/* ================================
   LAYOUT — Sidebar, Main, Header, Footer
   ================================ */

/* Mobile Header Logo */
.mobile-header-logo {
    height: 32px;
    width: auto;
    object-fit: contain;
}

[data-theme="dark"] .mobile-header-logo {
    filter: brightness(0) invert(1);
}

/* Sidebar Logo */
.sidebar-logo-container {
    display: block;
    text-align: center;
    padding: 8px 0 16px;
    text-decoration: none;
    border: none;
    outline: none;
}

.sidebar-logo-img {
    width: 160px;
    height: auto;
    max-height: 52px;
    object-fit: contain;
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), filter 0.3s ease;
    filter: drop-shadow(0 1px 2px rgba(44, 51, 70, 0.06));
}

.sidebar-logo-img:hover {
    transform: scale(1.03);
}

[data-theme="dark"] .sidebar-logo-img {
    filter: brightness(0) invert(1) drop-shadow(0 1px 2px rgba(237, 238, 239, 0.08));
}

/* ================================
   SIDEBAR
   ================================ */
.sidebar {
    width: 260px;
    background: var(--sidebar-background);
    border-right: 1px solid var(--border-light);
    display: flex;
    flex-direction: column;
    height: calc(100vh - 24px);
    position: fixed;
    left: 12px;
    top: 12px;
    z-index: 100;
    padding: 20px 16px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-soft);
    transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.sidebar-header {
    margin-bottom: 20px;
}

.brand {
    font-family: 'DM Sans', sans-serif;
    font-size: 20px;
    font-weight: 400;
    color: var(--text-primary);
    margin-bottom: 20px;
    text-align: left;
    letter-spacing: -0.02em;
}

.new-chat-btn {
    width: 100%;
    background: var(--primary);
    color: var(--text-on-primary);
    border: none;
    border-radius: var(--radius-full);
    padding: 11px 20px;
    font-family: 'DM Sans', sans-serif;
    font-size: 13.5px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 2px 8px rgba(176, 78, 132, 0.2);
    letter-spacing: 0.01em;
}

.new-chat-btn:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(176, 78, 132, 0.3);
}

.new-chat-btn:focus-visible {
    outline: 3px solid var(--primary);
    outline-offset: 3px;
}

.sidebar-content {
    flex: 1;
    overflow-y: auto;
    margin: 0 -4px;
    padding: 0 4px;
}

.chats-section {
    margin-bottom: 16px;
}

.chats-title {
    font-size: 10.5px;
    font-weight: 700;
    color: var(--text-tertiary);
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding-left: 4px;
}

.chat-list {
    display: flex;
    flex-direction: column;
    gap: 3px;
}

.chat-item {
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 13.5px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    position: relative;
    border: 1px solid transparent;
    background: transparent;
}

.chat-item:hover {
    background: var(--surface-hover);
    border-color: var(--border-light);
}

.chat-item:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 1px;
}

.chat-item.active {
    background: var(--primary-light);
    border-color: rgba(176, 78, 132, 0.15);
    color: var(--primary);
    font-weight: 500;
}

.chat-item-content {
    display: flex;
    align-items: center;
    gap: 8px;
    flex: 1;
    min-width: 0;
}

.chat-item-processing {
    width: 14px;
    height: 14px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    flex-shrink: 0;
    opacity: 0.95;
}

.chat-item-processing i {
    font-size: 11px;
    line-height: 1;
}

.chat-item-text {
    flex: 1;
    min-width: 0;
}

.chat-item-title {
    font-size: 13px;
    font-weight: 450;
    color: var(--text-primary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    line-height: 1.5;
}

.chat-item-title-input {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-primary);
    border: 1.5px solid var(--primary);
    border-radius: 6px;
    padding: 4px 8px;
    width: 100%;
    background: var(--surface);
    outline: none;
    box-shadow: var(--shadow-glow);
    font-family: 'DM Sans', sans-serif;
}

.chat-item-actions {
    display: flex;
    gap: 2px;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.chat-item:hover .chat-item-actions {
    opacity: 1;
}

.chat-item-rename,
.chat-item-delete {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 4px 6px;
    border-radius: 6px;
    transition: all 0.15s ease;
    flex-shrink: 0;
    font-size: 11px;
}

.chat-item-rename:focus-visible,
.chat-item-delete:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 1px;
}

.chat-item-rename {
    color: var(--primary);
}

.chat-item-rename:hover {
    background: var(--primary-light);
}

.chat-item-delete {
    color: #C44A4A;
}

.chat-item-delete:hover {
    background: #FCEAEA;
}

[data-theme="dark"] .chat-item-delete:hover {
    background: #3d2a2a;
}

.chat-item-empty {
    text-align: center;
    padding: 32px 16px;
    color: var(--text-tertiary);
}

.chat-item-empty i {
    font-size: 28px;
    margin-bottom: 10px;
    opacity: 0.35;
    color: var(--text-tertiary);
}

.chat-item-empty p {
    font-size: 12.5px;
    margin-bottom: 3px;
}

.chat-item-empty-hint {
    font-size: 11px;
    opacity: 0.6;
}

.chat-item.search-chat {
    color: var(--text-secondary);
    font-style: italic;
}

/* Sidebar Footer */
.sidebar-footer {
    margin-top: auto;
    padding-top: 16px;
    border-top: 1px solid var(--border-light);
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.settings-btn {
    width: 100%;
    background: transparent;
    color: var(--text-primary);
    border: none;
    border-radius: var(--radius-sm);
    padding: 9px 12px;
    font-family: 'DM Sans', sans-serif;
    font-size: 13px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: all 0.2s ease;
    text-align: left;
}

.settings-btn:hover {
    background: var(--surface-hover);
}

.settings-btn:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Theme Toggle */
.theme-toggle {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
}

.theme-toggle-track {
    position: relative;
    width: 40px;
    height: 22px;
    flex-shrink: 0;
    background: var(--toggle-track);
    border-radius: var(--radius-full);
    transition: background 0.25s ease;
}

.theme-toggle:hover .theme-toggle-track {
    background: var(--toggle-track-hover);
}

.theme-toggle-thumb {
    position: absolute;
    left: 2px;
    top: 2px;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--toggle-thumb);
    box-shadow: 0 1px 3px var(--toggle-thumb-shadow);
    transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);
}

[data-theme="dark"] .theme-toggle-thumb {
    transform: translateX(18px);
}

.theme-toggle-label {
    font-size: 13px;
    color: var(--text-secondary);
    font-weight: 450;
}

/* ================================
   MAIN CONTENT
   ================================ */
.main-content {
    flex: 1;
    margin-left: 284px;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background: var(--background);
    position: relative;
    overflow-x: hidden;
}

/* Warm gradient wash behind main content */
.main-content::before {
    content: '';
    position: fixed;
    top: -30%;
    right: -20%;
    width: 70%;
    height: 70%;
    background: radial-gradient(ellipse at center, var(--primary-glow) 0%, transparent 70%);
    pointer-events: none;
    z-index: 0;
}

.main-header {
    position: absolute;
    top: 20px;
    left: 28px;
    right: 28px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    z-index: 10;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 10px;
}

.plan-badge {
    background: var(--surface);
    color: var(--text-secondary);
    padding: 5px 14px;
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 500;
    border: 1px solid var(--border);
    letter-spacing: 0.01em;
}

.query-counter-badge {
    background: var(--accent);
    color: var(--text-on-primary);
    padding: 5px 14px;
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 2px 6px rgba(44, 51, 70, 0.15);
    letter-spacing: 0.01em;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 10px;
}

.login-btn {
    color: var(--text-primary);
    font-family: 'DM Sans', sans-serif;
    font-size: 13px;
    font-weight: 550;
    text-decoration: none;
    padding: 7px 18px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-full);
    background: transparent;
    transition: all 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);
    letter-spacing: 0.01em;
}

.login-btn:hover {
    border-color: var(--primary);
    color: var(--primary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-soft);
}

.login-btn:focus-visible {
    outline: 3px solid var(--primary);
    outline-offset: 2px;
}

.signup-btn {
    background: var(--primary);
    color: var(--text-on-primary);
    font-family: 'DM Sans', sans-serif;
    font-size: 13px;
    font-weight: 600;
    text-decoration: none;
    padding: 7px 18px;
    border: 1.5px solid var(--primary);
    border-radius: var(--radius-full);
    transition: all 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);
    letter-spacing: 0.01em;
}

.signup-btn:hover {
    background: var(--primary-hover);
    border-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(176, 78, 132, 0.3);
}

.signup-btn:focus-visible {
    outline: 3px solid var(--primary-hover);
    outline-offset: 2px;
}

/* ================================
   CENTER CONTENT (Welcome)
   ================================ */
.center-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 100px 32px 32px;
    text-align: center;
    max-width: 1100px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.main-title {
    font-family: 'DM Sans', sans-serif;
    font-size: 52px;
    font-weight: 400;
    color: var(--text-primary);
    margin-bottom: 16px;
    line-height: 1.12;
    text-align: center;
    letter-spacing: -0.025em;
    animation: revealTitle 0.9s cubic-bezier(0.16, 1, 0.3, 1) 0.15s both;
}

.main-title-welcome {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0;
    margin-top: 0;
}

.main-subtitle {
    font-size: 17px;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.65;
    text-align: center;
    max-width: 900px;
    font-weight: 400;
    animation: revealSubtle 0.8s cubic-bezier(0.16, 1, 0.3, 1) 0.4s both;
}

/* Footer */
.main-footer {
    position: absolute;
    bottom: 20px;
    right: 28px;
    padding: 16px;
    border-top: none;
    pointer-events: none;
    z-index: 1;
}

.footer-text {
    font-size: 11.5px;
    color: var(--text-tertiary);
    margin: 0;
    letter-spacing: 0.02em;
    font-weight: 450;
}

/* Desktop/Mobile */
.desktop-only {
    display: block;
}

.mobile-header-branding {
    display: none;
}

.mobile-brand {
    font-family: 'DM Sans', sans-serif;
    font-size: 22px;
    font-weight: 400;
    color: var(--text-primary);
    text-align: center;
    margin: 0;
}