:root {
    --surface: #f9f9f9;
    --surface-low: #f2f4f4;
    --surface-high: #e4e9ea;
    --surface-card: rgba(255, 255, 255, 0.82);
    --glass: rgba(221, 228, 229, 0.74);
    --ink: #2d3435;
    --muted: #5a6061;
    --outline: rgba(117, 124, 125, 0.18);
    --primary: #5d5e61;
    --primary-dim: #515255;
    --tertiary: #6a5e43;
    --success: #2d8b57;
    --warning: #ab7c20;
    --error: #9f403d;
    --shadow: 0 24px 48px -16px rgba(45, 52, 53, 0.14);
    --shadow-soft: 0 18px 36px -20px rgba(45, 52, 53, 0.12);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Manrope", sans-serif;
    background:
        radial-gradient(circle at top right, rgba(254, 236, 202, 0.46), transparent 28%),
        linear-gradient(145deg, rgba(255,255,255,0.7), rgba(242,244,244,0.88)),
        var(--surface);
    color: var(--ink);
    min-height: 100vh;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    background:
        linear-gradient(112deg, rgba(255,255,255,0.06) 0%, transparent 42%, rgba(255,255,255,0.04) 100%),
        repeating-linear-gradient(135deg, rgba(255,255,255,0.08) 0 12px, rgba(173,179,180,0.05) 12px 30px, transparent 30px 120px);
    z-index: -1;
}

a {
    color: inherit;
}

.material-symbols-outlined {
    font-family: "Material Symbols Outlined";
    font-weight: normal;
    font-style: normal;
    font-size: 24px;
    display: inline-block;
    line-height: 1;
    letter-spacing: normal;
    text-transform: none;
    white-space: nowrap;
    word-wrap: normal;
    direction: ltr;
    font-variation-settings: "FILL" 0, "wght" 250, "GRAD" 0, "opsz" 24;
}

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

.header {
    position: sticky;
    top: 0;
    z-index: 30;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    padding: 22px 34px;
    background: rgba(249, 249, 249, 0.76);
    backdrop-filter: blur(22px);
    border-bottom: 1px solid var(--outline);
}

.header__brand {
    display: grid;
    gap: 8px;
}

.header__eyebrow,
.section-label,
.label {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.28em;
    text-transform: uppercase;
    color: var(--tertiary);
}

.title-3d {
    font-family: "Noto Serif", serif;
    font-size: clamp(2.1rem, 4vw, 3.5rem);
    font-weight: 400;
    letter-spacing: -0.05em;
    text-shadow: 0 4px 10px rgba(45, 52, 53, 0.08);
}

.header__lead {
    color: var(--muted);
    font-family: "Noto Serif", serif;
    font-style: italic;
    max-width: 620px;
    line-height: 1.8;
}

.header__actions {
    display: flex;
    align-items: center;
    gap: 14px;
    flex-wrap: wrap;
    justify-content: flex-end;
}

.header-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 16px;
    text-decoration: none;
    background: rgba(255,255,255,0.82);
    border: 1px solid var(--outline);
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    transition: transform 0.2s ease, background 0.2s ease;
}

.header-link:hover,
.btn:hover,
.btn-browse:hover,
.viewer-tab:hover,
.tab:hover,
.size-btn:hover,
.btn-rotate:hover {
    transform: translateY(-1px);
}

.header__status {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 16px;
    background: rgba(255,255,255,0.82);
    border: 1px solid var(--outline);
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 999px;
    background: var(--warning);
    box-shadow: 0 0 10px rgba(171, 124, 32, 0.35);
    animation: pulse 1.6s infinite;
}

.status-dot.connected {
    background: var(--success);
    animation: none;
    box-shadow: 0 0 12px rgba(45, 139, 87, 0.35);
}

.status-dot.error {
    background: var(--error);
    animation: none;
}

.status-text {
    font-size: 12px;
    font-weight: 600;
    color: var(--muted);
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.45; }
}

.workspace {
    display: grid;
    grid-template-columns: 92px 1fr;
    min-height: calc(100vh - 153px);
}

.nav-rail {
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding: 22px 10px;
    background: linear-gradient(180deg, rgba(255,255,255,0.56), rgba(211, 219, 221, 0.78));
    backdrop-filter: blur(20px);
    border-right: 1px solid var(--outline);
}

.rail-link {
    min-height: 78px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    text-decoration: none;
    color: var(--muted);
    border: 1px solid transparent;
    transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.rail-link span:last-child {
    font-size: 9px;
    font-weight: 700;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    text-align: center;
}

.rail-link:hover,
.rail-link.is-active {
    background: rgba(255,255,255,0.5);
    border-color: rgba(117,124,125,0.1);
    color: var(--ink);
}

.main {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 360px;
    gap: 22px;
    padding: 22px 24px 28px 22px;
}

.center-zone {
    display: grid;
    gap: 22px;
    align-content: start;
}

.intro-card,
.stage-card,
.panel,
.result-info,
.control-group,
.viewer,
.header-link,
.header__status {
    box-shadow: var(--shadow);
}

.intro-card,
.stage-card,
.panel,
.control-group,
.result-info,
.viewer,
.drop-zone {
    background: var(--surface-card);
    border: 1px solid var(--outline);
    backdrop-filter: blur(18px);
}

.intro-card {
    padding: 28px;
}

.intro-grid {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(280px, 0.55fr);
    gap: 26px;
    align-items: end;
    margin-top: 14px;
}

.intro-grid h2 {
    font-family: "Noto Serif", serif;
    font-size: clamp(2rem, 4vw, 3.35rem);
    font-weight: 400;
    letter-spacing: -0.05em;
    line-height: 0.97;
    margin-bottom: 16px;
    text-shadow: 0 4px 10px rgba(45, 52, 53, 0.08);
}

.intro-grid p {
    color: var(--muted);
    line-height: 1.9;
    max-width: 680px;
}

.intro-metrics {
    display: grid;
    gap: 12px;
}

.metric-card {
    padding: 16px;
    background: rgba(255,255,255,0.58);
    border: 1px solid rgba(117,124,125,0.12);
}

.metric-card strong {
    display: block;
    font-family: "Noto Serif", serif;
    font-size: 1.6rem;
    font-weight: 400;
    letter-spacing: -0.05em;
    margin-bottom: 6px;
}

.metric-card span {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--muted);
}

.stage-card {
    padding: 18px;
}

.drop-zone {
    width: 100%;
    min-height: 560px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: border-color 0.25s ease, background 0.25s ease, transform 0.25s ease;
    background:
        radial-gradient(circle at top right, rgba(254,236,202,0.24), transparent 28%),
        linear-gradient(145deg, rgba(255,255,255,0.74), rgba(242,244,244,0.88));
}

.drop-zone:hover,
.drop-zone.dragover {
    border-color: rgba(106, 94, 67, 0.34);
    background:
        radial-gradient(circle at top right, rgba(254,236,202,0.32), transparent 28%),
        linear-gradient(145deg, rgba(255,255,255,0.86), rgba(228,233,234,0.9));
}

.drop-zone__content {
    display: grid;
    justify-items: center;
    gap: 16px;
    text-align: center;
}

.drop-zone__icon {
    width: 94px;
    height: 94px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary) 0%, #d3d4d6 100%);
    color: #f7f7fa;
    box-shadow: var(--shadow-soft);
}

.drop-zone__icon .material-symbols-outlined {
    font-size: 44px;
}

.drop-zone__text {
    font-family: "Noto Serif", serif;
    font-size: 2rem;
    font-style: italic;
    letter-spacing: -0.04em;
}

.drop-zone__or,
.file-name,
.viewer__info,
.preview-info,
.field-hint {
    color: var(--muted);
}

.drop-zone__or {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.26em;
    text-transform: uppercase;
}

.btn-browse,
.btn,
.viewer-tab,
.tab,
.size-btn,
.btn-rotate {
    border: 1px solid var(--outline);
    background: rgba(255,255,255,0.82);
    color: var(--ink);
    cursor: pointer;
    transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.btn-browse,
.btn {
    padding: 15px 18px;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
}

.btn--primary,
.viewer-tab.active,
.tab.active,
.size-btn.active {
    background: linear-gradient(135deg, var(--primary) 0%, #d3d4d6 100%);
    color: #f7f7fa;
    border-color: transparent;
}

.file-name {
    padding: 14px 2px 0;
    font-size: 13px;
    min-height: 32px;
}

.viewer {
    overflow: hidden;
}

.viewer.size-sm .preview-image { max-height: 36vh; }
.viewer.size-md .preview-image { max-height: 62vh; }
.viewer.size-lg .preview-image { max-height: 76vh; }

.viewer.size-xl {
    position: fixed;
    inset: 0;
    z-index: 120;
    border-radius: 0;
}

.viewer__tabs,
.viewer__info,
.panel__header,
.footer {
    background: rgba(255,255,255,0.62);
}

.viewer__tabs {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 14px;
    border-bottom: 1px solid var(--outline);
}

.viewer-tab,
.tab {
    padding: 12px 16px;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.16em;
    text-transform: uppercase;
}

.viewer__size-selector {
    margin-left: auto;
    display: flex;
    gap: 6px;
}

.size-btn,
.btn-rotate {
    width: 40px;
    height: 40px;
    font-size: 12px;
    font-weight: 700;
}

.viewer__canvas {
    position: relative;
    min-height: 620px;
    padding: 18px;
    background:
        radial-gradient(circle at top right, rgba(254,236,202,0.18), transparent 26%),
        linear-gradient(145deg, rgba(242,244,244,0.82), rgba(228,233,234,0.92));
}

.image-container {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 560px;
    overflow: hidden;
    background: rgba(255,255,255,0.68);
    border: 1px solid rgba(117,124,125,0.1);
}

.preview-image {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    box-shadow: 0 24px 48px -24px rgba(45, 52, 53, 0.28);
}

.compare-slider {
    position: absolute;
    inset: 0 auto 0 50%;
    width: 2px;
    background: rgba(255,255,255,0.94);
    box-shadow: 0 0 16px rgba(255,255,255,0.4);
    cursor: ew-resize;
}

.compare-slider__handle {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 44px;
    height: 44px;
    transform: translate(-50%, -50%);
    background: rgba(255,255,255,0.94);
    border: 1px solid rgba(117,124,125,0.12);
}

.progress-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(12,15,15,0.42);
}

.progress-card {
    display: grid;
    justify-items: center;
    gap: 14px;
    padding: 28px 32px;
    background: rgba(255,255,255,0.92);
    border: 1px solid rgba(117,124,125,0.12);
    box-shadow: var(--shadow);
}

.spinner {
    width: 34px;
    height: 34px;
    border: 2px solid rgba(117,124,125,0.2);
    border-top-color: var(--primary);
    border-radius: 999px;
    animation: spin 1s linear infinite;
}

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

.viewer__info {
    padding: 14px 18px;
    border-top: 1px solid var(--outline);
    font-size: 13px;
}

.panel {
    display: grid;
    align-content: start;
    gap: 16px;
    padding: 18px;
    overflow: auto;
}

.panel__header {
    padding: 18px;
    border: 1px solid var(--outline);
}

.panel__title {
    font-family: "Noto Serif", serif;
    font-size: 1.65rem;
    font-weight: 400;
    letter-spacing: -0.04em;
    margin-bottom: 8px;
}

.panel__subtitle {
    color: var(--muted);
    line-height: 1.8;
    font-size: 14px;
}

.control-group,
.result-info {
    padding: 18px;
    display: grid;
    gap: 14px;
}

.tabs {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
}

.select,
.slider,
.color-picker {
    width: 100%;
}

.select,
.rotation-value {
    padding: 14px 12px;
    border: 1px solid rgba(117,124,125,0.16);
    background: rgba(255,255,255,0.82);
    color: var(--ink);
    font-family: "Manrope", sans-serif;
}

.slider-group {
    display: grid;
    gap: 8px;
}

.slider-group label,
.checkbox,
.info-row,
.rotation-btns {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.slider {
    appearance: none;
    height: 2px;
    background: rgba(117,124,125,0.32);
}

.slider::-webkit-slider-thumb {
    appearance: none;
    width: 14px;
    height: 14px;
    background: var(--primary);
    border: 0;
}

.field-hint,
.preview-info {
    font-size: 12px;
    line-height: 1.6;
}

.checkbox input {
    width: 18px;
    height: 18px;
}

.color-group {
    display: grid;
    gap: 8px;
}

.color-picker {
    height: 48px;
    border: 1px solid rgba(117,124,125,0.16);
    background: rgba(255,255,255,0.82);
    padding: 4px;
}

.rotation-btns {
    justify-content: center;
}

.rotation-value {
    min-width: 86px;
    text-align: center;
    font-family: "Noto Serif", serif;
}

.actions {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.info-row {
    font-size: 13px;
    color: var(--muted);
}

.info-row span:last-child {
    color: var(--ink);
    font-weight: 600;
}

.footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 16px 24px;
    border-top: 1px solid var(--outline);
    font-size: 12px;
    color: var(--muted);
}

.footer a {
    text-decoration: none;
    font-weight: 700;
    letter-spacing: 0.16em;
    text-transform: uppercase;
}

@media (max-width: 1180px) {
    .main {
        grid-template-columns: 1fr 320px;
    }

    .intro-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 980px) {
    .workspace {
        grid-template-columns: 1fr;
    }

    .nav-rail {
        display: none;
    }

    .main {
        grid-template-columns: 1fr;
    }

    .panel {
        order: 2;
    }
}

@media (max-width: 720px) {
    .header {
        flex-direction: column;
        align-items: flex-start;
        padding: 18px;
    }

    .header__actions {
        width: 100%;
        justify-content: space-between;
    }

    .main {
        padding: 16px;
    }

    .intro-card,
    .stage-card,
    .panel {
        padding: 16px;
    }

    .drop-zone {
        min-height: 360px;
    }

    .viewer__tabs {
        flex-wrap: wrap;
    }

    .viewer__size-selector {
        width: 100%;
        margin-left: 0;
    }

    .viewer__canvas,
    .image-container {
        min-height: 320px;
    }

    .actions {
        grid-template-columns: 1fr;
    }

    .footer {
        flex-direction: column;
        align-items: flex-start;
    }
}