:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --background: #ffffff;
    --surface: #f8fafc;
    --border: #e2e8f0;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
        'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 2rem 1rem;
    color: var(--text-primary);
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    background: var(--background);
    border-radius: 1rem;
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 3rem 2rem;
    text-align: center;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.subtitle {
    font-size: 1.125rem;
    opacity: 0.95;
    margin-bottom: 1.5rem;
}

.links {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.links a {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    text-decoration: none;
    border-radius: 0.5rem;
    font-weight: 500;
    transition: all 0.2s;
    backdrop-filter: blur(10px);
}

.links a:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

main {
    padding: 2rem;
}

.converter {
    display: grid;
    gap: 1.5rem;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

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

.input-section,
.output-section {
    background: var(--surface);
    padding: 1.5rem;
    border-radius: 0.75rem;
    border: 1px solid var(--border);
}

textarea,
.output {
    width: 100%;
    min-height: 400px;
    padding: 1rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', 'Consolas', monospace;
    font-size: 0.875rem;
    line-height: 1.6;
    resize: vertical;
    background: var(--background);
    color: var(--text-primary);
    transition: border-color 0.2s;
}

textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.output {
    overflow-x: auto;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.controls {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    padding: 1rem 0;
}

.primary-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem 2rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0.5rem;
    font-size: 1.125rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: var(--shadow);
}

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

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

.primary-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-icon {
    font-size: 1.5rem;
    transition: transform 0.2s;
}

.primary-btn:hover .btn-icon {
    transform: translateX(4px);
}

.secondary-btn {
    padding: 0.5rem 1rem;
    background: var(--background);
    color: var(--text-secondary);
    border: 1px solid var(--border);
    border-radius: 0.375rem;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
}

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

#copyBtn .copied-text {
    display: none;
}

#copyBtn.copied .copy-text {
    display: none;
}

#copyBtn.copied .copied-text {
    display: inline;
}

#copyBtn.copied {
    background: var(--success-color);
    color: white;
    border-color: var(--success-color);
}

.status {
    font-size: 0.875rem;
    color: var(--text-secondary);
    min-height: 1.5rem;
}

.status.success {
    color: var(--success-color);
    font-weight: 500;
}

.status.error {
    color: #ef4444;
    font-weight: 500;
}

footer {
    background: var(--surface);
    padding: 2rem;
    text-align: center;
    border-top: 1px solid var(--border);
    color: var(--text-secondary);
}

footer p {
    margin-bottom: 0.5rem;
}

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

footer a:hover {
    text-decoration: underline;
}

.version {
    font-size: 0.875rem;
    opacity: 0.8;
}

#wasmStatus {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: var(--background);
    border-radius: 0.25rem;
    font-family: 'Monaco', 'Menlo', monospace;
    font-size: 0.75rem;
}

#wasmStatus.loaded {
    color: var(--success-color);
}

#wasmStatus.error {
    color: #ef4444;
}

/* Responsive Design */
@media (min-width: 768px) {
    body {
        padding: 3rem 2rem;
    }

    header h1 {
        font-size: 3rem;
    }

    main {
        padding: 3rem;
    }

    .converter {
        grid-template-columns: 1fr 1fr;
        grid-template-rows: auto auto;
    }

    .input-section {
        grid-column: 1;
        grid-row: 1;
    }

    .controls {
        grid-column: 1 / -1;
        grid-row: 2;
        flex-direction: row;
        justify-content: center;
    }

    .output-section {
        grid-column: 2;
        grid-row: 1;
    }
}

/* Loading Animation */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.primary-btn:disabled {
    animation: pulse 1.5s ease-in-out infinite;
}

/* Scrollbar Styling */
textarea::-webkit-scrollbar,
.output::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

textarea::-webkit-scrollbar-track,
.output::-webkit-scrollbar-track {
    background: var(--surface);
    border-radius: 4px;
}

textarea::-webkit-scrollbar-thumb,
.output::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

textarea::-webkit-scrollbar-thumb:hover,
.output::-webkit-scrollbar-thumb:hover {
    background: var(--secondary-color);
}