/* ═══════════════════════════════════════════════
   maid Ngáo — CSS
   Fix: input area luôn hiển thị ở cuối trang
   ═══════════════════════════════════════════════ */

:root {
    --bg-deep:      #0d0d1a;
    --bg-panel:     #12102b;
    --bg-card:      #1a1835;
    --bg-input:     #1e1c3a;
    --accent:       #7c3aed;
    --accent-light: #a78bfa;
    --accent-glow:  rgba(124,58,237,0.2);
    --green:        #4ade80;
    --red:          #f87171;
    --text-1:       #f0eeff;
    --text-2:       #9d9bc4;
    --text-3:       #4a4870;
    --border:       rgba(139,92,246,0.18);
    --border-hi:    rgba(139,92,246,0.45);
    --bot-bg:       rgba(255,255,255,0.06);
    --user-bg:      linear-gradient(135deg,#7c3aed,#a78bfa);
    --sidebar-w:    250px;
    --r:            16px;
    --r-sm:         10px;
    --r-pill:       999px;
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}

html,body{
    height: calc(var(--vh, 1vh) * 100); /* Thay cho height: 100% */
    overflow: hidden;
    font-family:'Be Vietnam Pro',system-ui,sans-serif;
    background:var(--bg-deep);
    color:var(--text-1);
    font-size:15px;
    line-height:1.6;
    -webkit-font-smoothing:antialiased;
}

/* ── APP SHELL: sidebar + main cạnh nhau, đúng chiều cao màn hình ── */
.app{
    display: flex;
    height: calc(var(--vh, 1vh) * 100); /* Thay cho height: 100vh */
    overflow: hidden;
}

/* ════════════ SIDEBAR ════════════ */
.sidebar{
    width:var(--sidebar-w);
    min-width:var(--sidebar-w);
    background:var(--bg-panel);
    border-right:1px solid var(--border);
    display:flex;
    flex-direction:column;
    overflow:hidden;
    flex-shrink:0;
    transition:transform .3s ease;
}

.sidebar-brand{
    display:flex;align-items:center;gap:10px;
    padding:18px 14px 14px;
    border-bottom:1px solid var(--border);
    flex-shrink:0;
}
.brand-icon{font-size:26px;filter:drop-shadow(0 0 8px rgba(167,139,250,.6))}
.brand-name{font-family:'Space Grotesk',sans-serif;font-weight:700;font-size:17px}
.brand-tag{font-size:11px;color:var(--accent-light);font-weight:500}
.brand-info{display:flex;flex-direction:column}

.bot-status{
    display:flex;align-items:center;gap:10px;
    padding:14px;border-bottom:1px solid var(--border);flex-shrink:0;
}
.status-avatar{position:relative;flex-shrink:0}
.status-avatar img{width:42px;height:42px;border-radius:50%;border:2px solid var(--accent);background:var(--bg-card);display:block}
.status-dot{position:absolute;bottom:0;right:0;width:11px;height:11px;border-radius:50%;border:2px solid var(--bg-panel)}
.status-dot.online{background:var(--green)}
.status-info{display:flex;flex-direction:column}
.status-name{font-weight:600;font-size:13px}
.status-text{font-size:12px;color:var(--green)}

.sidebar-nav{flex:1;padding:10px 8px;display:flex;flex-direction:column;gap:3px;overflow:hidden}
.nav-btn{
    display:flex;align-items:center;gap:9px;
    padding:9px 11px;border:none;background:transparent;
    color:var(--text-2);font-size:14px;font-weight:500;
    border-radius:var(--r-sm);cursor:pointer;width:100%;text-align:left;
    font-family:'Be Vietnam Pro',sans-serif;
    transition:all .2s;
}
.nav-btn:hover{background:var(--bg-card);color:var(--text-1)}
.nav-btn.active{background:var(--accent-glow);color:var(--accent-light);box-shadow:inset 0 0 0 1px rgba(139,92,246,.25)}
.nav-icon{font-size:17px;flex-shrink:0}

.sidebar-footer{padding:10px 8px;border-top:1px solid var(--border);flex-shrink:0;display:flex;flex-direction:column;gap:8px}
.clear-btn{
    width:100%;padding:8px 12px;background:transparent;
    border:1px solid rgba(248,113,113,.3);color:var(--red);
    border-radius:var(--r-sm);font-family:'Be Vietnam Pro',sans-serif;
    font-size:13px;cursor:pointer;transition:all .2s;
}
.clear-btn:hover{background:rgba(248,113,113,.1)}

.mode-toggle-btn{
    width:100%;padding:8px 12px;background:transparent;
    border:1px solid var(--border);color:var(--text-2);
    border-radius:var(--r-sm);font-family:'Be Vietnam Pro',sans-serif;
    font-size:13px;cursor:pointer;transition:all .2s;
    display:flex;align-items:center;justify-content:center;gap:6px;
}
.mode-toggle-btn:hover{border-color:var(--border-hi);color:var(--text-1)}
.mode-toggle-btn.active{
    background:var(--accent-glow);color:var(--accent-light);
    border-color:rgba(139,92,246,.4);box-shadow:inset 0 0 0 1px rgba(139,92,246,.25);
}

/* ════════════ MAIN ════════════ */
.main{
    flex:1;
    min-width:0;
    display:flex;
    flex-direction:column;
    overflow:hidden;
    height: calc(var(--vh, 1vh) * 100); /* Thay cho height: 100vh */
}

/* ── Panel: ẩn mặc định, dùng flex khi active ── */
.panel {
    display: none;
    flex-direction: column;
    height: 100%;
    flex: 1;
    min-height: 0;
    overflow: hidden;
}
.panel.active{display:flex}

/* ════════════ CHAT PANEL ════════════ */
.chat-header{
    display:flex;align-items:center;justify-content:space-between;
    padding:13px 18px;
    background:var(--bg-panel);
    border-bottom:1px solid var(--border);
    flex-shrink:0;
}
.chat-header-left{display:flex;align-items:center;gap:10px}
.menu-toggle{
    display:none;background:none;border:none;
    color:var(--text-2);font-size:20px;cursor:pointer;
    padding:4px;border-radius:var(--r-sm);
}
.header-bot-info{display:flex;flex-direction:column}
.header-name{font-family:'Space Grotesk',sans-serif;font-weight:700;font-size:16px}
.header-status{font-size:12px;color:var(--green);display:flex;align-items:center;gap:5px}

.pulse{
    display:inline-block;width:7px;height:7px;
    background:var(--green);border-radius:50%;
    animation:pulse-anim 1.5s ease-in-out infinite;
}
@keyframes pulse-anim{
    0%,100%{opacity:1;transform:scale(1)}
    50%{opacity:.5;transform:scale(.8)}
}

.icon-btn{
    background:var(--bg-card);border:1px solid var(--border);
    color:var(--text-2);width:36px;height:36px;
    border-radius:var(--r-sm);cursor:pointer;font-size:15px;
    transition:all .2s;display:flex;align-items:center;justify-content:center;
}
.icon-btn:hover{border-color:var(--border-hi);color:var(--text-1)}

/* Messages - phần duy nhất cuộn */
.chat-messages {
    flex: 1;
    min-height: 0;
    overflow-y: auto;
    padding: 18px 16px;
    display: flex;
    flex-direction: column;
    gap: 14px;
    scroll-behavior: smooth;
}

.chat-messages::-webkit-scrollbar{width:4px}
.chat-messages::-webkit-scrollbar-track{background:transparent}
.chat-messages::-webkit-scrollbar-thumb{background:var(--text-3);border-radius:2px}

/* Message bubbles */
.message{
    display:flex;align-items:flex-end;gap:9px;
    animation:msg-in .28s ease;
}
@keyframes msg-in{
    from{opacity:0;transform:translateY(8px)}
    to{opacity:1;transform:translateY(0)}
}
.user-message{flex-direction:row-reverse}

.msg-avatar{
    width:34px;height:34px;border-radius:50%;
    background:var(--bg-card);border:1.5px solid var(--border);
    display:flex;align-items:center;justify-content:center;
    font-size:16px;flex-shrink:0;
}
.msg-avatar.user-pi-avatar{
    background:linear-gradient(135deg,#7c3aed,#a78bfa);
    border:none;color:#fff;font-weight:700;font-size:12.5px;
    font-family:'Space Grotesk',sans-serif;
}

.msg-content{
    display:flex;flex-direction:column;gap:3px;
    max-width:70%;
}
.user-message .msg-content{align-items:flex-end}

.msg-bubble{
    padding:10px 14px;
    font-size:14.5px;line-height:1.55;
    word-break:break-word;
}
.bot-message .msg-bubble{
    background:var(--bot-bg);
    border:1px solid var(--border);
    border-radius:18px 18px 18px 4px;
    color:var(--text-1);
}
.user-message .msg-bubble{
    background:var(--user-bg);
    border-radius:18px 18px 4px 18px;
    color:#fff;
    box-shadow:0 2px 16px rgba(124,58,237,.35);
}
.msg-time{font-size:11px;color:var(--text-3);padding:0 3px}

/* Typing dots */
.typing-bubble{
    background:var(--bot-bg);
    border:1px solid var(--border);
    border-radius:18px 18px 18px 4px;
    padding:13px 17px;
    display:flex;align-items:center;gap:5px;
}
.typing-bubble .dot{
    width:8px;height:8px;background:var(--text-2);border-radius:50%;
    animation:dot-bounce 1.2s ease-in-out infinite;
}
.typing-bubble .dot:nth-child(2){animation-delay:.2s}
.typing-bubble .dot:nth-child(3){animation-delay:.4s}
@keyframes dot-bounce{
    0%,60%,100%{transform:translateY(0);opacity:.4}
    30%{transform:translateY(-7px);opacity:1}
}

/* Quick suggestions */
.suggestions{
    padding:8px 16px 4px;
    display:flex;gap:7px;
    flex-wrap:nowrap;overflow-x:auto;
    flex-shrink:0;
}
.suggestions::-webkit-scrollbar{display:none}
.suggestion-chip{
    padding:6px 13px;
    background:var(--bg-card);border:1px solid var(--border);
    color:var(--text-2);border-radius:var(--r-pill);
    font-size:13px;font-family:'Be Vietnam Pro',sans-serif;
    cursor:pointer;white-space:nowrap;transition:all .2s;
}
.suggestion-chip:hover{border-color:var(--accent);color:var(--accent-light);background:var(--accent-glow)}

/* INPUT AREA - Cập nhật để luôn ở dưới cùng */
.chat-input-area{
    padding:10px 14px 14px;
    border-top:1px solid var(--border);
    background:var(--bg-panel);
    flex-shrink:0;
    margin-top: auto; /* Đẩy khu vực này sát đáy */
}

.input-wrapper{
    display:flex;
    align-items:flex-end;
    gap:9px;
    background:var(--bg-input);
    border:1.5px solid var(--border);
    border-radius:20px;
    padding:9px 9px 9px 16px;
    transition:border-color .2s,box-shadow .2s;
}
.input-wrapper:focus-within{
    border-color:var(--accent);
    box-shadow:0 0 0 3px var(--accent-glow);
}

textarea#messageInput{
    flex:1;
    background:none;border:none;outline:none;
    color:var(--text-1);
    font-family:'Be Vietnam Pro',sans-serif;
    font-size:15px;
    resize:none;
    line-height:1.5;
    max-height:110px;
    overflow-y:auto;
    scrollbar-width:none;
    display:block;
    min-height:24px;
}
textarea#messageInput::placeholder{color:var(--text-3)}
textarea#messageInput::-webkit-scrollbar{display:none}

.send-btn{
    width:40px;height:40px;
    border-radius:12px;border:none;
    background:var(--accent);
    color:#fff;font-size:17px;
    cursor:pointer;
    display:flex;align-items:center;justify-content:center;
    flex-shrink:0;
    transition:all .2s;
}
.send-btn:hover{background:var(--accent-light);transform:scale(1.06)}
.send-btn:active{transform:scale(.94)}
.send-btn:disabled{opacity:.4;cursor:not-allowed;transform:none}

.input-hint{
    font-size:11px;color:var(--text-3);
    text-align:center;margin-top:5px;
}

/* NON-CHAT PANELS */
.panel-header{
    padding:24px 24px 0;border-bottom:1px solid var(--border);padding-bottom:18px;
    flex-shrink:0;
}
.panel-header h2{font-family:'Space Grotesk',sans-serif;font-size:21px;font-weight:700;margin-bottom:5px}
.panel-header p{color:var(--text-2);font-size:13px}

.panel-content{flex:1;min-height:0;overflow-y:auto;padding:22px 24px}

/* Teach */
.teach-card{
    background:var(--bg-card);border:1px solid var(--border);
    border-radius:var(--r);padding:22px;max-width:560px;
}
.form-group{display:flex;flex-direction:column;gap:5px;position:relative}
.form-group label{font-size:12px;font-weight:600;color:var(--text-2);text-transform:uppercase;letter-spacing:.5px}
.form-group input,.form-group textarea{
    background:var(--bg-input);border:1.5px solid var(--border);
    border-radius:var(--r-sm);color:var(--text-1);
    font-family:'Be Vietnam Pro',sans-serif;font-size:15px;
    padding:10px 13px;outline:none;resize:none;
    transition:border-color .2s;
}
.form-group input:focus,.form-group textarea:focus{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-glow)}
.char-count{font-size:11px;color:var(--text-3);text-align:right}
.arrow-divider{text-align:center;font-size:20px;padding:10px 0;color:var(--accent)}
.teach-btn{
    width:100%;margin-top:6px;padding:11px;
    background:var(--accent);border:none;border-radius:var(--r-sm);
    color:#fff;font-family:'Space Grotesk',sans-serif;font-size:15px;font-weight:600;
    cursor:pointer;transition:all .2s;
}
.teach-btn:hover{background:var(--accent-light)}
.teach-result{margin-top:12px;padding:11px 15px;border-radius:var(--r-sm);font-size:14px;text-align:center;font-weight:500}
.teach-result.success{background:rgba(74,222,128,.1);border:1px solid rgba(74,222,128,.3);color:var(--green)}
.teach-result.error{background:rgba(248,113,113,.1);border:1px solid rgba(248,113,113,.3);color:var(--red)}
.teach-result.hidden{display:none}
.teach-tips{margin-top:22px;max-width:560px}
.teach-tips h3{font-size:14px;font-weight:600;margin-bottom:10px;color:var(--text-2)}
.teach-tips ul{list-style:none;display:flex;flex-direction:column;gap:7px}
.teach-tips li{font-size:13px;color:var(--text-2);padding:8px 12px;background:var(--bg-card);border-radius:var(--r-sm);border-left:3px solid var(--accent)}

/* About */
.about-hero{text-align:center;padding:16px 0 28px}
.about-avatar{font-size:60px;margin-bottom:10px;display:block;filter:drop-shadow(0 0 18px rgba(167,139,250,.5))}
.about-hero h1{font-family:'Space Grotesk',sans-serif;font-size:26px;font-weight:700;margin-bottom:5px}
.about-hero p{color:var(--text-2)}
.about-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px;margin-bottom:24px}
.about-card{
    background:var(--bg-card);border:1px solid var(--border);
    border-radius:var(--r);padding:18px;text-align:center;transition:border-color .2s;
}
.about-card:hover{border-color:var(--border-hi)}
.about-icon{font-size:30px;display:block;margin-bottom:8px}
.about-card h3{font-family:'Space Grotesk',sans-serif;font-size:14px;font-weight:600;margin-bottom:5px}
.about-card p{font-size:12px;color:var(--text-2);line-height:1.5}
.about-tech{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--r);padding:18px}
.about-tech h3{font-size:14px;font-weight:600;margin-bottom:12px;color:var(--text-2)}
.tech-tags{display:flex;flex-wrap:wrap;gap:7px}
.tech-tag{
    padding:4px 13px;background:var(--accent-glow);
    border:1px solid rgba(139,92,246,.3);border-radius:var(--r-pill);
    font-size:12px;color:var(--accent-light);font-weight:500;
}

/* TOAST */
.toast{
    position:fixed;bottom:22px;left:50%;
    transform:translateX(-50%) translateY(80px);
    background:var(--bg-card);border:1px solid var(--border);
    color:var(--text-1);padding:11px 20px;
    border-radius:var(--r-pill);font-size:14px;font-weight:500;
    box-shadow:0 4px 20px rgba(0,0,0,.4);
    transition:transform .35s cubic-bezier(.34,1.56,.64,1);
    pointer-events:none;z-index:200;white-space:nowrap;
}
.toast.show{transform:translateX(-50%) translateY(0)}

/* RESPONSIVE */
@media(max-width:680px){
    .sidebar{
        position:fixed;left:0;top:0;bottom:0;z-index:100;
        transform:translateX(-100%);
        box-shadow:none;
    }
    .sidebar.open{
        transform:translateX(0);
        box-shadow:4px 0 24px rgba(0,0,0,.5);
    }
    .menu-toggle{display:flex}
    .about-grid{grid-template-columns:1fr}
    .chat-messages{padding:14px 12px}
    .msg-content{max-width:80%}
    .panel-content{padding:16px}
    .panel-header{padding:16px}
    .sidebar-overlay{
        display:block;
        position:fixed;inset:0;
        background:rgba(0,0,0,.5);
        z-index:99;
    }
}
/* Nút quay lại/đóng panel */
.back-btn {
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-2);
    padding: 6px 12px;
    border-radius: var(--r-sm);
    font-size: 13px;
    cursor: pointer;
    margin-bottom: 10px;
    display: inline-flex;
    align-items: center;
    transition: all 0.2s;
}

.back-btn:hover {
    background: var(--accent-glow);
    color: var(--text-1);
    border-color: var(--accent);
}

/* Chỉ hiển thị nút quay lại trên mobile nếu cần thiết, 
   hoặc để luôn hiển thị để người dùng dễ thao tác */
@media(min-width:681px) {
    .back-btn { display: none; } /* Trên máy tính có sidebar rồi nên ẩn nút này đi */
}

/* ═══════════════════════════════════════════════
   PI NETWORK - Hồ sơ tài khoản / XP / Danh hiệu
   ═══════════════════════════════════════════════ */
.hidden{display:none !important}

.pi-profile-card{
    padding:12px 14px;
    border-bottom:1px solid var(--border);
    flex-shrink:0;
}

.pi-login-btn{
    width:100%;
    display:flex;align-items:center;justify-content:center;gap:8px;
    padding:10px 12px;
    background:linear-gradient(135deg,#7c3aed,#a78bfa);
    border:none;border-radius:var(--r-sm);
    color:#fff;font-family:'Space Grotesk',sans-serif;font-weight:600;font-size:13.5px;
    cursor:pointer;transition:all .2s;
    box-shadow:0 2px 14px rgba(124,58,237,.35);
}
.pi-login-btn:hover{filter:brightness(1.1);transform:translateY(-1px)}
.pi-login-btn:disabled{opacity:.6;cursor:wait}
.pi-logo{
    font-weight:700;font-size:15px;
    width:20px;height:20px;border-radius:50%;
    background:rgba(255,255,255,.25);
    display:inline-flex;align-items:center;justify-content:center;
}

.pi-profile{display:flex;align-items:center;gap:10px;margin-bottom:10px}
.pi-avatar{
    width:38px;height:38px;border-radius:50%;flex-shrink:0;
    background:linear-gradient(135deg,#7c3aed,#a78bfa);
    color:#fff;font-weight:700;font-size:13px;
    display:flex;align-items:center;justify-content:center;
    font-family:'Space Grotesk',sans-serif;
}
.pi-info{display:flex;flex-direction:column;min-width:0;flex:1}
.pi-username{font-weight:600;font-size:13.5px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.pi-title{font-size:11.5px;color:var(--accent-light)}
.pi-logout-btn{
    background:transparent;border:1px solid var(--border);color:var(--text-2);
    width:28px;height:28px;border-radius:8px;cursor:pointer;font-size:13px;
    flex-shrink:0;transition:.2s;
}
.pi-logout-btn:hover{border-color:var(--red);color:var(--red)}

.pi-level-row{display:flex;align-items:center;gap:7px;font-size:11px;color:var(--text-2)}
.xp-bar{
    flex:1;height:6px;border-radius:var(--r-pill);
    background:var(--bg-input);overflow:hidden;
}
.xp-fill{
    height:100%;border-radius:var(--r-pill);
    background:linear-gradient(90deg,#7c3aed,#a78bfa);
    transition:width .4s ease;
}
.xp-text{white-space:nowrap;font-size:10.5px;color:var(--text-3)}

/* Teach gate (chưa đăng nhập Pi) */
.teach-gate-card{
    background:var(--bg-card);border:1px solid var(--border);
    border-radius:var(--r);padding:30px 24px;max-width:420px;
    text-align:center;margin:20px auto;
}
.teach-gate-icon{font-size:38px;display:block;margin-bottom:10px}
.teach-gate-card h3{font-family:'Space Grotesk',sans-serif;font-size:16px;margin-bottom:8px}
.teach-gate-card p{font-size:13px;color:var(--text-2);margin-bottom:18px;line-height:1.5}
.teach-gate-card .pi-login-btn{max-width:240px;margin:0 auto}

.teach-quota-note{
    font-size:12.5px;color:var(--accent-light);
    background:var(--accent-glow);border:1px solid rgba(139,92,246,.3);
    border-radius:var(--r-sm);padding:9px 13px;margin-bottom:14px;max-width:560px;
}