:root{--primary-color: #4caf50;--secondary-color: #e8f5e9;--accent-color: #81c784;--text-color: #38a581;--background-color: #f9fff9;--input-bg: #ffffff;--card-bg: #ffffff;--border-color: #c8e6c9}.dark-theme{--primary-color: #2e7d32;--secondary-color: #1b1b1b;--accent-color: #66bb6a;--text-color: #eafffc;--background-color: #121212;--input-bg: #2c2c2c;--card-bg: #1f1f1f;--border-color: #424242}body{background-color:var(--background-color);color:var(--text-color);font-family:Segoe UI,Roboto,sans-serif;transition:background-color .3s ease,color .3s ease;min-height:100vh}input,select,textarea{background-color:var(--input-bg);border:1px solid var(--border-color);color:var(--text-color);transition:all .3s ease-in-out}input:focus,select:focus,textarea:focus{border-color:var(--accent-color);outline:none;box-shadow:0 0 5px var(--accent-color)}.card,.results,.history,.result-container{background-color:var(--card-bg);color:var(--text-color);border-radius:.4rem;box-shadow:0 2px 8px #0003;transition:background-color .3s ease,color .3s ease}button{transition:all .3s ease}.theme-toggle{background:none;border:1px solid currentColor;border-radius:.4rem;padding:.4rem .8rem;cursor:pointer;font-weight:700;transition:all .3s ease-in-out}.theme-toggle:hover{opacity:.8;background-color:var(--accent-color);color:#fff}