@import "https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Noto+Sans+SC:wght@400;500;700&display=swap";:root{--primary:#00a86b;--primary-light:#3dcc94;--primary-dark:#007a4d;--bg-color:#f4f9f6;--card-bg:#ffffffd9;--text-main:#1f2937;--text-light:#6b7280;--shadow-sm:0 4px 6px -1px #00a86b1a, 0 2px 4px -1px #00a86b0f;--shadow-md:0 10px 15px -3px #00a86b1a, 0 4px 6px -2px #00a86b0d;--shadow-lg:0 20px 25px -5px #00a86b26, 0 10px 10px -5px #00a86b0a;--border-radius:16px;--glass-border:1px solid #ffffff80}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--bg-color);color:var(--text-main);-webkit-font-smoothing:antialiased;background-image:radial-gradient(at 0 0,#a3ffd433 0,#0000 50%),radial-gradient(at 100% 100%,#a3ffd433 0,#0000 50%);background-attachment:fixed;min-height:100vh;font-family:Inter,Noto Sans SC,sans-serif}.glass{background:var(--card-bg);-webkit-backdrop-filter:blur(12px);border:var(--glass-border);box-shadow:var(--shadow-md);border-radius:var(--border-radius)}.flashcard-container{perspective:1000px;width:100%;max-width:320px;height:400px;margin:0 auto}.flashcard{width:100%;height:100%;transform-style:preserve-3d;cursor:pointer;transition:transform .6s cubic-bezier(.4,.2,.2,1);position:relative}.flashcard.flipped{transform:rotateY(180deg)}.flashcard-face{backface-visibility:hidden;text-align:center;flex-direction:column;justify-content:center;align-items:center;width:100%;height:100%;padding:2rem;display:flex;position:absolute}.flashcard-front{background:linear-gradient(135deg,#fff 0%,#f0fdf4 100%)}.flashcard-back{color:#fff;background:linear-gradient(135deg,#00a86b 0%,#007a4d 100%);transform:rotateY(180deg)}.flashcard .hanzi{text-shadow:2px 2px 4px #0000001a;margin-bottom:1rem;font-family:Noto Sans SC,sans-serif;font-size:5rem;font-weight:700}.flashcard-back .pinyin{opacity:.9;margin-bottom:.5rem;font-size:2rem;font-weight:500}.flashcard-back .meaning{opacity:.8;font-size:1.25rem}.btn-primary{background-color:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:999px;align-items:center;gap:.5rem;padding:.75rem 1.5rem;font-size:1rem;font-weight:600;transition:all .2s;display:inline-flex;box-shadow:0 4px 14px #00a86b4d}.btn-primary:hover{background-color:var(--primary-light);transform:translateY(-2px);box-shadow:0 6px 20px #00a86b66}.btn-icon{cursor:pointer;width:48px;height:48px;color:inherit;background:#fff3;border:none;border-radius:50%;justify-content:center;align-items:center;transition:all .2s;display:flex}.btn-icon:hover{background:#ffffff4d;transform:scale(1.1)}.chat-container{flex-direction:column;gap:1.5rem;padding:1.5rem;display:flex}.chat-bubble{border-radius:20px;max-width:80%;padding:1rem 1.5rem;animation:.3s forwards fadeIn;position:relative}.chat-bubble.speaker-A{box-shadow:var(--shadow-sm);background-color:#fff;border-bottom-left-radius:4px;align-self:flex-start}.chat-bubble.speaker-B{background-color:var(--primary);color:#fff;border-bottom-right-radius:4px;align-self:flex-end;box-shadow:0 4px 14px #00a86b33}.chat-bubble .pinyin{opacity:.7;margin-bottom:.25rem;font-size:.875rem}.chat-bubble.speaker-B .pinyin{opacity:.9}.chat-bubble .hanzi{font-family:Noto Sans SC,sans-serif;font-size:1.5rem;font-weight:500}.chat-bubble .meaning{opacity:.6;border-top:1px solid #0000000d;margin-top:.5rem;padding-top:.5rem;font-size:.875rem}.chat-bubble.speaker-B .meaning{opacity:.8;border-top-color:#fff3}.app-container{max-width:800px;margin:0 auto;padding:2rem 1rem}.header{text-align:center;margin-bottom:3rem}.header h1{color:var(--primary-dark);margin-bottom:.5rem;font-size:2.5rem}.header p{color:var(--text-light);font-size:1.1rem}.tabs{justify-content:center;gap:1rem;margin-bottom:2rem;display:flex}.tab-btn{color:var(--text-light);cursor:pointer;background:0 0;border:2px solid #0000;border-radius:999px;padding:.75rem 2rem;font-weight:600;transition:all .3s}.tab-btn.active{color:var(--primary);box-shadow:var(--shadow-sm);background:#fff}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.combinations-table{border-collapse:collapse;text-align:center;width:100%;box-shadow:var(--shadow-sm);background:#fff;border-radius:12px;overflow:hidden}.combinations-table th{color:var(--primary-dark);background:#00a86b1a;border:1px solid #0000000d;padding:1rem;font-weight:600}.combinations-table td{border:1px solid #0000000d;padding:.5rem}.syllable-btn{color:var(--text-main);cursor:pointer;background:0 0;border:1px solid #0000;border-radius:6px;width:100%;padding:.5rem 1rem;font-size:1.1rem;font-weight:500;transition:all .2s}.syllable-btn:hover{background:var(--primary);color:#fff;transform:scale(1.05)}