/* ToolSphare Mail Reader - Modern, Accessible & Responsive Styles */

.mr-container {
    max-width: 1380px;
    margin: 0 auto;
    padding: 24px 16px;
    font-family: inherit;
    color: #e2e8f0;
}

/* Header & Intro */
.mr-header {
    margin-bottom: 24px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding-bottom: 20px;
}
.mr-title {
    font-size: 2rem;
    font-weight: 800;
    color: #ffffff;
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 8px;
}
.mr-title-badge {
    font-size: 0.75rem;
    font-weight: 600;
    background: linear-gradient(135deg, #0ea5e9, #6366f1);
    color: #ffffff;
    padding: 4px 10px;
    border-radius: 9999px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.mr-subtitle {
    font-size: 1rem;
    color: #94a3b8;
    max-width: 800px;
    line-height: 1.5;
}

/* Navigation Tabs */
.mr-tabs {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 6px;
    margin-bottom: 24px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.mr-tab-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(30, 41, 59, 0.7);
    color: #94a3b8;
    border: 1px solid rgba(255, 255, 255, 0.08);
    padding: 10px 18px;
    border-radius: 10px;
    font-size: 0.925rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
}
.mr-tab-btn:hover {
    color: #ffffff;
    background: rgba(51, 65, 85, 0.8);
    border-color: rgba(255, 255, 255, 0.15);
}
.mr-tab-btn.active {
    background: #0284c7;
    color: #ffffff;
    border-color: #38bdf8;
    box-shadow: 0 4px 14px rgba(2, 132, 199, 0.35);
}
.mr-tab-badge {
    background: rgba(255, 255, 255, 0.2);
    font-size: 0.72rem;
    padding: 2px 6px;
    border-radius: 9999px;
}

/* Tab Panels */
.mr-panel {
    display: none;
}
.mr-panel.active {
    display: block;
}

/* Card Containers */
.mr-card {
    background: #0f172a;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 16px;
    padding: 24px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.36);
    margin-bottom: 24px;
}

/* Drag and Drop Zone */
.mr-dropzone {
    border: 2px dashed rgba(56, 189, 248, 0.4);
    background: rgba(15, 23, 42, 0.6);
    border-radius: 16px;
    padding: 48px 24px;
    text-align: center;
    cursor: pointer;
    transition: all 0.25s ease;
}
.mr-dropzone:hover, .mr-dropzone.dragover {
    border-color: #38bdf8;
    background: rgba(14, 165, 233, 0.08);
    transform: translateY(-2px);
}
.mr-dropzone-icon {
    font-size: 3rem;
    color: #38bdf8;
    margin-bottom: 12px;
}
.mr-dropzone-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 6px;
}
.mr-dropzone-hint {
    font-size: 0.875rem;
    color: #94a3b8;
}

/* Email Viewer Layout */
.mr-email-view {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
.mr-email-meta {
    background: #1e293b;
    border-radius: 12px;
    padding: 18px 20px;
    border: 1px solid rgba(255, 255, 255, 0.06);
}
.mr-meta-row {
    display: flex;
    margin-bottom: 10px;
    font-size: 0.925rem;
    line-height: 1.4;
}
.mr-meta-row:last-child {
    margin-bottom: 0;
}
.mr-meta-label {
    width: 90px;
    font-weight: 600;
    color: #94a3b8;
    flex-shrink: 0;
}
.mr-meta-val {
    color: #f1f5f9;
    word-break: break-all;
    flex-grow: 1;
}

/* Email Content Tabs */
.mr-subtabs {
    display: flex;
    gap: 8px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding-bottom: 4px;
    margin-bottom: 16px;
}
.mr-subtab-btn {
    background: transparent;
    color: #94a3b8;
    border: none;
    padding: 8px 14px;
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
}
.mr-subtab-btn:hover {
    color: #ffffff;
}
.mr-subtab-btn.active {
    color: #38bdf8;
    border-bottom-color: #38bdf8;
}

/* Sandboxed Iframe Reading Surface */
.mr-iframe-container {
    width: 100%;
    min-height: 480px;
    background: #ffffff;
    border-radius: 12px;
    overflow: hidden;
    position: relative;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.25);
}
.mr-iframe-container iframe {
    width: 100%;
    height: 100%;
    min-height: 480px;
    border: none;
    display: block;
}

/* Remote Image Warning Banner */
.mr-remote-images-bar {
    background: #1e293b;
    border: 1px solid #334155;
    padding: 10px 16px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 0.85rem;
    color: #cbd5e1;
    margin-bottom: 14px;
}
.mr-remote-btn {
    background: #0284c7;
    color: #ffffff;
    border: none;
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
}
.mr-remote-btn:hover {
    background: #0369a1;
}

/* Verification Code Result Cards */
.mr-otp-card {
    background: linear-gradient(135deg, rgba(14, 165, 233, 0.08), rgba(99, 102, 241, 0.08));
    border: 1px solid rgba(56, 189, 248, 0.3);
    border-radius: 16px;
    padding: 20px 24px;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    transition: transform 0.2s ease, border-color 0.2s ease;
}
.mr-otp-card:hover {
    border-color: #38bdf8;
    transform: translateY(-2px);
}
.mr-otp-left {
    display: flex;
    align-items: center;
    gap: 18px;
}
.mr-otp-code-box {
    background: #0f172a;
    border: 2px solid #0284c7;
    border-radius: 12px;
    padding: 12px 20px;
    font-family: 'Fira Code', 'Courier New', monospace;
    font-size: 1.85rem;
    font-weight: 800;
    color: #38bdf8;
    letter-spacing: 0.15em;
    user-select: all;
    box-shadow: 0 4px 16px rgba(2, 132, 199, 0.2);
}
.mr-otp-meta-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 4px;
}
.mr-otp-meta-sub {
    font-size: 0.85rem;
    color: #94a3b8;
    display: flex;
    align-items: center;
    gap: 10px;
}
.mr-otp-badge-confidence {
    font-size: 0.7rem;
    font-weight: 700;
    padding: 2px 8px;
    border-radius: 9999px;
    text-transform: uppercase;
}
.mr-conf-high {
    background: rgba(34, 197, 94, 0.15);
    color: #4ade80;
    border: 1px solid rgba(34, 197, 94, 0.3);
}
.mr-conf-medium {
    background: rgba(234, 179, 8, 0.15);
    color: #facc15;
    border: 1px solid rgba(234, 179, 8, 0.3);
}
.mr-otp-actions {
    display: flex;
    gap: 10px;
}
.mr-btn-copy {
    background: #0284c7;
    color: #ffffff;
    border: none;
    padding: 10px 18px;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: background 0.2s;
}
.mr-btn-copy:hover {
    background: #0369a1;
}

/* Webmail Multi-Pane Layout */
.mr-webmail {
    display: grid;
    grid-template-columns: 240px 340px 1fr;
    min-height: 680px;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 16px;
    overflow: hidden;
    background: #0f172a;
}
@media (max-width: 1024px) {
    .mr-webmail {
        grid-template-columns: 200px 1fr;
    }
    .mr-webmail-pane-read {
        display: none;
    }
}
@media (max-width: 768px) {
    .mr-webmail {
        grid-template-columns: 1fr;
    }
    .mr-webmail-sidebar {
        display: none;
    }
}
.mr-webmail-sidebar {
    background: #090d16;
    border-right: 1px solid rgba(255, 255, 255, 0.06);
    padding: 16px 12px;
}
.mr-folder-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 14px;
    border-radius: 8px;
    color: #94a3b8;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 4px;
    cursor: pointer;
    transition: all 0.15s;
}
.mr-folder-item:hover {
    background: rgba(255, 255, 255, 0.05);
    color: #ffffff;
}
.mr-folder-item.active {
    background: #0284c7;
    color: #ffffff;
    font-weight: 600;
}
.mr-folder-badge {
    background: rgba(255, 255, 255, 0.15);
    font-size: 0.75rem;
    padding: 2px 7px;
    border-radius: 9999px;
}
.mr-webmail-msglist {
    background: #0f172a;
    border-right: 1px solid rgba(255, 255, 255, 0.06);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    max-height: 720px;
}
.mr-msg-item {
    padding: 14px 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.04);
    cursor: pointer;
    transition: background 0.15s;
}
.mr-msg-item:hover {
    background: rgba(255, 255, 255, 0.03);
}
.mr-msg-item.active {
    background: rgba(14, 165, 233, 0.12);
    border-left: 3px solid #38bdf8;
}
.mr-msg-item.unread {
    font-weight: 700;
    color: #ffffff;
}
.mr-msg-sender {
    display: flex;
    justify-content: space-between;
    font-size: 0.875rem;
    margin-bottom: 4px;
}
.mr-msg-subject {
    font-size: 0.925rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin-bottom: 4px;
}
.mr-msg-snippet {
    font-size: 0.8rem;
    color: #94a3b8;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.mr-webmail-pane-read {
    background: #1e293b;
    padding: 24px;
    overflow-y: auto;
    max-height: 720px;
}

/* TOTP Authenticator Vault */
.mr-vault-card {
    background: #0f172a;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 16px;
    padding: 28px;
    max-width: 680px;
    margin: 0 auto;
}
.mr-vault-circle {
    width: 68px;
    height: 68px;
    border-radius: 50%;
    border: 3px solid #38bdf8;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 800;
    color: #38bdf8;
    margin: 0 auto 16px auto;
}
.mr-totp-item {
    background: #1e293b;
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 12px;
    padding: 16px 20px;
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.mr-totp-code {
    font-family: 'Fira Code', monospace;
    font-size: 1.6rem;
    font-weight: 800;
    color: #38bdf8;
    letter-spacing: 0.12em;
}

/* Responsive Utilities */
.mr-grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}
@media (max-width: 768px) {
    .mr-grid-2 {
        grid-template-columns: 1fr;
    }
}


/* UUID & Online Verification Code Reader Extensions */
.mr-uuid-box {
    background: linear-gradient(135deg, rgba(14, 165, 233, 0.08), rgba(99, 102, 241, 0.08));
    border: 1px solid rgba(56, 189, 248, 0.25);
    border-radius: 16px;
    padding: 24px;
    margin-bottom: 24px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}
.mr-uuid-label {
    font-size: 0.95rem;
    font-weight: 700;
    color: #f1f5f9;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.mr-uuid-input-row {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}
.mr-uuid-input {
    flex: 1 1 360px;
    background: #0f172a;
    border: 1px solid #334155;
    border-radius: 10px;
    padding: 14px 18px;
    font-size: 1rem;
    color: #ffffff;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    transition: all 0.2s ease;
}
.mr-uuid-input:focus {
    outline: none;
    border-color: #38bdf8;
    box-shadow: 0 0 0 3px rgba(56, 189, 248, 0.25);
}
.mr-btn-primary {
    background: linear-gradient(135deg, #0284c7, #2563eb);
    color: #ffffff;
    border: none;
    border-radius: 10px;
    padding: 14px 24px;
    font-weight: 700;
    font-size: 0.95rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all 0.2s ease;
}
.mr-btn-primary:hover {
    background: linear-gradient(135deg, #0369a1, #1d4ed8);
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(2, 132, 199, 0.35);
}
.mr-btn-secondary {
    background: rgba(255, 255, 255, 0.08);
    color: #e2e8f0;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 10px;
    padding: 14px 18px;
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s ease;
}
.mr-btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
    color: #ffffff;
}

/* Mailbox Banner */
.mr-mailbox-banner {
    background: #0f172a;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 14px;
    padding: 16px 20px;
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 14px;
}
.mr-email-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 1.15rem;
    font-weight: 700;
    color: #38bdf8;
    word-break: break-all;
}
.mr-auto-refresh {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: #94a3b8;
    background: rgba(255, 255, 255, 0.04);
    padding: 6px 12px;
    border-radius: 8px;
}
.mr-pulse-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #22c55e;
    box-shadow: 0 0 10px #22c55e;
    animation: mrPulse 2s infinite;
}
@keyframes mrPulse {
    0% { opacity: 0.4; transform: scale(0.9); }
    50% { opacity: 1; transform: scale(1.2); }
    100% { opacity: 0.4; transform: scale(0.9); }
}

/* Hero Code Banner */
.mr-hero-code {
    background: linear-gradient(135deg, rgba(34, 197, 94, 0.12), rgba(14, 165, 233, 0.12));
    border: 2px solid #22c55e;
    border-radius: 16px;
    padding: 22px 28px;
    margin-bottom: 22px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 18px;
    box-shadow: 0 12px 35px rgba(34, 197, 94, 0.18);
}
.mr-hero-code-left {
    display: flex;
    align-items: center;
    gap: 18px;
}
.mr-hero-code-icon {
    font-size: 2.4rem;
}
.mr-hero-code-title {
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: #4ade80;
    margin-bottom: 4px;
}
.mr-hero-code-digits {
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    font-size: 2.4rem;
    font-weight: 900;
    letter-spacing: 0.18em;
    color: #ffffff;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
}
.mr-hero-code-meta {
    font-size: 0.85rem;
    color: #94a3b8;
    margin-top: 4px;
}
.mr-btn-copy-code {
    background: #22c55e;
    color: #064e3b;
    border: none;
    border-radius: 10px;
    padding: 14px 26px;
    font-size: 1.05rem;
    font-weight: 800;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all 0.2s ease;
    box-shadow: 0 6px 16px rgba(34, 197, 94, 0.35);
}
.mr-btn-copy-code:hover {
    background: #16a34a;
    color: #ffffff;
    transform: translateY(-2px);
    box-shadow: 0 8px 22px rgba(34, 197, 94, 0.45);
}

/* Folder Pills */
.mr-folder-bar {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 8px;
    margin-bottom: 20px;
}
.mr-folder-pill {
    background: #1e293b;
    color: #94a3b8;
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 9999px;
    padding: 8px 16px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    white-space: nowrap;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.15s ease;
}
.mr-folder-pill:hover {
    background: #334155;
    color: #ffffff;
}
.mr-folder-pill.active {
    background: #0284c7;
    color: #ffffff;
    border-color: #38bdf8;
    box-shadow: 0 4px 12px rgba(2, 132, 199, 0.3);
}
.mr-folder-count {
    background: rgba(0, 0, 0, 0.25);
    padding: 2px 7px;
    border-radius: 9999px;
    font-size: 0.75rem;
}

/* Two-column split layout */
.mr-workspace {
    display: grid;
    grid-template-columns: 380px 1fr;
    gap: 20px;
    min-height: 580px;
}
@media (max-width: 900px) {
    .mr-workspace {
        grid-template-columns: 1fr;
    }
}
.mr-msg-column {
    background: #0f172a;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 14px;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    max-height: 700px;
}
.mr-msg-filter {
    padding: 12px 14px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    background: rgba(255, 255, 255, 0.02);
}
.mr-msg-filter input {
    width: 100%;
    padding: 8px 12px;
    background: #1e293b;
    border: 1px solid #334155;
    border-radius: 8px;
    color: #ffffff;
    font-size: 0.85rem;
}
.mr-msg-scroll {
    flex: 1;
    overflow-y: auto;
    padding: 8px;
}
.mr-msg-card {
    background: #1e293b;
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 10px;
    padding: 12px 14px;
    margin-bottom: 8px;
    cursor: pointer;
    transition: all 0.15s ease;
}
.mr-msg-card:hover {
    background: #334155;
    border-color: rgba(56, 189, 248, 0.3);
}
.mr-msg-card.selected {
    background: #1e3a5f;
    border-color: #38bdf8;
    box-shadow: 0 4px 14px rgba(56, 189, 248, 0.2);
}
.mr-msg-card-top {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 4px;
}
.mr-msg-card-from {
    font-weight: 700;
    color: #ffffff;
    font-size: 0.9rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 220px;
}
.mr-msg-card-date {
    font-size: 0.75rem;
    color: #64748b;
}
.mr-msg-card-subject {
    font-size: 0.85rem;
    font-weight: 600;
    color: #cbd5e1;
    margin-bottom: 6px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.mr-msg-card-snippet {
    font-size: 0.8rem;
    color: #94a3b8;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.mr-card-otp-badge {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    background: rgba(34, 197, 94, 0.2);
    color: #4ade80;
    border: 1px solid rgba(34, 197, 94, 0.4);
    padding: 2px 8px;
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 700;
    margin-top: 6px;
    font-family: ui-monospace, SFMono-Regular, monospace;
}

/* Reading Pane */
.mr-read-column {
    background: #0f172a;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 14px;
    padding: 24px;
    display: flex;
    flex-direction: column;
    max-height: 700px;
    overflow-y: auto;
}
.mr-read-head {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding-bottom: 16px;
    margin-bottom: 18px;
}
.mr-read-subject {
    font-size: 1.35rem;
    font-weight: 800;
    color: #ffffff;
    margin-bottom: 10px;
}
.mr-read-meta-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
    font-size: 0.875rem;
}
.mr-read-from {
    color: #94a3b8;
}
.mr-read-from strong {
    color: #ffffff;
}
.mr-read-actions {
    display: flex;
    gap: 8px;
}
.mr-read-tabs {
    display: flex;
    gap: 6px;
    margin-bottom: 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    padding-bottom: 8px;
}
.mr-read-tab {
    background: transparent;
    border: none;
    color: #94a3b8;
    padding: 6px 12px;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s ease;
}
.mr-read-tab.active {
    background: #1e293b;
    color: #38bdf8;
}
.mr-read-body {
    flex: 1;
    min-height: 250px;
    font-size: 0.95rem;
    line-height: 1.65;
    color: #cbd5e1;
    white-space: pre-wrap;
    word-break: break-word;
    font-family: inherit;
    background: #131d31;
    padding: 16px;
    border-radius: 8px;
    overflow-y: auto;
}
.mr-read-links-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.mr-link-btn {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: #1e293b;
    border: 1px solid rgba(255, 255, 255, 0.06);
    padding: 10px 14px;
    border-radius: 8px;
    color: #38bdf8;
    text-decoration: none;
    font-size: 0.875rem;
    word-break: break-all;
    transition: all 0.15s ease;
}
.mr-link-btn:hover {
    background: #334155;
    border-color: #38bdf8;
}

/* Toast notification */
.mr-toast {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background: #22c55e;
    color: #064e3b;
    padding: 12px 20px;
    border-radius: 10px;
    font-weight: 700;
    font-size: 0.95rem;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
    z-index: 9999;
    display: flex;
    align-items: center;
    gap: 8px;
    animation: mrFadeIn 0.25s ease;
}
@keyframes mrFadeIn {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}


/* ==========================================================================
   ENHANCED MOBILE & TABLET RESPONSIVE SYSTEM
   ========================================================================== */

/* Universal Touch & Scroll Smoothing */
.mr-tabs,
.mr-folder-bar,
.mr-read-tabs {
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    scroll-behavior: smooth;
}
.mr-tabs::-webkit-scrollbar,
.mr-folder-bar::-webkit-scrollbar,
.mr-read-tabs::-webkit-scrollbar {
    display: none;
    width: 0;
    height: 0;
}

.mr-tab-btn,
.mr-folder-pill,
.mr-read-tab {
    flex: 0 0 auto;
    white-space: nowrap;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}

/* Mobile Pane Toggle (Hidden on desktop > 900px) */
.mr-mobile-pane-toggle {
    display: none;
    margin-bottom: 14px;
    background: #0f172a;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    padding: 4px;
    gap: 4px;
}
.mr-mobile-toggle-btn {
    flex: 1;
    background: transparent;
    color: #94a3b8;
    border: none;
    padding: 10px 14px;
    font-size: 0.875rem;
    font-weight: 700;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.15s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    min-height: 42px;
}
.mr-mobile-toggle-btn.active {
    background: #0284c7;
    color: #ffffff;
    box-shadow: 0 2px 10px rgba(2, 132, 199, 0.35);
}
.mr-back-to-list-btn {
    display: none;
    background: rgba(56, 189, 248, 0.12);
    color: #38bdf8;
    border: 1px solid rgba(56, 189, 248, 0.3);
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 0.825rem;
    font-weight: 700;
    cursor: pointer;
    align-items: center;
    gap: 6px;
    margin-bottom: 12px;
    width: fit-content;
    transition: all 0.15s ease;
}
.mr-back-to-list-btn:hover {
    background: rgba(56, 189, 248, 0.2);
    color: #ffffff;
}

/* Tablet Breakpoint (max-width: 900px) */
@media (max-width: 900px) {
    .mr-mobile-pane-toggle {
        display: flex;
    }
    .mr-back-to-list-btn {
        display: inline-flex;
    }
    .mr-workspace {
        display: block;
        min-height: auto;
    }
    .mr-msg-column {
        max-height: 520px;
        margin-bottom: 16px;
    }
    .mr-read-column {
        max-height: 620px;
        padding: 20px 16px;
    }
    /* Dynamic Mobile Pane Visibility */
    .mr-workspace.mobile-view-read .mr-msg-column {
        display: none !important;
    }
    .mr-workspace.mobile-view-read .mr-read-column {
        display: flex !important;
    }
    .mr-workspace.mobile-view-list .mr-msg-column {
        display: flex !important;
    }
    .mr-workspace.mobile-view-list .mr-read-column {
        display: none !important;
    }
}

/* Smartphone Breakpoint (max-width: 640px) */
@media (max-width: 640px) {
    .mr-container {
        padding: 8px 2px;
    }
    .mr-header {
        margin-bottom: 16px;
        padding-bottom: 12px;
    }
    .mr-title {
        font-size: 1.45rem;
        flex-direction: column;
        align-items: flex-start;
        gap: 6px;
    }
    .mr-title-badge {
        font-size: 0.7rem;
        padding: 3px 8px;
    }
    .mr-subtitle {
        font-size: 0.875rem;
        line-height: 1.5;
    }

    /* Tabs */
    .mr-tabs {
        margin-bottom: 16px;
        gap: 6px;
    }
    .mr-tab-btn {
        padding: 8px 12px;
        font-size: 0.8rem;
    }

    /* UUID Box */
    .mr-uuid-box {
        padding: 16px 12px;
        border-radius: 12px;
        margin-bottom: 16px;
    }
    .mr-uuid-label {
        font-size: 0.875rem;
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }
    .mr-uuid-input-row {
        flex-direction: column;
        gap: 8px;
    }
    .mr-uuid-input {
        width: 100%;
        flex: 1 1 100%;
        padding: 12px 14px;
        font-size: 16px !important; /* Critical: Prevent iOS Safari Auto-Zoom */
        box-sizing: border-box;
    }
    .mr-btn-primary {
        width: 100%;
        justify-content: center;
        padding: 12px 16px;
        font-size: 0.95rem;
        min-height: 46px;
    }
    .mr-uuid-actions-sub {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 8px;
        width: 100%;
    }
    .mr-btn-secondary {
        justify-content: center;
        padding: 10px 12px;
        font-size: 0.825rem;
        min-height: 42px;
    }

    /* Mailbox Summary Banner */
    .mr-mailbox-banner {
        padding: 12px 14px;
        flex-direction: column;
        align-items: stretch;
        gap: 12px;
    }
    .mr-mailbox-head-group {
        display: flex;
        flex-direction: column;
        gap: 10px;
        width: 100%;
    }
    .mr-email-badge {
        font-size: 1rem;
        width: 100%;
        word-break: break-all;
    }
    .mr-mailbox-banner-actions {
        display: flex;
        gap: 8px;
        width: 100%;
    }
    .mr-mailbox-banner-actions button {
        flex: 1;
        justify-content: center;
        min-height: 40px;
    }
    .mr-mailbox-status-row {
        display: flex;
        justify-content: space-between;
        align-items: center;
        gap: 8px;
        border-top: 1px solid rgba(255, 255, 255, 0.06);
        padding-top: 10px;
        width: 100%;
    }

    /* Hero Verification Code Card */
    .mr-hero-code {
        padding: 16px 14px;
        border-radius: 12px;
        flex-direction: column;
        align-items: stretch;
        gap: 14px;
    }
    .mr-hero-code-left {
        gap: 12px;
    }
    .mr-hero-code-icon {
        font-size: 2rem;
    }
    .mr-hero-code-digits {
        font-size: clamp(1.6rem, 7vw, 2.1rem);
        letter-spacing: 0.08em;
    }
    .mr-btn-copy-code {
        width: 100%;
        justify-content: center;
        padding: 12px 16px;
        font-size: 0.95rem;
        min-height: 46px;
    }

    /* Folder Pills */
    .mr-folder-bar {
        gap: 6px;
        margin-bottom: 12px;
    }
    .mr-folder-pill {
        padding: 6px 12px;
        font-size: 0.775rem;
        min-height: 38px;
    }

    /* Message List */
    .mr-msg-card {
        padding: 10px 12px;
    }
    .mr-msg-card-from {
        max-width: 160px;
        font-size: 0.85rem;
    }
    .mr-msg-filter input {
        font-size: 16px !important; /* Critical: Prevent iOS Safari Auto-Zoom */
        padding: 10px 12px;
    }

    /* Reading Pane */
    .mr-read-head {
        padding-bottom: 12px;
        margin-bottom: 12px;
    }
    .mr-read-subject {
        font-size: 1.15rem;
        line-height: 1.35;
    }
    .mr-read-meta-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }
    .mr-read-tabs {
        gap: 4px;
    }
    .mr-read-tab {
        padding: 6px 10px;
        font-size: 0.8rem;
    }
    .mr-read-body {
        padding: 12px;
        font-size: 0.875rem;
    }
    .mr-link-btn {
        padding: 10px 12px;
        font-size: 0.825rem;
    }

    /* Local File Dropzone */
    .mr-dropzone {
        padding: 24px 14px;
    }
    .mr-dropzone-icon {
        font-size: 2rem;
    }
    .mr-dropzone-title {
        font-size: 1.05rem;
    }
    .mr-dropzone-hint {
        font-size: 0.775rem;
    }

    /* Toast */
    .mr-toast {
        left: 12px;
        right: 12px;
        bottom: 12px;
        justify-content: center;
        font-size: 0.875rem;
    }
}

/* Ultra-Compact Screens (iPhone 5/SE1 / Foldables, max-width: 380px) */
@media (max-width: 380px) {
    .mr-hero-code-digits {
        font-size: 1.45rem;
        letter-spacing: 0.04em;
    }
    .mr-msg-card-from {
        max-width: 120px;
    }
}