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

html,
body {
    height: 100%;
}

body {
    font-family: var(--font-body);
    background-color: var(--color-bg);
    color: var(--color-text);
    height: 100vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 9999;
    opacity: 0.03;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
}

*:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
    border-radius: 2px;
}

.app-header {
    background-color: var(--color-bg-elevated);
    min-height: var(--header-height);
    padding: 0 24px;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    z-index: 20;
    overflow: hidden;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--color-text-secondary);
    font-weight: 600;
    white-space: nowrap;
}

.header-brand strong {
    color: var(--color-accent);
}

#doc-id-badge {
    opacity: 0.55;
    font-family: var(--font-code);
    letter-spacing: 0.08em;
}

.header-actions {
    display: flex;
    gap: 12px;
    align-items: center;
    justify-content: flex-end;
    flex-wrap: nowrap;
    min-width: 0;
    overflow-x: auto;
    padding-bottom: 2px;
    scrollbar-width: none;
}

.header-actions::-webkit-scrollbar {
    display: none;
}

.btn,
.preview-mode-btn {
    font-family: var(--font-body);
}

.btn {
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-accent);
    padding: 8px 16px;
    min-height: 36px;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 0.8125rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    transition: all var(--transition-base) var(--ease-out);
    display: inline-flex;
    align-items: center;
    gap: 8px;
    position: relative;
    flex: 0 0 auto;
}

.btn:hover {
    background: color-mix(in srgb, var(--color-accent) 10%, transparent);
    border-color: var(--color-accent);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn:active {
    transform: translateY(0);
}

.btn.icon-only {
    padding: 8px 10px;
    gap: 6px;
}

.btn svg,
.preview-mode-btn svg {
    display: block;
    flex: 0 0 auto;
}

.btn.active {
    background: color-mix(in srgb, var(--color-accent) 14%, transparent);
    border-color: color-mix(in srgb, var(--color-accent) 78%, var(--color-border));
    color: var(--color-text);
}

.preview-mode-toggle {
    display: inline-flex;
    align-items: center;
    gap: 2px;
    padding: 2px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    background: color-mix(in srgb, var(--color-bg-soft) 72%, transparent);
    flex: 0 0 auto;
}

.preview-mode-btn {
    border: 0;
    background: transparent;
    color: var(--color-text-secondary);
    min-height: 32px;
    padding: 6px 12px;
    border-radius: 6px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 7px;
    font-size: 0.75rem;
    line-height: 1;
    font-weight: 700;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    transition: color var(--transition-base) var(--ease-out), background var(--transition-base) var(--ease-out);
}

.preview-mode-btn:hover {
    color: var(--color-text);
    background: color-mix(in srgb, var(--color-accent) 9%, transparent);
}

.preview-mode-btn[aria-checked="true"],
.preview-mode-btn[aria-pressed="true"] {
    background: var(--color-accent);
    color: #111214;
}

.visually-hidden {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0 0 0 0) !important;
    white-space: nowrap !important;
    border: 0 !important;
}

#save-indicator {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--color-success);
    opacity: 0.55;
    transition: opacity var(--transition-base);
    white-space: nowrap;
    flex: 0 0 auto;
}

#save-indicator.is-hot {
    opacity: 1;
}

.main-content {
    display: flex;
    flex: 1;
    min-height: 0;
    overflow: hidden;
    position: relative;
}

#editor-container {
    width: 45%;
    min-width: var(--collapsed-width);
    display: flex;
    flex-direction: column;
    background-color: var(--color-bg);
    transition: width var(--transition-base) var(--ease-out);
    border-right: 1px solid var(--color-border);
    position: relative;
}

#editor-container.collapsed {
    width: var(--collapsed-width) !important;
}

#collapse-btn {
    position: absolute;
    top: 16px;
    right: 16px;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--color-text-secondary);
    background: transparent;
    border: 0;
    border-radius: var(--radius-sm);
    transition: all var(--transition-base) var(--ease-out);
    z-index: 10;
}

#collapse-btn:hover {
    color: var(--color-accent);
    background: var(--color-bg-elevated);
}

#editor-container.collapsed #collapse-btn {
    display: none;
}

#editor {
    flex: 1;
    min-height: 0;
    background-color: transparent;
    color: var(--color-text-secondary);
    border: none;
    padding: 32px;
    font-family: var(--font-code);
    font-size: 0.8125rem;
    resize: none;
    outline: none;
    line-height: 1.7;
}

#editor:focus {
    color: var(--color-text);
}

#editor-container.collapsed #editor,
#editor-container.collapsed .color-inspector {
    display: none;
}

#expand-btn {
    display: none;
    width: 100%;
    height: var(--header-height);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    gap: 4px;
    border: 0;
    background: transparent;
}

.bar {
    width: 18px;
    height: 2px;
    background-color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
}

#editor-container.collapsed #expand-btn {
    display: flex;
}

#expand-btn:hover .bar {
    background-color: var(--color-accent);
}

#resizer {
    width: 4px;
    flex: 0 0 4px;
    cursor: col-resize;
    background-color: var(--resizer-color);
    z-index: 10;
    transition: background-color var(--transition-base);
}

#resizer:hover,
.resizing #resizer {
    background-color: var(--color-accent);
}

#preview {
    flex: 1 1 auto;
    min-width: min(var(--preview-min-width), 45vw);
    width: 100%;
    padding: clamp(28px, 5vw, 64px) clamp(20px, 6vw, 72px);
    overflow-y: auto;
    background-color: var(--color-bg);
    font-family: var(--font-body);
    font-size: 1.125rem;
    line-height: 1.7;
    color: var(--color-text);
}

#preview .rendered-content {
    width: 100%;
    max-width: min(1120px, 100%);
    margin: 0 auto;
}

#preview .rendered-content.is-raw {
    max-width: min(980px, 100%);
}

.raw-markdown-preview {
    margin: 0;
    width: 100%;
    min-height: min(720px, calc(100vh - 180px));
    padding: 0;
    border: 0;
    border-radius: 0;
    background: transparent;
    color: var(--color-text-secondary);
    font: 0.9rem/1.78 var(--font-code);
    white-space: pre-wrap;
    overflow: visible;
}

.main-content.document-view #editor-container,
.main-content.document-view #resizer {
    display: none;
}

.main-content.document-view #preview {
    min-width: 0;
    width: 100%;
}

.main-content.document-view #preview .rendered-content {
    max-width: min(900px, 100%);
}

.main-content.document-view #preview .rendered-content.is-raw {
    max-width: min(980px, 100%);
}

.resizing {
    cursor: col-resize;
    user-select: none;
}

.color-inspector {
    border-top: 1px solid var(--color-border);
    padding: 12px 16px 16px;
    background: color-mix(in srgb, var(--color-bg-elevated) 80%, transparent);
}

.color-inspector-title {
    font: 600 11px/1 var(--font-body);
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--color-text-muted);
    margin-bottom: 10px;
}

.color-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.color-chip {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    border: 1px solid var(--color-border);
    background: var(--color-bg);
    color: var(--color-text-secondary);
    border-radius: var(--radius-pill);
    padding: 5px 9px;
    font: 12px/1 var(--font-code);
    cursor: pointer;
}

.color-dot {
    width: 12px;
    height: 12px;
    border-radius: 999px;
    border: 1px solid var(--color-border);
    background: repeating-linear-gradient(45deg, transparent, transparent 2px, var(--color-border) 2px, var(--color-border) 4px);
}

.color-chip em {
    font-family: var(--font-body);
    font-style: normal;
    color: var(--color-danger);
    font-size: 11px;
}

.print-frame {
    position: fixed;
    right: 0;
    bottom: 0;
    width: 0;
    height: 0;
    border: 0;
    opacity: 0;
    pointer-events: none;
}

::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--color-border);
    border-radius: var(--radius-pill);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-secondary);
}

@media (max-width: 1599px) {
    .app-header {
        padding-inline: 18px;
        gap: 12px;
    }

    .header-actions {
        gap: 6px;
    }

    .btn {
        width: 36px;
        min-width: 36px;
        height: 36px;
        min-height: 36px;
        padding: 0;
        justify-content: center;
        gap: 0;
    }

    .btn.icon-only {
        padding: 0;
    }

    .preview-mode-toggle {
        gap: 1px;
    }

    .preview-mode-btn {
        width: 36px;
        min-width: 36px;
        height: 32px;
        min-height: 32px;
        padding: 0;
        gap: 0;
    }

    .btn .btn-label,
    .preview-mode-btn .btn-label {
        position: absolute !important;
        width: 1px !important;
        height: 1px !important;
        padding: 0 !important;
        margin: -1px !important;
        overflow: hidden !important;
        clip: rect(0 0 0 0) !important;
        white-space: nowrap !important;
        border: 0 !important;
    }

    #save-indicator {
        margin-left: 2px;
        font-size: 0.62rem;
        letter-spacing: 0.08em;
        opacity: 0.48;
    }
}

@media (max-width: 900px) {
    body {
        overflow: auto;
        height: auto;
        min-height: 100vh;
    }

    .app-header {
        height: auto;
        min-height: 0;
        padding: 10px 12px;
        align-items: flex-start;
        flex-direction: column;
        gap: 8px;
    }

    .header-brand {
        width: 100%;
        gap: 8px;
        overflow: hidden;
        font-size: 0.6875rem;
        letter-spacing: 1.4px;
    }

    .header-brand span {
        overflow: hidden;
        text-overflow: ellipsis;
    }

    .header-actions {
        width: 100%;
        justify-content: flex-start;
        gap: 4px;
    }

    .btn {
        width: 34px;
        min-width: 34px;
        height: 34px;
        min-height: 34px;
        padding: 0;
        justify-content: center;
        gap: 0;
        flex: 0 0 auto;
    }

    .btn.icon-only {
        padding: 0;
    }

    .preview-mode-toggle {
        flex: 0 0 auto;
        gap: 1px;
        padding: 2px;
    }

    .preview-mode-btn {
        width: 34px;
        min-width: 34px;
        height: 30px;
        min-height: 30px;
        padding: 0;
        gap: 0;
    }

    #save-indicator {
        margin-left: 2px;
        align-self: center;
        font-size: 0.58rem;
        letter-spacing: 0.08em;
        opacity: 0.48;
    }

    .main-content {
        min-height: calc(100vh - var(--header-height));
        flex-direction: column;
        overflow: visible;
    }

    #editor-container {
        width: 100% !important;
        min-height: 42vh;
        border-right: 0;
        border-bottom: 1px solid var(--color-border);
    }

    #resizer {
        display: none;
    }

    #preview {
        min-width: 0;
        padding: 32px 24px;
        overflow: visible;
    }

    #preview .rendered-content {
        max-width: none;
    }
}