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

:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --bg-color: #0f172a;
    --surface-color: #1e293b;
    --surface-hover: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --success-color: #22c55e;
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -2px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -4px rgba(0, 0, 0, 0.2);
}

html {
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

/* App Container */
.app-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, #6366f1, #8b5cf6, #d946ef);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
}

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

/* Main Content */
main {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

/* Section Styles */
.section {
    background: var(--surface-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow);
}

.section h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

/* Color Input Section */
.color-input-wrapper {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    align-items: center;
}

.color-picker-container {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.color-picker-container input[type="color"] {
    width: 60px;
    height: 60px;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    padding: 0;
    background: none;
}

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

.color-picker-container input[type="color"]::-webkit-color-swatch {
    border: 3px solid var(--border-color);
    border-radius: var(--radius-md);
}

.color-picker-container label {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.hex-input-container {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.hex-input-container label {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.hex-input-container input {
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-color);
    color: var(--text-primary);
    font-size: 1rem;
    font-family: 'SF Mono', 'Fira Code', monospace;
    width: 140px;
    transition: border-color 0.2s ease;
}

.hex-input-container input:focus {
    outline: none;
    border-color: var(--primary-color);
}

/* Harmony Buttons */
.harmony-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.harmony-btn {
    padding: 0.625rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-color);
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.harmony-btn:hover {
    border-color: var(--primary-color);
    color: var(--text-primary);
}

.harmony-btn.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

/* Gradient Settings */
.settings-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

.setting-item {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.setting-item label {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.setting-item select {
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-color);
    color: var(--text-primary);
    font-size: 1rem;
    cursor: pointer;
    transition: border-color 0.2s ease;
}

.setting-item select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.setting-item input[type="range"] {
    width: 100%;
    height: 8px;
    border-radius: 4px;
    background: var(--bg-color);
    appearance: none;
    cursor: pointer;
}

.setting-item input[type="range"]::-webkit-slider-thumb {
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    transition: transform 0.2s ease;
}

.setting-item input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.1);
}

.setting-item input[type="range"]::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
}

/* Preview Section */
.preview-options {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.preview-btn {
    padding: 0.5rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-color);
    color: var(--text-secondary);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.preview-btn:hover {
    border-color: var(--primary-color);
    color: var(--text-primary);
}

.preview-btn.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.preview-container {
    border-radius: var(--radius-md);
    overflow: hidden;
}

.gradient-preview {
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.gradient-preview.full-preview {
    width: 100%;
    height: 200px;
    border-radius: var(--radius-md);
}

.gradient-preview.card-preview {
    width: 300px;
    height: 180px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    margin: 2rem auto;
}

.gradient-preview.button-preview {
    width: 200px;
    height: 50px;
    border-radius: 25px;
    margin: 2rem auto;
    box-shadow: var(--shadow);
}

.gradient-preview.text-preview {
    background: transparent !important;
    height: auto;
    padding: 2rem;
}

.gradient-preview.text-preview .preview-text {
    font-size: 3rem;
    font-weight: 800;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.preview-content {
    text-align: center;
}

.preview-text {
    color: white;
    font-size: 1.25rem;
    font-weight: 600;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

/* Harmony Colors Display */
.harmony-colors-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 1rem;
}

.color-swatch {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.swatch-color {
    width: 100%;
    aspect-ratio: 1;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow);
    cursor: pointer;
    transition: transform 0.2s ease;
    position: relative;
}

.swatch-color:hover {
    transform: scale(1.05);
}

.swatch-color::after {
    content: 'Click to copy';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    font-size: 0.7rem;
    padding: 0.25rem;
    text-align: center;
    border-radius: 0 0 var(--radius-md) var(--radius-md);
    opacity: 0;
    transition: opacity 0.2s ease;
}

.swatch-color:hover::after {
    opacity: 1;
}

.swatch-hex {
    font-family: 'SF Mono', 'Fira Code', monospace;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Code Display Section */
.code-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.code-tab {
    padding: 0.5rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-color);
    color: var(--text-secondary);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.code-tab:hover {
    border-color: var(--primary-color);
    color: var(--text-primary);
}

.code-tab.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.code-output-container {
    position: relative;
}

.code-output {
    background: var(--bg-color);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    font-family: 'SF Mono', 'Fira Code', monospace;
    font-size: 0.875rem;
    color: var(--text-primary);
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-all;
    min-height: 100px;
    max-height: 300px;
}

.copy-btn {
    position: absolute;
    top: 0.75rem;
    right: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 0.75rem;
    border: none;
    border-radius: var(--radius-sm);
    background: var(--surface-color);
    color: var(--text-secondary);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.copy-btn:hover {
    background: var(--surface-hover);
    color: var(--text-primary);
}

.copy-btn.copied {
    background: var(--success-color);
    color: white;
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--success-color);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1000;
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem 1rem;
    margin-top: 2rem;
    border-top: 1px solid var(--border-color);
}

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

footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

footer a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .app-container {
        padding: 1rem;
    }

    header h1 {
        font-size: 1.75rem;
    }

    .subtitle {
        font-size: 1rem;
    }

    .section {
        padding: 1rem;
    }

    .section h2 {
        font-size: 1.125rem;
    }

    .color-input-wrapper {
        flex-direction: column;
        align-items: flex-start;
    }

    .harmony-buttons {
        gap: 0.5rem;
    }

    .harmony-btn {
        padding: 0.5rem 0.75rem;
        font-size: 0.8rem;
    }

    .settings-grid {
        grid-template-columns: 1fr;
    }

    .gradient-preview.full-preview {
        height: 150px;
    }

    .gradient-preview.card-preview {
        width: 100%;
        max-width: 280px;
    }

    .gradient-preview.text-preview .preview-text {
        font-size: 2rem;
    }

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

    .code-tabs {
        gap: 0.25rem;
    }

    .code-tab {
        padding: 0.4rem 0.6rem;
        font-size: 0.75rem;
    }

    .code-output {
        font-size: 0.75rem;
        padding: 0.75rem;
    }
}

@media (max-width: 480px) {
    header h1 {
        font-size: 1.5rem;
    }

    .harmony-colors-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .preview-options {
        gap: 0.25rem;
    }

    .preview-btn {
        padding: 0.4rem 0.6rem;
        font-size: 0.75rem;
    }
}