:root {
    --header-height: 72px;
    --sub-header-height: 72px;
    --sidebar-width: 280px;
    --list-width: 380px;
    --color-starlight: #00d4ff;
    --side-padding: 1.5rem;
}

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

/* ==========================================================================
   EMAIL APPLICATION LAYOUT
   ========================================================================== */

body.email-client { background-color: #08081a; color: #f1f5f9; margin: 0; }
html[data-theme="light"] body.email-client {
    background-color: #f8fafc;
    color: #1e293b;
}

.email-client {
    display: grid;
    grid-template-columns: var(--sidebar-width) 1fr;
    height: 100vh;
    overflow: hidden;
    width: 100%;
}

.email-main {
    display: grid;
    grid-template-columns: var(--list-width) 1fr;
    height: 100vh;
    overflow: hidden;
    width: 100%;
}

/* Sidebar */
email-sidebar {
    background: linear-gradient(
        180deg,
        rgba(8, 8, 26, 0.98) 0%,
        rgba(15, 23, 42, 0.98) 100%
    );
    border-right: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    flex-direction: column;
    height: 100vh;
}
html[data-theme="light"] email-sidebar {
    background: linear-gradient(180deg, #ffffff 0%, #f1f5f9 100%);
    border-right-color: #e2e8f0;
}

logo-section {
    height: var(--header-height);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0 var(--side-padding);
    flex-shrink: 0;
}
logo-section logo {
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 0.75rem;
    background: linear-gradient(135deg, #00d4ff 0%, #3b82f6 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}
logo-section brand {
    font-size: 1.25rem;
    font-weight: 700;
    background: linear-gradient(
        to right,
        var(--q-color-starlight-peach, #f59e0b),
        var(--q-color-starlight-blue, #00d4ff)
    );
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
html[data-theme="light"] logo-section brand {
    background: linear-gradient(135deg, #f59e0b 0%, #3b82f6 100%);
    -webkit-background-clip: text;
    background-clip: text;
}

compose-section {
    height: var(--sub-header-height);
    display: flex;
    align-items: center;
    padding: 0 var(--side-padding);
    flex-shrink: 0;
}
.compose-btn {
    background: linear-gradient(135deg, #00d4ff 0%, #3b82f6 100%);
    color: white !important;
    border: none;
    height: 3rem;
    width: 100%;
    border-radius: 0.75rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    box-shadow: 0 4px 15px rgba(0, 212, 255, 0.3);
}

sidebar-scrollable {
    flex: 1;
    overflow-y: auto;
    padding: 0 var(--side-padding);
}
email-sidebar nav {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin-bottom: 1.5rem;
}
email-sidebar nav button {
    display: flex !important;
    align-items: center !important;
    justify-content: flex-start !important;
    gap: 1rem;
    padding: 0.625rem 1rem;
    width: 100%;
    background: transparent !important;
    border: none;
    border-radius: 0.5rem;
    color: #94a3b8;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
}
email-sidebar nav button.active {
    background: rgba(0, 212, 255, 0.15) !important;
    color: #00d4ff;
}
html[data-theme="light"] email-sidebar nav button {
    color: #64748b;
}
html[data-theme="light"] email-sidebar nav button.active {
    background: rgba(59, 130, 246, 0.1) !important;
    color: #3b82f6;
}

email-sidebar .divider {
    height: 1px;
    background: rgba(255, 255, 255, 0.1);
    margin: 1rem 0;
}
html[data-theme="light"] email-sidebar .divider {
    background: #e2e8f0;
}

email-sidebar h3 {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: #64748b;
    margin-bottom: 1rem;
    padding-left: 1rem;
}
html[data-theme="light"] email-sidebar h3 {
    color: #0f172a;
}

email-sidebar .user-profile-section {
    padding: 1rem var(--side-padding);
    background: rgba(255, 255, 255, 0.03);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-top: auto;
}
html[data-theme="light"] email-sidebar .user-profile-section {
    background: #f8fafc;
    border-top-color: #e2e8f0;
}

/* ==========================================================================
   EMAIL APP COMPONENTS
   ========================================================================== */

/* Email List Pane */
email-list {
    border-right: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    flex-direction: column;
    height: 100vh;
    width: 100%;
}
html[data-theme="light"] email-list {
    background: #ffffff;
    border-right-color: #e2e8f0;
}

email-list .top-bar {
    height: var(--header-height);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 var(--side-padding);
    background: rgba(8, 8, 26, 0.5);
    flex-shrink: 0;
}
html[data-theme="light"] email-list .top-bar {
    background: #ffffff;
}

.search-container {
    height: var(--sub-header-height);
    display: flex;
    align-items: center;
    padding: 0 var(--side-padding);
    flex-shrink: 0;
}
html[data-theme="light"] .search-container:focus-within {
    box-shadow: none;
    border-color: transparent;
}

email-items {
    flex: 1;
    overflow-y: auto;
    width: 100%;
}

email-item {
    display: block;
    padding: 1rem var(--side-padding);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    cursor: pointer;
    width: 100%;
    transition: background 0.2s;
}
email-item:hover {
    background: rgba(255, 255, 255, 0.03);
}
email-item.active {
    background: rgba(0, 212, 255, 0.08);
    border-left: 3px solid #00d4ff;
}
html[data-theme="light"] email-item {
    border-bottom-color: #f1f5f9;
}
html[data-theme="light"] email-item:hover {
    background: #f8fafc;
}
html[data-theme="light"] email-item.active {
    background: rgba(59, 130, 246, 0.05);
}

email-meta {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.25rem;
    width: 100%;
}
email-sender {
    font-size: 0.875rem;
    color: #f1f5f9;
}
email-time {
    font-size: 0.75rem;
    color: #64748b;
}
email-subject {
    font-size: 0.875rem;
    color: #f1f5f9;
    margin-bottom: 0.25rem;
    display: block;
}
email-preview {
    font-size: 0.8125rem;
    color: #94a3b8;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    display: block;
}
html[data-theme="light"] email-sender,
html[data-theme="light"] email-subject {
    color: #0f172a;
}

email-labels {
    display: flex;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

/* Email Content Pane */
email-content {
    display: flex;
    flex-direction: column;
    height: 100vh;
}
html[data-theme="light"] email-content {
    background: #f8fafc;
}

content-top-bar {
    height: var(--header-height);
    display: flex;
    align-items: center;
    padding: 0 var(--side-padding);
    flex-shrink: 0;
    background: rgba(8, 8, 26, 0.3);
}
html[data-theme="light"] content-top-bar {
    background: #ffffff;
}
content-top-bar .spacer {
    flex: 1;
}
content-top-bar .mobile-back {
    display: none;
    align-items: center;
    gap: 0.5rem;
    color: var(--color-starlight);
    font-weight: 700;
    background: none;
    border: none;
    cursor: pointer;
}

email-header {
    height: var(--sub-header-height);
    display: flex;
    align-items: center;
    padding: 0 var(--side-padding);
    flex-shrink: 0;
    gap: 1rem;
}
html[data-theme="light"] email-header {
    background: #f8fafc;
}
email-header .spacer {
    flex: 0;
}
email-header .email-subject {
    font-size: 1.25rem;
    font-weight: 700;
    color: #f1f5f9;
    margin: 0;
    flex: 1;
    min-width: 0;
    align-self: center;
    line-height: 1.2;
}
html[data-theme="light"] email-header .email-subject {
    color: #0f172a;
}

email-header actions {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    flex-shrink: 0;
    margin-left: auto;
}

email-view {
    flex: 1;
    overflow-y: auto;
    padding: 2rem var(--side-padding);
}

sender-details h3 {
    font-size: 0.875rem;
    font-weight: 600;
    color: #f1f5f9;
    margin: 0;
}
sender-details p {
    font-size: 0.75rem;
    color: #64748b;
    margin: 0;
}
html[data-theme="light"] sender-details h3 {
    color: #0f172a;
}

email-time-full {
    font-size: 0.875rem;
    color: #94a3b8;
}

/* Email Body Typography */
email-body {
    display: block;
    line-height: 1.8;
    color: #cbd5e1;
    font-size: 0.9375rem;
}
email-body p {
    margin-bottom: 1.25rem;
}
email-body ul {
    margin: 1.25rem 0;
    padding-left: 1.5rem;
    list-style-type: disc;
}
email-body li {
    margin-bottom: 0.625rem;
}
email-body strong {
    color: #f1f5f9;
    font-weight: 600;
}
email-body .starlight-brand {
    color: var(--color-starlight);
    font-weight: 600;
}
html[data-theme="light"] email-body {
    color: #475569;
}
html[data-theme="light"] email-body strong {
    color: #1e293b;
}
html[data-theme="light"] .starlight-brand {
    color: #3b82f6;
}

/* Attachments Layout */
attachments {
    display: block;
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}
html[data-theme="light"] attachments {
    border-top-color: #e2e8f0;
}
attachments h3 {
    font-size: 0.875rem;
    font-weight: 600;
    color: #94a3b8;
    margin-bottom: 1rem;
}
.attachments-list {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

actions.content-footer {
    margin-top: 3rem;
    flex-wrap: wrap;
    gap: 0.75rem;
}

actions {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

/* ==========================================================================
   SIDEBAR TOGGLE & OFF-CANVAS
   ========================================================================== */

#sidebar-toggle {
    display: none !important;
}

.nav-toggle {
    display: none;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
}

.nav-toggle i {
    display: inline-block;
    width: 1.25rem;
    height: 1.25rem;
    background-color: #94a3b8;
    transition: background-color 0.2s;
}

.nav-toggle:hover i {
    background-color: var(--color-starlight);
}

html[data-theme="light"] .nav-toggle i {
    background-color: #64748b;
}

.sidebar-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 998;
    display: none;
    cursor: pointer;
}

@media (max-width: 1024px) {
    .email-client {
        grid-template-columns: 1fr !important;
    }
    
    email-sidebar {
        position: fixed;
        left: 0;
        top: 0;
        bottom: 0;
        z-index: 1000;
        width: var(--sidebar-width);
        transform: translateX(-100%);
        transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        display: flex !important;
    }

    html[data-theme="light"] email-sidebar {
        background: #ffffff !important;
    }

    #sidebar-toggle:checked ~ email-sidebar {
        transform: translateX(0);
    }
    
    #sidebar-toggle:checked ~ .sidebar-overlay {
        display: block;
    }

    .list-toggle {
        display: flex;
    }
}

@media (max-width: 768px) {
    .content-toggle {
        display: flex;
    }
}

/* ==========================================================================
   RESPONSIVE DESIGN
   ========================================================================== */

@media (max-width: 768px) {
    .email-client {
        width: 100vw;
    }
    .email-main {
        grid-template-columns: 1fr;
        width: 100vw;
    }

    email-list {
        width: 100vw;
    }
    email-items {
        width: 100vw;
    }
    email-item {
        width: 100%;
    }

    email-content {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        z-index: 100;
        background: #08081a;
        transform: translateX(100%);
        transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
        width: 100vw;
        display: flex;
        flex-direction: column;
    }

    html[data-theme="light"] email-content {
        background: #ffffff !important;
    }

    email-content.mobile-visible {
        transform: translateX(0);
    }
    content-top-bar .mobile-back {
        display: flex;
    }
    
    content-top-bar {
        flex-wrap: wrap;
        gap: 0.5rem;
        padding: 0.5rem 0.75rem;
        min-height: 60px;
        max-height: none;
        height: auto;
    }
    content-top-bar .mobile-back {
        width: 100%;
        flex-basis: 100%;
        margin-bottom: 0.25rem;
    }
    content-top-bar user-cell {
        flex: 1 1 calc(100% - 80px);
        min-width: 150px;
    }
    content-top-bar email-time-full {
        flex: 0 0 auto;
        font-size: 0.75rem;
    }
    
    email-header {
        flex-wrap: wrap;
        padding: 0.5rem 0.75rem;
        min-height: 44px;
        height: auto;
        gap: 0.5rem;
    }
    email-header .email-subject {
        font-size: 1rem;
        order: 1;
        flex: 1 1 100%;
        width: 100%;
        align-self: center;
    }
    email-header .spacer {
        display: none;
    }
    email-header actions {
        order: 2;
        display: flex;
        gap: 0.25rem;
        margin-left: auto;
    }
}