:root {
    --color-bg-default: #0d1117;
    --color-bg-subtle: #161b22;
    --color-bg-muted: #21262d;
    --color-canvas-default: #0d1117;
    --color-canvas-subtle: #161b22;
    --color-border-default: #30363d;
    --color-border-muted: #21262d;
    --color-fg-default: #c9d1d9;
    --color-fg-muted: #8b949e;
    --color-fg-subtle: #6e7681;
    --color-accent-fg: #2f81f7;
    --color-accent-emphasis: #1f6feb;
    --color-danger-fg: #f85149;
    --color-success-fg: #3fb950;
    --color-attention-fg: #d2a334;
    --shadow-sm: 0 1px 0 rgba(0,0,0,0.2);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.4);
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 12px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans', Helvetica, Arial, sans-serif;
    background-color: var(--color-bg-default);
    color: var(--color-fg-default);
    line-height: 1.5;
}

.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
.header {
    background: var(--color-bg-subtle);
    border-bottom: 1px solid var(--color-border-default);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1280px;
    margin: 0 auto;
    padding: 12px 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
    font-size: 18px;
}

.logo-text {
    background: linear-gradient(135deg, #2f81f7, #58a6ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--color-fg-default);
    cursor: pointer;
    padding: 8px;
}

/* Navigation */
.nav-menu {
    background: var(--color-bg-subtle);
    border-bottom: 1px solid var(--color-border-default);
    position: sticky;
    top: 57px;
    z-index: 99;
}

.nav-menu ul {
    max-width: 1280px;
    margin: 0 auto;
    display: flex;
    list-style: none;
    padding: 0 16px;
    gap: 8px;
}

.nav-menu li {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    cursor: pointer;
    color: var(--color-fg-muted);
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
}

.nav-menu li.active {
    color: var(--color-fg-default);
    border-bottom-color: var(--color-accent-fg);
}

.nav-menu li:hover:not(.active) {
    color: var(--color-fg-default);
    background: var(--color-bg-muted);
}

/* Main Content */
.main-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 24px 16px;
    flex: 1;
    width: 100%;
}

/* Loading State */
.loading-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 60px 20px;
    text-align: center;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--color-border-muted);
    border-top-color: var(--color-accent-fg);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 16px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.spinner-small {
    width: 20px;
    height: 20px;
    border: 2px solid var(--color-border-muted);
    border-top-color: var(--color-accent-fg);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 12px;
}

/* Welcome Banner */
.welcome-banner {
    background: linear-gradient(135deg, var(--color-bg-subtle), var(--color-bg-default));
    border: 1px solid var(--color-border-default);
    border-radius: var(--radius-xl);
    padding: 24px;
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    gap: 20px;
}

.welcome-avatar img {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--color-accent-fg);
}

.welcome-info h2 {
    font-size: 20px;
    margin-bottom: 4px;
}

.verified-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    color: var(--color-success-fg);
    background: rgba(63, 185, 80, 0.1);
    padding: 4px 10px;
    border-radius: 20px;
}

/* Cards */
.card {
    background: var(--color-bg-subtle);
    border: 1px solid var(--color-border-default);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 24px;
}

.card h3 {
    margin-bottom: 20px;
    font-size: 18px;
}

/* Form Elements */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--color-fg-muted);
    font-size: 14px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 10px 12px;
    background: var(--color-canvas-default);
    border: 1px solid var(--color-border-default);
    border-radius: var(--radius-md);
    color: var(--color-fg-default);
    font-family: inherit;
    font-size: 14px;
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-accent-fg);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.form-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: var(--radius-md);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    font-size: 14px;
}

.btn-primary {
    background: var(--color-accent-fg);
    color: white;
}

.btn-primary:hover {
    background: var(--color-accent-emphasis);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-icon {
    background: none;
    border: none;
    color: var(--color-fg-muted);
    cursor: pointer;
    padding: 8px;
    border-radius: var(--radius-sm);
    transition: all 0.2s;
}

.btn-icon:hover {
    background: var(--color-bg-muted);
    color: var(--color-fg-default);
}

/* Inbox Section */
.inbox-section {
    background: var(--color-bg-subtle);
    border: 1px solid var(--color-border-default);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.inbox-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--color-border-default);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.inbox-header h3 {
    margin: 0;
}

/* Messages List */
.messages-list {
    max-height: 600px;
    overflow-y: auto;
}

.message-card {
    display: flex;
    gap: 16px;
    padding: 20px 24px;
    border-bottom: 1px solid var(--color-border-muted);
    transition: background 0.2s;
}

.message-card:hover {
    background: var(--color-bg-muted);
}

.message-card.unread {
    background: rgba(47, 129, 247, 0.05);
    border-left: 3px solid var(--color-accent-fg);
}

.message-avatar img {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    object-fit: cover;
}

.message-content {
    flex: 1;
}

.message-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    flex-wrap: wrap;
    margin-bottom: 8px;
}

.message-sender {
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.verified-icon {
    color: var(--color-accent-fg);
    font-size: 14px;
}

.message-time {
    font-size: 12px;
    color: var(--color-fg-muted);
}

.message-phone {
    font-size: 12px;
    color: var(--color-fg-muted);
    margin-bottom: 8px;
}

.message-text {
    color: var(--color-fg-default);
    line-height: 1.5;
}

.reply-indicator {
    margin-top: 8px;
    font-size: 12px;
    color: var(--color-accent-fg);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.empty-state {
    text-align: center;
    padding: 48px 20px;
    color: var(--color-fg-muted);
}

.loading-messages {
    text-align: center;
    padding: 40px;
    color: var(--color-fg-muted);
}

/* Sign In Prompt */
.signin-prompt {
    text-align: center;
}

/* Notification Badge */
.notification-badge {
    position: relative;
}

.notification-count {
    position: absolute;
    top: 4px;
    right: 4px;
    background: var(--color-danger-fg);
    color: white;
    font-size: 10px;
    font-weight: bold;
    padding: 2px 5px;
    border-radius: 20px;
    min-width: 18px;
    text-align: center;
}

/* Heartbeat Animation */
@keyframes heartbeat {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}

.heartbeat {
    animation: heartbeat 1.5s ease infinite;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .mobile-menu-btn {
        display: block;
    }
    
    .nav-menu {
        position: fixed;
        top: 57px;
        left: -100%;
        width: 80%;
        height: calc(100vh - 57px);
        transition: left 0.3s ease;
        z-index: 200;
        overflow-y: auto;
    }
    
    .nav-menu.open {
        left: 0;
    }
    
    .nav-menu ul {
        flex-direction: column;
        padding: 8px;
    }
    
    .nav-menu li {
        padding: 12px 16px;
    }
    
    .welcome-banner {
        flex-direction: column;
        text-align: center;
    }
    
    .form-actions {
        flex-direction: column;
    }
    
    .message-limit-badge {
        width: 100%;
        justify-content: center;
    }
    
    .btn-primary {
        width: 100%;
        justify-content: center;
    }
    
    .message-card {
        flex-direction: column;
        gap: 12px;
    }
    
    .message-avatar {
        align-self: flex-start;
    }
    
    .inbox-header {
        flex-direction: column;
        gap: 12px;
        text-align: center;
    }
}

/* Desktop adjustments */
@media (min-width: 769px) {
    .nav-menu {
        position: relative;
        top: auto;
    }
    
    .nav-menu ul {
        justify-content: flex-start;
    }
}

/* Profile styles for the auth module integration */
#sb-profile {
    margin-left: auto;
}

.sb-profile-trigger {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 6px 12px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: background 0.2s;
}

.sb-profile-trigger:hover {
    background: var(--color-bg-muted);
}

.sb-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    object-fit: cover;
}

.sb-profile-info {
    display: flex;
    flex-direction: column;
}

.sb-name {
    font-size: 14px;
    font-weight: 500;
}

.sb-email {
    font-size: 12px;
    color: var(--color-fg-muted);
}

.sb-chevron {
    width: 16px;
    height: 16px;
    transition: transform 0.2s;
}

.sb-profile-trigger.active .sb-chevron {
    transform: rotate(180deg);
}

.sb-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 8px;
    background: var(--color-bg-subtle);
    border: 1px solid var(--color-border-default);
    border-radius: var(--radius-lg);
    min-width: 260px;
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    display: none;
}

.sb-dropdown.active {
    display: block;
}

.sb-dropdown-header {
    padding: 16px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.sb-dropdown-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    object-fit: cover;
}

.sb-dropdown-name {
    font-weight: 600;
}

.sb-dropdown-email {
    font-size: 12px;
    color: var(--color-fg-muted);
}

.sb-dropdown-divider {
    height: 1px;
    background: var(--color-border-muted);
    margin: 8px 0;
}

.sb-logout-btn {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: none;
    border: none;
    color: var(--color-danger-fg);
    cursor: pointer;
    transition: background 0.2s;
}

.sb-logout-btn:hover {
    background: var(--color-bg-muted);
}

.sb-logout-btn svg {
    width: 18px;
    height: 18px;
}

/* Profile in mobile nav */
.sb-profile-nav-item {
    border-top: 1px solid var(--color-border-muted);
    margin-top: 8px;
    padding-top: 8px;
}

.sb-profile-nav-item #sb-profile {
    margin-left: 0;
    width: 100%;
}

.sb-profile-nav-item .sb-profile-trigger {
    padding: 8px;
}

.sb-profile-nav-item .sb-dropdown {
    position: static;
    box-shadow: none;
    margin-top: 8px;
}

        .message-limit-badge {
            background: var(--color-bg-muted);
            padding: 6px 12px;
            border-radius: 20px;
            font-size: 0.75rem;
            color: var(--color-fg-muted);
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .message-limit-badge.warning {
            background: rgba(210, 153, 34, 0.2);
            color: #d2a334;
        }
        .message-limit-badge.danger {
            background: rgba(248, 81, 73, 0.2);
            color: #f85149;
        }
        .remaining-count {
            font-weight: 600;
        }
        .char-counter {
            font-size: 0.7rem;
            text-align: right;
            margin-top: 4px;
            color: var(--color-fg-muted);
        }
        .char-counter.warning {
            color: #d2a334;
        }
        .char-counter.danger {
            color: #f85149;
        }
        .message-card {
            transition: all 0.2s ease;
        }
        .message-card.unread {
            border-left: 3px solid #2f81f7;
            background: var(--color-canvas-subtle);
        }
        .heartbeat {
            animation: heartbeat 1.5s ease infinite;
        }
        @keyframes heartbeat {
            0% { transform: scale(1); }
            50% { transform: scale(1.1); }
            100% { transform: scale(1); }
        }
        .notification-badge {
            position: relative;
            display: inline-flex;
            align-items: center;
            justify-content: center;
        }
        .notification-count {
            position: absolute;
            top: -8px;
            right: -12px;
            background: #f85149;
            color: white;
            font-size: 0.7rem;
            font-weight: bold;
            padding: 2px 6px;
            border-radius: 20px;
            min-width: 18px;
            text-align: center;
        }
        .inbox-header-icon {
            cursor: pointer;
            transition: opacity 0.2s;
        }
        .inbox-header-icon:hover {
            opacity: 0.7;
        }
        .toast {
            position: fixed;
            bottom: 20px;
            left: 50%;
            transform: translateX(-50%);
            background: var(--color-canvas-default);
            color: var(--color-fg-default);
            padding: 12px 20px;
            border-radius: 8px;
            box-shadow: var(--shadow-lg);
            z-index: 1000;
            animation: slideUp 0.3s ease;
            border-left: 3px solid;
            max-width: 90%;
            text-align: center;
        }
        .toast.success { border-left-color: #3fb950; }
        .toast.error { border-left-color: #f85149; }
        .toast.info { border-left-color: #2f81f7; }
        @keyframes slideUp {
            from { opacity: 0; transform: translateX(-50%) translateY(20px); }
            to { opacity: 1; transform: translateX(-50%) translateY(0); }
        }
        .empty-state {
            text-align: center;
            padding: 48px 20px;
            color: var(--color-fg-muted);
        }
        .empty-state svg {
            margin-bottom: 16px;
            opacity: 0.5;
        }
        .verified-icon {
            display: inline-flex;
            align-items: center;
            margin-left: 4px;
            color: #2f81f7;
        }
        .message-input-container textarea {
            resize: vertical;
            min-height: 100px;
        }
        .send-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }