:root{--primary-color: #5b21b6;--secondary-color: #f59e0b;--background-light: #f3f4f6;--surface-light: #ffffff;--text-light: #1f2937;--border-light: #e5e7eb;--background-dark: #121212;--surface-dark: #1f2937;--surface-darker: #111827;--text-dark: #f3f4f6;--border-dark: #374151}body{margin:0;font-family:Inter,sans-serif;background-color:var(--background-light);color:var(--text-light);transition:background-color .3s,color .3s}.dark body{background-color:var(--background-dark);color:var(--text-dark)}.app-container{display:flex;justify-content:center;align-items:center;height:100vh;padding:1rem}.chat-card{width:100%;max-width:100rem;display:flex;flex-direction:column;background-color:var(--surface-light);border-radius:1rem;box-shadow:0 10px 15px -3px #0000001a,0 4px 6px -2px #0000000d;transition:background-color .3s,box-shadow .3s}.dark .chat-card{background-color:var(--surface-darker);box-shadow:none}.header{display:flex;justify-content:space-between;align-items:center;padding:1rem;background-color:var(--surface-darker);color:var(--text-dark);border-top-left-radius:1rem;border-top-right-radius:1rem;box-shadow:0 2px 4px #0000001a}.header-title{font-size:1.25rem;font-weight:700;text-align:center;flex-grow:1}.header-subtitle{font-size:.875rem;font-weight:400;text-align:center;opacity:.8}.theme-toggle-button{cursor:pointer;padding:.5rem;border-radius:9999px;background:none;border:none;color:var(--text-dark)}.theme-toggle-icon{width:1.5rem;height:1.5rem}.chat-area{flex-grow:1;overflow-y:auto;height:60vh;padding:1.5rem;background-color:var(--surface-light)}.dark .chat-area{background-color:var(--surface-darker)}.message{margin-bottom:1rem;max-width:80%;padding:.75rem 1rem;border-radius:.75rem;line-height:1.5}.user-message{align-self:flex-end;margin-left:auto;background-color:var(--primary-color);color:var(--text-dark);border-bottom-right-radius:.25rem}.bot-message{align-self:flex-start;margin-right:auto;background-color:var(--surface-dark);color:var(--text-dark);border-bottom-left-radius:.25rem;box-shadow:0 1px 3px #0000001a}.dark .bot-message{background-color:var(--surface-dark)}.message-content{white-space:pre-wrap}.feature-bar{display:flex;gap:.5rem;padding:1rem 1.5rem;background-color:var(--surface-light);border-top:1px solid var(--border-light)}.dark .feature-bar{background-color:var(--surface-darker);border-top:1px solid var(--border-dark)}.feature-button{display:flex;align-items:center;justify-content:center;flex:1;padding:.75rem 1rem;font-weight:600;border-radius:.5rem;cursor:pointer;transition:transform .1s,box-shadow .1s;border:none}.feature-button:hover{transform:translateY(-1px);box-shadow:0 4px 6px -1px #0000001a}.summarize-button{background-color:var(--primary-color);color:#fff}.experiment-button{background-color:var(--secondary-color);color:var(--text-dark)}.input-bar{padding:1rem 1.5rem 1.5rem;background-color:var(--surface-light);border-bottom-left-radius:1rem;border-bottom-right-radius:1rem}.dark .input-bar{background-color:var(--surface-darker)}.input-form{display:flex;gap:.5rem;border-radius:.75rem;background-color:var(--surface-light);box-shadow:0 4px 6px -1px #0000001a}.dark .input-form{background-color:var(--surface-dark);box-shadow:none}.text-input{flex-grow:1;padding:1rem;font-size:1rem;border:none;background:none;color:var(--text-light);resize:none;outline:none;border-radius:.75rem}.dark .text-input{color:var(--text-dark)}.send-button{display:flex;align-items:center;justify-content:center;padding:.75rem 1rem;background-color:var(--primary-color);color:#fff;border:none;border-radius:.75rem;cursor:pointer;transition:background-color .2s}.send-button:hover{background-color:#4c1d95}@media(max-width:640px){.chat-card,.header{border-radius:0}.input-bar{border-radius:0;padding:.75rem}.feature-bar{flex-direction:column;padding:.75rem}.feature-button{width:100%}.chat-area{height:70vh;padding:1rem}}