:root {
    --bg: #0d0d0d;
    --sidebar: #000000;
    --accent: #10a37f;
    --text-main: #e5e5e5;
    --border: rgba(255, 255, 255, 0.1);
    --input-bg: #212121;
}

* { box-sizing: border-box; transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1); }

body {
    font-family: 'Inter', sans-serif;
    margin: 0;
    background-color: var(--bg);
    color: var(--text-main);
    display: flex;
    height: 100vh;
    overflow: hidden;
}

.sidebar {
    width: 260px;
    background-color: var(--sidebar);
    display: flex;
    flex-direction: column;
    padding: 16px;
    border-right: 1px solid var(--border);
    z-index: 20;
}

.brand {
    display: flex; align-items: center; gap: 12px; font-size: 1.15rem; font-weight: 600; padding: 12px; margin-bottom: 24px; color: #fff;
}

.brand svg { width: 28px; height: 28px; color: var(--accent); }

.nav-btn {
    display: flex; align-items: center; gap: 12px; width: 100%; padding: 12px; background: transparent; border: 1px solid var(--border); color: #fff; border-radius: 12px; cursor: pointer; font-size: 0.9rem; margin-bottom: 12px;
}

.nav-btn:hover { background: rgba(255,255,255,0.05); transform: translateY(-1px); border-color: var(--accent); }

.action-group { margin-top: auto; display: flex; flex-direction: column; gap: 10px; }

.btn-action { text-decoration: none; text-align: center; padding: 12px; border-radius: 12px; font-size: 0.85rem; font-weight: 600; }

.btn-download { background: #fff; color: #000; }
.btn-web { background: #1a1a1a; color: #fff; border: 1px solid var(--border); }

.main-content { flex: 1; display: flex; flex-direction: column; position: relative; background: radial-gradient(circle at center, #151515 0%, #0d0d0d 100%); }

#welcomePage { position: absolute; top: 45%; left: 50%; transform: translate(-50%, -50%); text-align: center; width: 100%; max-width: 600px; z-index: 5; animation: fadeIn 0.8s ease; }

.welcome-logo { width: 80px; height: 80px; color: var(--accent); margin-bottom: 20px; animation: pulse 3s infinite ease-in-out; }

@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes pulse { 0%, 100% { transform: scale(1); } 50% { transform: scale(1.05); } }

#chatMessages { flex: 1; overflow-y: auto; padding: 60px 0 160px 0; display: flex; flex-direction: column; align-items: center; }

.msg-container { width: 100%; max-width: 760px; padding: 0 24px; margin-bottom: 32px; }
.msg.user { display: flex; justify-content: flex-end; }
.msg.user .msg-content { background: #2f2f2f; padding: 14px 22px; border-radius: 22px; }
.msg.ai .role-label { font-size: 0.75rem; font-weight: 700; color: var(--accent); margin-bottom: 8px; }
.msg-content { line-height: 1.6; color: #f0f0f0; white-space: pre-wrap; }

.streaming {
    background: linear-gradient(90deg, #fff 0%, var(--accent) 50%, #fff 100%);
    background-size: 200% auto; -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; animation: shimmer 2s linear infinite;
}

@keyframes shimmer { to { background-position: 200% center; } }

.input-outer { position: absolute; bottom: 35px; left: 50%; transform: translateX(-50%); width: 90%; max-width: 760px; }
.input-inner { background: var(--input-bg); border: 1px solid rgba(255,255,255,0.08); border-radius: 28px; padding: 8px 12px; display: flex; align-items: center; box-shadow: 0 12px 40px rgba(0,0,0,0.5); }

textarea { flex: 1; background: transparent; border: none; color: #fff; font-size: 1rem; outline: none; resize: none; padding: 12px; max-height: 200px; font-family: inherit; }

.btn-send { background: #fff; color: #000; border: none; width: 42px; height: 42px; border-radius: 50%; cursor: pointer; display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.btn-send.stop-state { background: #ff4a4a !important; color: #fff !important; border-radius: 12px; transform: scale(0.9); }