:root {
    --sidebar-bg: rgba(255,255,255,0.78);
    --sidebar-hover: rgba(0,0,0,0.045);
    --sidebar-text: #1c1c1e;
    --sidebar-muted: #8e8e93;
    --main-bg: #f2f2f7;
    --msg-user-bg: #007aff;
    --text: #1c1c1e;
    --text-dim: #6e6e73;
    --primary: #007aff;
    --primary-hover: #0062cc;
    --danger: #ff3b30;
    --border: rgba(0,0,0,0.08);
    --border-subtle: rgba(0,0,0,0.05);
    --glass-bg: rgba(255,255,255,0.7);
    --glass-border: rgba(255,255,255,0.85);
    --glass-strong: rgba(255,255,255,0.92);
    --radius: 14px;
    --radius-lg: 20px;
    --radius-xl: 26px;
    --shadow-sm: 0 1px 4px rgba(0,0,0,0.07);
    --shadow-md: 0 4px 20px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
    --tf: 0.15s cubic-bezier(0.4,0,0.2,1);
    --tn: 0.25s cubic-bezier(0.4,0,0.2,1);
    --ts: 0.35s cubic-bezier(0.4,0,0.2,1);
}

*{box-sizing:border-box;margin:0;padding:0;}
html{-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;}

body{
    min-height:100vh;
    font-family:-apple-system,BlinkMacSystemFont,"SF Pro Text","Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
    color:var(--text);
    background:var(--main-bg);
    display:flex;
    overflow:hidden;
    letter-spacing:-0.01em;
}

body::before{
    content:'';
    position:fixed;inset:0;z-index:0;pointer-events:none;
    background:
        radial-gradient(ellipse 70% 55% at 15% 8%, rgba(0,122,255,0.06) 0%, transparent 60%),
        radial-gradient(ellipse 55% 45% at 85% 85%, rgba(88,86,214,0.05) 0%, transparent 60%),
        radial-gradient(ellipse 45% 35% at 55% 35%, rgba(52,199,89,0.03) 0%, transparent 50%);
}

/* ════════════════════════════════
   SIDEBAR
════════════════════════════════ */
.sidebar{
    width:260px;
    min-height:100vh;
    background:var(--sidebar-bg);
    backdrop-filter:blur(28px) saturate(200%);
    -webkit-backdrop-filter:blur(28px) saturate(200%);
    display:flex;flex-direction:column;
    position:fixed;left:0;top:0;bottom:0;z-index:100;
    border-right:1px solid rgba(0,0,0,0.06);
    box-shadow:0 0 0 0.5px rgba(0,0,0,0.04), 2px 0 24px rgba(0,0,0,0.06);
}

.sidebar-header{
    padding:20px 14px 10px;
    display:flex;flex-direction:column;gap:8px;
}

/* App title row */
.sidebar-title{
    display:flex;align-items:center;gap:10px;
    padding:0 4px 8px;
    border-bottom:1px solid var(--border-subtle);
}
.sidebar-title-icon{
    width:30px;height:30px;border-radius:8px;
    overflow:hidden;flex-shrink:0;
}
.sidebar-title-icon img{width:100%;height:100%;object-fit:cover;display:block;}
.sidebar-title-text{
    font-size:15px;font-weight:700;color:var(--sidebar-text);
    letter-spacing:-0.02em;
}

.btn-new{
    width:100%;
    display:flex;align-items:center;gap:9px;
    padding:10px 14px;
    border:1px solid rgba(0,122,255,0.18);
    border-radius:12px;
    background:rgba(0,122,255,0.07);
    color:var(--primary);
    font:inherit;font-size:13.5px;font-weight:600;
    cursor:pointer;
    transition:all var(--tf);
}
.btn-new:hover{
    background:rgba(0,122,255,0.13);
    border-color:rgba(0,122,255,0.3);
    box-shadow:0 2px 10px rgba(0,122,255,0.1);
    transform:translateY(-1px);
}
.btn-new svg{opacity:0.75;flex-shrink:0;transition:opacity var(--tf);}
.btn-new:hover svg{opacity:1;}

/* History */
.sidebar-history{flex:1;overflow-y:auto;padding:4px 10px;}

.history-label{
    font-size:10px;font-weight:700;
    color:var(--sidebar-muted);
    text-transform:uppercase;letter-spacing:0.08em;
    padding:10px 6px 6px;
}

.history-list{display:flex;flex-direction:column;gap:1px;}

.history-item{
    display:flex;align-items:center;gap:10px;
    padding:8px 10px;
    border-radius:10px;
    color:var(--sidebar-text);
    text-decoration:none;
    font-size:13px;
    transition:all var(--tf);
    position:relative;
    overflow:hidden;
}
.history-item:hover{background:var(--sidebar-hover);}
.history-item.is-active{background:rgba(0,122,255,0.08);}

/* Thumbnail */
.history-thumb{
    width:32px;height:32px;border-radius:7px;
    background:linear-gradient(135deg,rgba(0,122,255,0.12),rgba(88,86,214,0.1));
    display:flex;align-items:center;justify-content:center;
    flex-shrink:0;overflow:hidden;
    border:1px solid rgba(0,0,0,0.06);
}
.history-thumb img{width:100%;height:100%;object-fit:cover;border-radius:6px;}
.history-thumb svg{color:var(--sidebar-muted);opacity:0.6;}
.history-item.is-active .history-thumb{background:rgba(0,122,255,0.12);}
.history-item.is-active .history-thumb svg{color:var(--primary);opacity:0.8;}

.history-info{flex:1;min-width:0;}
.history-info-text{
    font-size:12.5px;font-weight:500;
    color:var(--sidebar-text);
    white-space:nowrap;overflow:hidden;text-overflow:ellipsis;
    line-height:1.3;
}
.history-info-meta{
    font-size:10.5px;color:var(--sidebar-muted);
    margin-top:1px;
    white-space:nowrap;overflow:hidden;text-overflow:ellipsis;
}
.history-item.is-active .history-info-text{color:var(--primary);}

/* Processing dot */
.history-dot{
    width:6px;height:6px;border-radius:50%;
    background:var(--primary);flex-shrink:0;
    animation:dotPulse 1.5s infinite;
}
@keyframes dotPulse{
    0%,100%{opacity:0.4;transform:scale(0.8);}
    50%{opacity:1;transform:scale(1);}
}

.sidebar-footer{
    padding:12px 14px 16px;
    border-top:1px solid var(--border);
}
.user-badge{
    display:flex;align-items:center;gap:10px;
    padding:8px 10px;border-radius:10px;
    transition:background var(--tf);cursor:default;
}
.user-badge:hover{background:var(--sidebar-hover);}
.user-avatar{
    width:30px;height:30px;border-radius:9px;
    overflow:hidden;flex-shrink:0;
}
.user-avatar img{width:100%;height:100%;object-fit:cover;display:block;}
.user-name{font-size:13px;font-weight:600;color:var(--sidebar-text);}

/* ════════════════════════════════
   MAIN WRAP
════════════════════════════════ */
.main-wrap{
    flex:1;margin-left:260px;height:100vh;
    display:flex;flex-direction:column;
    position:relative;z-index:1;
}

.mobile-toggle{
    display:none;position:absolute;top:12px;left:12px;z-index:50;
    width:38px;height:38px;border:1px solid var(--border);border-radius:10px;
    background:var(--glass-bg);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
    color:var(--text);cursor:pointer;
    align-items:center;justify-content:center;
    transition:all var(--tf);box-shadow:var(--shadow-sm);
}
.mobile-toggle:hover{background:rgba(255,255,255,0.9);}

/* ════════════════════════════════
   CHAT MESSAGES
════════════════════════════════ */
.chat-main{flex:1;overflow-y:auto;scroll-behavior:smooth;}

.chat-messages{
    max-width:760px;margin:0 auto;
    padding:32px 28px 150px;
}

/* ── Message row ── */
.msg{
    display:flex;gap:12px;
    padding:14px 0;
    animation:msgIn 0.3s ease-out;
}
@keyframes msgIn{
    from{opacity:0;transform:translateY(5px);}
    to{opacity:1;transform:translateY(0);}
}

.msg-avatar{
    width:32px;height:32px;border-radius:50%;
    display:flex;align-items:center;justify-content:center;
    font-size:11px;font-weight:700;flex-shrink:0;
    box-shadow:var(--shadow-sm);
    margin-top:2px;
}
.user-av{background:linear-gradient(135deg,#007aff,#5856d6);color:#fff;}
.ai-av{background:transparent;overflow:hidden;}
.ai-av img{width:100%;height:100%;object-fit:cover;display:block;border-radius:50%;}

/* User — right aligned */
.msg-user{flex-direction:row-reverse;}
.msg-user .msg-body{
    display:flex;flex-direction:column;align-items:flex-end;
    /* no flex:1 — shrink to content */
    max-width:72%;
}
.msg-bubble{
    background:var(--msg-user-bg);color:#fff;
    border-radius:18px 18px 4px 18px;
    padding:10px 15px;
    font-size:14.5px;line-height:1.65;
    word-break:break-word;
    box-shadow:0 2px 10px rgba(0,122,255,0.18);
}

/* AI — left, card style, width fits content */
.msg-assistant{align-items:flex-start;}
.msg-assistant .msg-body{
    /* KEY FIX: don't stretch to full width */
    display:inline-flex;
    flex-direction:column;
    max-width:82%;
    background:var(--glass-strong);
    backdrop-filter:blur(20px) saturate(160%);
    -webkit-backdrop-filter:blur(20px) saturate(160%);
    border:1px solid var(--glass-border);
    border-radius:4px 18px 18px 18px;
    padding:12px 16px;
    box-shadow:var(--shadow-md);
}

.msg-text{font-size:14.5px;line-height:1.7;color:var(--text);}

.msg-images{
    display:flex;flex-wrap:wrap;gap:10px;
    margin-top:10px;
}
.msg-images a{
    display:block;border-radius:12px;overflow:hidden;
    cursor:zoom-in;transition:all var(--tn);
    max-width:280px;
    box-shadow:var(--shadow-md);border:1px solid var(--border);
}
.msg-images a:hover{
    transform:translateY(-3px) scale(1.01);
    box-shadow:var(--shadow-lg);
    border-color:rgba(0,122,255,0.2);
}
.msg-images img{width:100%;display:block;}

.msg-meta{
    font-size:10.5px;color:var(--text-dim);
    margin-top:8px;font-weight:500;opacity:0.6;
    letter-spacing:0.02em;
}

.msg-loading{
    display:flex;align-items:center;gap:8px;
    font-size:13px;color:var(--text-dim);font-weight:500;
    padding:2px 0;
}

.msg-failed{
    display:flex;align-items:center;gap:10px;
    padding:2px 0;
}
.msg-failed span{font-size:13px;color:var(--danger);font-weight:500;}
.btn-retry{
    display:inline-flex;align-items:center;gap:5px;
    padding:5px 12px;
    border:1px solid rgba(0,122,255,0.2);
    border-radius:20px;
    background:rgba(0,122,255,0.06);
    color:var(--primary);
    font:inherit;font-size:12px;font-weight:600;
    cursor:pointer;
    transition:all var(--tf);
    flex-shrink:0;
}
.btn-retry:hover{background:rgba(0,122,255,0.12);border-color:rgba(0,122,255,0.35);transform:scale(1.03);}
.btn-retry svg{flex-shrink:0;}

/* Dots */
.dot-flashing{display:flex;align-items:center;gap:4px;}
.dot-flashing::before,.dot-flashing::after{
    content:'';display:block;
    width:5px;height:5px;border-radius:50%;
    background:var(--primary);
    animation:dotB 1.4s infinite ease-in-out both;
}
.dot-flashing::before{animation-delay:-0.32s;}
.dot-flashing::after{animation-delay:0s;}
.dot-flashing span{
    display:block;width:5px;height:5px;border-radius:50%;
    background:var(--primary);
    animation:dotB 1.4s infinite ease-in-out both;
    animation-delay:-0.16s;
}
@keyframes dotB{
    0%,80%,100%{opacity:0.2;transform:scale(0.7);}
    40%{opacity:1;transform:scale(1);}
}

/* ════════════════════════════════
   WELCOME
════════════════════════════════ */
.welcome{
    display:flex;flex-direction:column;align-items:center;
    text-align:center;padding:80px 24px 60px;
    max-width:640px;margin:0 auto;
    animation:wFade 0.5s ease-out;
}
@keyframes wFade{from{opacity:0;transform:translateY(10px);}to{opacity:1;transform:translateY(0);}}

.welcome-icon{
    width:72px;height:72px;border-radius:20px;
    background:linear-gradient(135deg,rgba(0,122,255,0.1),rgba(88,86,214,0.08));
    display:flex;align-items:center;justify-content:center;
    margin-bottom:20px;color:var(--primary);
    box-shadow:0 4px 20px rgba(0,122,255,0.1),inset 0 1px 0 rgba(255,255,255,0.8);
    border:1px solid rgba(0,122,255,0.1);
}
.welcome h1{font-size:30px;font-weight:700;margin-bottom:8px;color:var(--text);letter-spacing:-0.03em;}
.welcome p{font-size:15px;color:var(--text-dim);margin-bottom:36px;line-height:1.6;}

.welcome-tips{display:grid;grid-template-columns:1fr 1fr;gap:10px;width:100%;}

.tip-card{
    display:flex;align-items:center;gap:10px;
    padding:13px 15px;
    border:1px solid var(--glass-border);border-radius:var(--radius);
    background:var(--glass-bg);
    backdrop-filter:blur(16px) saturate(160%);-webkit-backdrop-filter:blur(16px) saturate(160%);
    color:var(--text);font:inherit;font-size:13px;font-weight:500;
    cursor:pointer;text-align:left;
    transition:all var(--tn);box-shadow:var(--shadow-sm);
}
.tip-card:hover{
    border-color:rgba(0,122,255,0.22);background:rgba(255,255,255,0.88);
    box-shadow:var(--shadow-md);transform:translateY(-2px);
}
.tip-card svg{flex-shrink:0;color:var(--primary);opacity:0.75;transition:opacity var(--tf);}
.tip-card:hover svg{opacity:1;}

/* ════════════════════════════════
   INPUT BAR  — iOS style
════════════════════════════════ */
.chat-input-bar{
    position:sticky;bottom:0;
    padding:0 28px 22px;
    background:linear-gradient(to top, var(--main-bg) 60%, transparent);
}

.input-wrap{
    max-width:760px;margin:0 auto;
    background:var(--glass-strong);
    backdrop-filter:blur(28px) saturate(200%);
    -webkit-backdrop-filter:blur(28px) saturate(200%);
    border:1px solid var(--glass-border);
    border-radius:var(--radius-xl);
    transition:all var(--tn);
    box-shadow:var(--shadow-md), inset 0 1px 0 rgba(255,255,255,0.95);
}
.input-wrap:focus-within{
    border-color:rgba(0,122,255,0.28);
    box-shadow:var(--shadow-md), 0 0 0 3.5px rgba(0,122,255,0.07), inset 0 1px 0 rgba(255,255,255,0.95);
}

/* Textarea row */
.input-row{
    display:flex;align-items:flex-end;
    padding:14px 12px 10px 12px;gap:8px;
}

/* Attach button */
.btn-attach{
    width:32px;height:32px;border:none;border-radius:9px;
    background:rgba(0,0,0,0.04);
    color:var(--text-dim);
    cursor:pointer;display:flex;align-items:center;justify-content:center;
    flex-shrink:0;transition:all var(--tf);
    margin-bottom:1px;
}
.btn-attach:hover{background:rgba(0,122,255,0.08);color:var(--primary);}

/* Ref image previews inside input */
.ref-previews{
    display:none;
    flex-wrap:wrap;gap:8px;
    padding:10px 16px 0;
}
.ref-thumb{
    position:relative;width:56px;height:56px;border-radius:10px;
    overflow:visible;flex-shrink:0;
}
.ref-thumb img{
    width:56px;height:56px;object-fit:cover;
    border-radius:10px;border:1px solid var(--border);
    display:block;
}
.ref-thumb-del{
    position:absolute;top:-6px;right:-6px;
    width:18px;height:18px;border-radius:50%;
    background:#1c1c1e;color:#fff;border:none;
    display:flex;align-items:center;justify-content:center;
    cursor:pointer;padding:0;
    box-shadow:0 1px 4px rgba(0,0,0,0.2);
    transition:transform var(--tf);
}
.ref-thumb-del:hover{transform:scale(1.15);}

/* Ref images in user bubble */
.msg-refs{
    display:flex;flex-wrap:wrap;gap:6px;
    margin-bottom:6px;
    justify-content:flex-end;
}
.msg-refs img{
    width:52px;height:52px;object-fit:cover;
    border-radius:8px;border:1px solid rgba(255,255,255,0.3);
}
.input-row textarea{
    flex:1;border:none;background:transparent;
    color:var(--text);font:inherit;font-size:15px;line-height:1.5;
    resize:none;outline:none;max-height:200px;padding:4px 0;
}
.input-row textarea::placeholder{color:var(--text-dim);opacity:0.65;}

.btn-send{
    width:34px;height:34px;border:none;border-radius:10px;
    background:var(--primary);color:#fff;
    cursor:pointer;display:flex;align-items:center;justify-content:center;
    flex-shrink:0;transition:all var(--tf);
    box-shadow:0 2px 8px rgba(0,122,255,0.28);
}
.btn-send:hover{background:var(--primary-hover);transform:scale(1.07);box-shadow:0 4px 14px rgba(0,122,255,0.38);}
.btn-send.loading,.btn-send:disabled{opacity:0.4;pointer-events:none;transform:none;box-shadow:none;}

/* Options row */
.input-options{
    display:flex;align-items:center;gap:6px;
    padding:0 16px 12px;
    flex-wrap:wrap;
}

/* Divider */
.input-divider{
    height:1px;background:rgba(0,0,0,0.05);margin:0 16px;
}

/* ── Custom picker ── */
.opt-picker{position:relative;}

.opt-pill{
    display:inline-flex;align-items:center;gap:5px;
    padding:5px 10px 5px 9px;
    border:1px solid rgba(0,0,0,0.09);
    border-radius:20px;
    background:rgba(0,0,0,0.03);
    color:var(--text-dim);
    font:inherit;font-size:12px;font-weight:500;
    cursor:pointer;
    transition:all var(--tf);
    white-space:nowrap;
    user-select:none;
}
.opt-pill:hover{
    border-color:rgba(0,0,0,0.16);
    background:rgba(0,0,0,0.055);
    color:var(--text);
}
.opt-picker.is-open .opt-pill{
    border-color:rgba(0,122,255,0.35);
    background:rgba(0,122,255,0.06);
    color:var(--primary);
    box-shadow:0 0 0 2.5px rgba(0,122,255,0.08);
}
.opt-pill svg:first-child{opacity:0.6;flex-shrink:0;}
.opt-pill-label{color:var(--text);font-weight:600;}
.opt-pill-arrow{
    opacity:0.45;flex-shrink:0;
    transition:transform var(--tf);
}
.opt-picker.is-open .opt-pill-arrow{transform:rotate(180deg);opacity:0.7;}

/* Dropdown panel */
.opt-dropdown{
    position:absolute;
    bottom:calc(100% + 8px);
    left:0;
    min-width:140px;
    background:rgba(255,255,255,0.96);
    backdrop-filter:blur(20px) saturate(180%);
    -webkit-backdrop-filter:blur(20px) saturate(180%);
    border:1px solid rgba(0,0,0,0.08);
    border-radius:14px;
    box-shadow:0 8px 32px rgba(0,0,0,0.12), 0 2px 8px rgba(0,0,0,0.06);
    padding:6px;
    z-index:200;
    opacity:0;pointer-events:none;
    transform:translateY(6px) scale(0.97);
    transform-origin:bottom left;
    transition:opacity var(--tf), transform var(--tf);
}
.opt-picker.is-open .opt-dropdown{
    opacity:1;pointer-events:auto;
    transform:translateY(0) scale(1);
}

/* Ratio dropdown — wider, 2-col grid */
.opt-dropdown-ratio{
    min-width:200px;
    display:grid;
    grid-template-columns:1fr 1fr;
    gap:2px;
}

.opt-item{
    display:flex;align-items:center;gap:8px;
    width:100%;padding:8px 10px;
    border:none;border-radius:9px;
    background:transparent;
    color:var(--text);
    font:inherit;font-size:13px;font-weight:500;
    cursor:pointer;text-align:left;
    transition:background var(--tf);
    white-space:nowrap;
}
.opt-item:hover{background:rgba(0,0,0,0.05);}
.opt-item.is-selected{color:var(--primary);background:rgba(0,122,255,0.07);}
.opt-item-check{
    flex-shrink:0;opacity:0;
    color:var(--primary);
    transition:opacity var(--tf);
}
.opt-item.is-selected .opt-item-check{opacity:1;}

.input-hint{
    max-width:760px;margin:7px auto 0;
    text-align:center;font-size:11px;
    color:var(--text-dim);opacity:0.5;
}

/* ════════════════════════════════
   LIGHTBOX
════════════════════════════════ */
.lightbox{
    position:fixed;inset:0;z-index:10000;
    background:rgba(0,0,0,0.55);
    backdrop-filter:blur(28px) saturate(120%);-webkit-backdrop-filter:blur(28px) saturate(120%);
    display:flex;align-items:center;justify-content:center;
    opacity:0;pointer-events:none;transition:opacity var(--tn);
}
.lightbox.open{opacity:1;pointer-events:auto;}
.lightbox img{
    max-width:90vw;max-height:90vh;
    border-radius:16px;
    box-shadow:0 24px 80px rgba(0,0,0,0.28);
}
.lightbox.open img{animation:lbIn 0.28s cubic-bezier(0.34,1.56,0.64,1);}
@keyframes lbIn{from{transform:scale(0.88);opacity:0;}to{transform:scale(1);opacity:1;}}

.lb-close{
    position:absolute;top:20px;right:20px;
    background:rgba(255,255,255,0.14);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
    border:1px solid rgba(255,255,255,0.22);border-radius:50%;
    width:42px;height:42px;display:flex;align-items:center;justify-content:center;
    cursor:pointer;color:#fff;transition:all var(--tf);
}
.lb-close:hover{background:rgba(255,255,255,0.24);transform:scale(1.08);}

/* ════════════════════════════════
   SCROLLBAR
════════════════════════════════ */
::-webkit-scrollbar{width:4px;}
::-webkit-scrollbar-track{background:transparent;}
::-webkit-scrollbar-thumb{background:rgba(0,0,0,0.1);border-radius:4px;}
::-webkit-scrollbar-thumb:hover{background:rgba(0,0,0,0.18);}
::selection{background:rgba(0,122,255,0.18);}

/* ════════════════════════════════
   AUTH PAGES
════════════════════════════════ */
.auth-body{
    min-height:100vh;display:flex;align-items:center;justify-content:center;
    background:var(--main-bg);
    padding:20px;
}
.auth-body::before{
    content:'';position:fixed;inset:0;z-index:0;pointer-events:none;
    background:
        radial-gradient(ellipse 70% 55% at 15% 8%, rgba(0,122,255,0.06) 0%, transparent 60%),
        radial-gradient(ellipse 55% 45% at 85% 85%, rgba(88,86,214,0.05) 0%, transparent 60%);
}
.auth-card{
    position:relative;z-index:1;
    width:100%;max-width:400px;
    background:var(--glass-strong);
    backdrop-filter:blur(28px) saturate(200%);
    -webkit-backdrop-filter:blur(28px) saturate(200%);
    border:1px solid var(--glass-border);
    border-radius:24px;
    padding:40px 36px;
    box-shadow:var(--shadow-lg), inset 0 1px 0 rgba(255,255,255,0.95);
    text-align:center;
}
.auth-logo{
    width:64px;height:64px;border-radius:18px;
    overflow:hidden;margin:0 auto 16px;
    box-shadow:var(--shadow-md);
}
.auth-logo img{width:100%;height:100%;object-fit:cover;display:block;}
.auth-title{font-size:22px;font-weight:700;color:var(--text);letter-spacing:-0.02em;margin-bottom:4px;}
.auth-sub{font-size:14px;color:var(--text-dim);margin-bottom:24px;}
.auth-error{
    background:rgba(255,59,48,0.08);border:1px solid rgba(255,59,48,0.2);
    color:var(--danger);border-radius:10px;
    padding:10px 14px;font-size:13px;font-weight:500;
    margin-bottom:16px;text-align:left;
}
.auth-form{display:flex;flex-direction:column;gap:14px;text-align:left;}
.auth-field{display:flex;flex-direction:column;gap:5px;}
.auth-field label{font-size:12.5px;font-weight:600;color:var(--text-dim);display:flex;align-items:center;gap:6px;}
.auth-hint{font-weight:400;opacity:0.7;}
.auth-field input{
    border:1px solid rgba(0,0,0,0.1);border-radius:12px;
    padding:11px 14px;font:inherit;font-size:14.5px;
    background:rgba(0,0,0,0.03);color:var(--text);outline:none;
    transition:all var(--tf);
}
.auth-field input:focus{border-color:var(--primary);box-shadow:0 0 0 3px rgba(0,122,255,0.08);background:#fff;}
.auth-field input::placeholder{color:var(--text-dim);opacity:0.6;}
.auth-btn{
    margin-top:4px;padding:12px;border:none;border-radius:12px;
    background:var(--primary);color:#fff;
    font:inherit;font-size:15px;font-weight:600;
    cursor:pointer;transition:all var(--tf);
    box-shadow:0 2px 10px rgba(0,122,255,0.3);
}
.auth-btn:hover{background:var(--primary-hover);transform:translateY(-1px);box-shadow:0 4px 16px rgba(0,122,255,0.4);}
.auth-switch{margin-top:20px;font-size:13px;color:var(--text-dim);}
.auth-switch a{color:var(--primary);font-weight:600;text-decoration:none;}
.auth-switch a:hover{text-decoration:underline;}

/* Logout button */
.btn-logout{
    width:100%;display:flex;align-items:center;justify-content:center;gap:7px;
    padding:8px 12px;border:1px solid rgba(0,0,0,0.08);border-radius:10px;
    background:transparent;color:var(--text-dim);
    font:inherit;font-size:12.5px;font-weight:500;cursor:pointer;
    transition:all var(--tf);
}
.btn-logout:hover{background:rgba(255,59,48,0.06);border-color:rgba(255,59,48,0.2);color:var(--danger);}

/* Lightbox download button */
.lb-download{
    position:absolute;bottom:28px;left:50%;transform:translateX(-50%);
    display:inline-flex;align-items:center;gap:8px;
    padding:10px 22px;
    background:rgba(255,255,255,0.18);
    backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
    border:1px solid rgba(255,255,255,0.3);
    border-radius:24px;color:#fff;
    font:inherit;font-size:14px;font-weight:600;
    cursor:pointer;transition:all var(--tf);
    white-space:nowrap;
}
.lb-download:hover{background:rgba(255,255,255,0.28);transform:translateX(-50%) translateY(-2px);}

/* ════════════════════════════════
   MOBILE
════════════════════════════════ */
@media(max-width:768px){
    .sidebar{transform:translateX(-100%);transition:transform var(--ts);}
    .sidebar.open{transform:translateX(0);box-shadow:20px 0 60px rgba(0,0,0,0.12);}
    .mobile-toggle{display:flex;}
    .mobile-toggle .icon-close{display:none;}
    .mobile-toggle.is-open .icon-menu{display:none;}
    .mobile-toggle.is-open .icon-close{display:block;}
    .sidebar-overlay{
        display:none;
        position:fixed;inset:0;z-index:99;
        background:rgba(0,0,0,0.25);
        backdrop-filter:blur(2px);
        -webkit-backdrop-filter:blur(2px);
        transition:opacity var(--ts);
    }
    .sidebar-overlay.active{display:block;}
    .main-wrap{margin-left:0;}
    .chat-messages{padding:20px 14px 130px;}
    .chat-input-bar{padding:0 10px 14px;}
    .welcome{padding:56px 14px 40px;}
    .welcome h1{font-size:24px;}
    .welcome-tips{grid-template-columns:1fr;}
    .msg-images a{max-width:200px;}
    .input-row{padding:12px 10px 8px 14px;}
    .input-options{padding:0 12px 10px;}
    .msg-user .msg-body,.msg-assistant .msg-body{max-width:90%;}
}