }
    
    .controls-panel {
        padding: var(--spacing-lg);
    }
    
    .size-controls {
        grid-template-columns: 1fr;
    }
    
    .quick-sizes {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .canvas-wrapper {
        min-height: 400px;
        padding: var(--spacing-md);
    }
}