:root{--color-bg: #ffffff;--color-bg-elevated: #ffffff;--color-bg-surface: #ffffff;--color-bg-hover: #000000;--color-text: #000000;--color-text-muted: #000000;--color-text-subtle: #000000;--color-accent: #000000;--color-accent-hover: #ffffff;--color-accent-muted: rgba(0, 0, 0, .15);--color-border: #000000;--color-success: #000000;--color-error: #000000;--font-sans: "Work Sans", system-ui, sans-serif;--font-mono: "IBM Plex Mono", monospace;--space-xs: .25rem;--space-sm: .5rem;--space-md: 1rem;--space-lg: 1.5rem;--space-xl: 2rem;--space-2xl: 3rem;--max-width: 1200px;--transition-fast: .15s ease;--transition-base: .25s ease}*,*:before,*:after{box-sizing:border-box}html{font-size:16px;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{margin:0;padding:0;font-family:var(--font-sans);font-weight:400;line-height:1.6;color:var(--color-text);background-color:var(--color-bg);min-height:100vh}.app{max-width:var(--max-width);margin:0 auto;padding:var(--space-xl);min-height:100vh;display:flex;flex-direction:column}.header{margin-bottom:var(--space-2xl);animation:fadeInDown .6s ease-out}.title{font-size:2.5rem;font-weight:700;margin:0 0 var(--space-sm);letter-spacing:-.02em;display:flex;align-items:center;gap:var(--space-md);line-height:1}.title-icon{display:inline-flex;align-items:center;justify-content:center;width:56px;height:56px;background:var(--color-accent-muted);font-size:1.5rem;border-radius:50%}.subtitle{margin:0;font-size:1.125rem;color:var(--color-text-muted);font-weight:300}.instructions{background:var(--color-bg-elevated);border:1px solid var(--color-border);padding:var(--space-lg);margin-bottom:var(--space-xl);animation:fadeInUp .6s ease-out .1s both}.section-title{font-size:1rem;font-weight:600;margin:0 0 var(--space-md);text-transform:uppercase;letter-spacing:.1em;color:var(--color-accent)}.steps{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:var(--space-md)}.steps li{display:flex;align-items:flex-start;gap:var(--space-md)}.step-number{flex-shrink:0;width:28px;height:28px;display:flex;align-items:center;justify-content:center;background:var(--color-accent-muted);color:var(--color-accent);border-radius:50%;font-size:.875rem;font-weight:600}.step-text{color:var(--color-text-muted);font-size:.9375rem}.converter-grid{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-lg);flex:1;min-height:400px}@media(max-width:768px){.converter-grid{grid-template-columns:1fr}}.panel{display:flex;flex-direction:column;background:var(--color-bg-elevated);border:1px solid var(--color-border);overflow:hidden}.input-panel{animation:fadeInUp .6s ease-out .2s both}.output-panel{animation:fadeInUp .6s ease-out .3s both}.panel-header{display:flex;align-items:center;justify-content:space-between;padding:var(--space-md) var(--space-lg);border-bottom:1px solid var(--color-border);background:var(--color-bg-surface)}.panel-title{margin:0;font-size:.875rem;font-weight:600;text-transform:uppercase;letter-spacing:.05em}.panel-hint{font-size:.8125rem;color:var(--color-text-subtle)}.status{font-size:.8125rem;font-weight:500}.status.success{color:var(--color-success)}.status.error{color:var(--color-error)}.code-input,.code-output{flex:1;width:100%;padding:var(--space-lg);font-family:var(--font-mono);font-size:.875rem;line-height:1.7;color:var(--color-text);background:var(--color-bg);border:none;resize:none;outline:none}.code-input::placeholder,.code-output::placeholder{color:var(--color-text-subtle)}.code-input:focus,.code-output:focus{background:var(--color-bg)}.code-output{background:var(--color-bg);cursor:text}.panel-actions{display:flex;gap:var(--space-sm);padding:var(--space-md) var(--space-lg);border-top:1px solid var(--color-border);background:var(--color-bg-surface)}.btn{display:inline-flex;align-items:center;gap:var(--space-sm);padding:var(--space-sm) var(--space-md);font-family:var(--font-sans);font-size:.875rem;font-weight:500;border:1px solid transparent;cursor:pointer;transition:all var(--transition-fast)}.btn:disabled{opacity:.5;cursor:not-allowed}.btn-icon{font-size:1em}.btn-primary{background:var(--color-accent);color:var(--color-bg);border-color:var(--color-accent)}.btn-primary:hover:not(:disabled){background:var(--color-bg);color:var(--color-accent);border-color:var(--color-accent);transform:translateY(-1px)}.btn-primary:active:not(:disabled){transform:translateY(0)}.btn-ghost{background:transparent;color:var(--color-text-muted);border:1px solid var(--color-border)}.btn-ghost:hover:not(:disabled){background:var(--color-accent);color:var(--color-bg);border-color:var(--color-accent)}.footer{text-align:center;padding-top:var(--space-xl);margin-top:auto;animation:fadeInUp .6s ease-out .4s both}.footer p{margin:0;font-size:.875rem;color:var(--color-text-subtle)}.toast{position:fixed;top:var(--space-xl);left:50%;transform:translate(-50%) translateY(-100px);padding:var(--space-md) var(--space-lg);background:var(--color-bg-surface);border:1px solid var(--color-border);font-size:.875rem;color:var(--color-text);opacity:0;visibility:hidden;transition:all var(--transition-base);z-index:1000}.toast.visible{opacity:1;visibility:visible;transform:translate(-50%) translateY(0)}.toast.success{border-color:var(--color-success);color:var(--color-success)}.toast.error{border-color:var(--color-error);color:var(--color-error)}@keyframes fadeInDown{0%{opacity:0;transform:translateY(-20px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}::selection{background:var(--color-accent-muted);color:var(--color-text)}