:root {
    --bg-gradient-start: #b8ddf5;
    --bg-gradient-mid: #bce8d0;
    --bg-gradient-end: #ecc9dd;
    --card-bg: #ffffff;
    --text-primary: #1a252f;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --border-color: #a0aec0;
    --input-bg: #ffffff;
    --input-border: #8a9eb2;
    --button-primary: #1e88e5;
    --button-primary-hover: #1565c0;
    --button-primary-gradient: linear-gradient(135deg, #1e88e5 0%, #10b981 100%);
    --button-primary-gradient-hover: linear-gradient(135deg, #1976d2 0%, #0ea271 100%);
    --button-gradient: linear-gradient(120deg, #2f96bb 0%, #4fb8c9 60%, #7fd0df 100%);
    --button-gradient-hover: linear-gradient(120deg, #257c9b 0%, #3ea3bb 60%, #6ac4d8 100%);
    --button-warning: #e67e22;
    --button-warning-hover: #d35400;
    --progress-bg: #e2e8f0;
    --progress-fill: #00bcd4;
    --log-bg: #f7fafc;
    --info-bg: #dbeafe;
    --info-border: #60a5fa;
    --error-color: #e74c3c;
    --shadow: rgba(0, 0, 0, 0.12);
    --shadow-hover: rgba(0, 0, 0, 0.18);
    --focus-shadow: rgba(30, 136, 229, 0.15);
    --active-ring: rgba(30, 136, 229, 0.2);
    --font-monospace: 'Consolas', 'Monaco', 'Courier New', monospace;
}

[data-theme="dark"] {
    --bg-gradient-start: #0b1220;
    --bg-gradient-mid: #101a2f;
    --bg-gradient-end: #162846;
    --card-bg: #0f1b2e;
    --text-primary: #eaf2ff;
    --text-secondary: #b8c6db;
    --text-muted: #8fa2bf;
    --border-color: #26364f;
    --input-bg: #16243a;
    --input-border: #30445f;
    --button-primary: #60a5fa;
    --button-primary-hover: #3b82f6;
    --button-primary-gradient: linear-gradient(135deg, #60a5fa 0%, #3b82f6 100%);
    --button-primary-gradient-hover: linear-gradient(135deg, #3b82f6 0%, #60a5fa 100%);
    --button-gradient: linear-gradient(120deg, #60a5fa 0%, #3b82f6 60%, #2563eb 100%);
    --button-gradient-hover: linear-gradient(120deg, #93bbfd 0%, #60a5fa 60%, #3b82f6 100%);
    --button-warning: #e67e22;
    --button-warning-hover: #f39c12;
    --progress-bg: #18273f;
    --progress-fill: #27ae60;
    --log-bg: #16243a;
    --info-bg: #16243a;
    --info-border: #4f8dd6;
    --error-color: #e74c3c;
    --shadow: rgba(0, 0, 0, 0.3);
    --shadow-hover: rgba(0, 0, 0, 0.4);
    --focus-shadow: rgba(96, 165, 250, 0.25);
    --active-ring: rgba(96, 165, 250, 0.32);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;\n    font-size: 16px;
    line-height: 1.6;
    margin: 0;
    padding: 24px;
    background: linear-gradient(135deg, var(--bg-gradient-start) 0%, var(--bg-gradient-mid) 52%, var(--bg-gradient-end) 100%);
    min-height: 100vh;
    color: var(--text-primary);
    transition: background 0.3s ease, color 0.3s ease, margin-left 0.3s ease;
}

.app-card {
    max-width: 900px;
    margin: 0 auto;
    background: var(--card-bg);
    border-radius: 8px;
    padding: 32px;
    box-shadow: 0 2px 8px var(--shadow);
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

.title-brand-wrap {
    position: relative;
    overflow: hidden;
    padding-top: 30px;
}

.brand-watermark {
    position: absolute;
    top: 10px;
    left: 16px;
    font-size: clamp(14px, 2vw, 16px);
    font-weight: 700;
    letter-spacing: 0.3px;
    text-decoration: none;
    color: color-mix(in srgb, var(--button-primary) 72%, var(--text-primary));
    background: color-mix(in srgb, var(--button-primary) 12%, var(--card-bg));
    border: 1px solid color-mix(in srgb, var(--button-primary) 30%, transparent);
    border-radius: 999px;
    padding: 4px 10px;
    pointer-events: auto;
    user-select: none;
    z-index: 0;
    line-height: 1;
}

.title-brand-wrap > h1,
.title-brand-wrap > h2,
.title-brand-wrap > .subtitle,
.title-brand-wrap > p {
    position: relative;
    z-index: 1;
}

.brand-watermark:hover {
    color: color-mix(in srgb, var(--button-primary) 84%, var(--text-primary));
    background: color-mix(in srgb, var(--button-primary) 18%, var(--card-bg));
}

.nav-toggle {
    position: fixed;
    top: calc(10px + env(safe-area-inset-top));
    left: 14px;
    z-index: 1001;
    width: auto;
    height: auto;
    border: none;
    border-radius: 0;
    background: none;
    color: color-mix(in srgb, var(--text-primary) 90%, transparent);
    font-size: 36px;
    font-weight: 400;
    line-height: 1;
    padding: 0 4px;
    cursor: pointer;
    box-shadow: none;
    transition: color 0.2s ease, transform 0.2s ease;
}

.nav-toggle:hover {
    transform: translateY(-1px);
    color: var(--button-primary);
}

.side-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 228px;
    height: 100vh;
    padding: calc(74px + env(safe-area-inset-top)) 12px 14px;
    display: flex;
    flex-direction: column;
    gap: 9px;
    border-right: 1px solid color-mix(in srgb, var(--input-border) 72%, transparent);
    border-radius: 0 22px 22px 0;
    background:
        linear-gradient(165deg, color-mix(in srgb, var(--card-bg) 96%, white 4%) 0%, color-mix(in srgb, var(--card-bg) 86%, var(--button-primary) 14%) 100%);
    box-shadow: 0 14px 34px color-mix(in srgb, var(--shadow) 80%, transparent);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    z-index: 1000;
}

.side-nav.collapsed {
    transform: translateX(-110%);
}

body {
    margin-left: 228px;
    transition: margin-left 0.3s ease;
}

body.nav-collapsed {
    margin-left: 0;
}

.nav-tab {
    flex: 0 0 auto;
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 8px;
    text-decoration: none;
    padding: 11px 14px;
    border-radius: 11px;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    border: 1px solid color-mix(in srgb, var(--input-border) 62%, transparent);
    background: color-mix(in srgb, var(--input-bg) 66%, transparent);
    box-shadow: inset 0 1px 0 color-mix(in srgb, white 60%, transparent);
    transition: all 0.2s ease;
}

.nav-tab:hover {
    color: var(--text-primary);
    transform: translateX(2px);
    border-color: color-mix(in srgb, var(--button-primary) 58%, var(--input-border));
    background: color-mix(in srgb, var(--button-primary) 18%, var(--input-bg));
}

.nav-tab-active {
    color: #fff;
    border-color: color-mix(in srgb, var(--button-primary) 78%, white);
    background: var(--button-primary-gradient);
    box-shadow: 0 6px 14px color-mix(in srgb, var(--button-primary) 33%, transparent);
}

h2 {
    margin: 0 0 8px;
    text-align: center;
    font-size: 28px;
    font-weight: 600;
    color: var(--text-primary);
}

p {
    margin: 0 0 24px;
    font-size: 14px;
    text-align: center;
    color: var(--text-secondary);
}

label {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
}

button, input, select {
    display: block;
    width: 100%;
    padding: 12px 16px;
    margin: 12px 0;
    border: 1px solid var(--input-border);
    border-radius: 6px;
    font-family: inherit;
    font-size: 16px;
    background: var(--input-bg);
    color: var(--text-primary);
    transition: all 0.2s ease;
}

/* ===== shared button system: keep in sync with styles.css and blackmagic-utils/styles.css ===== */
button {
    border: 0;
    border-radius: 8px;
    padding: 12px 16px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    color: #fff;
    background: var(--button-gradient);
    transition: background 0.2s ease;
}

button:hover:not(:disabled) {
    color: #fff;
    background: var(--button-gradient-hover);
}

button:disabled {
    color: #fff;
    cursor: not-allowed;
    opacity: 0.5;
}

.detach-btn {
    display: none;
}

input[type=file] {
    padding: 10px;
    cursor: pointer;
}

input[type=file]::file-selector-button {
    padding: 8px 16px;
    margin-right: 16px;
    background: var(--button-gradient);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: 500;
    transition: background 0.2s ease;
}

input[type=file]::file-selector-button:hover {
    background: var(--button-gradient-hover);
}

input[type=text] {
    font-family: var(--font-monospace);
}

#fw-row {
    display: flex;
}

.tab-row {
    display: flex;
    gap: 8px;
    background: color-mix(in srgb, var(--progress-bg) 62%, transparent);
    border: 1px solid color-mix(in srgb, var(--input-border) 65%, transparent);
    padding: 6px;
    border-radius: 10px;
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
}

.fw-source-tab {
    margin: 0;
    padding: 10px 12px;
    border-radius: 8px;
    background: color-mix(in srgb, var(--card-bg) 45%, transparent);
    color: var(--text-secondary);
    border: 1px solid color-mix(in srgb, var(--input-border) 55%, transparent);
    box-shadow: none;
    font-size: 14px;
    font-weight: 600;
}

.fw-source-tab:hover:not(:disabled) {
    transform: none;
    box-shadow: none;
    background: color-mix(in srgb, var(--button-primary) 16%, var(--card-bg));
    border-color: color-mix(in srgb, var(--button-primary) 45%, var(--input-border));
}

.fw-source-tab.active {
    background: var(--button-gradient);
    color: #fff;
    border-color: color-mix(in srgb, var(--button-primary) 85%, white);
    box-shadow: 0 1px 4px var(--shadow);
}

.fw-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
    max-height: 280px;
    overflow-y: auto;
    padding-right: 4px;
    padding: 4px;
    border: 1px solid color-mix(in srgb, var(--input-border) 70%, transparent);
    border-radius: 10px;
    background: color-mix(in srgb, var(--progress-bg) 55%, transparent);
}

.fw-list::-webkit-scrollbar {
    width: 8px;
}

.fw-list::-webkit-scrollbar-track {
    background: var(--progress-bg);
    border-radius: 4px;
}

.fw-list::-webkit-scrollbar-thumb {
    background: var(--input-border);
    border-radius: 4px;
}

.fw-list::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

.fw-item {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
    text-align: left;
    margin: 0;
    background: linear-gradient(180deg, color-mix(in srgb, var(--input-bg) 72%, transparent) 0%, color-mix(in srgb, var(--input-bg) 88%, transparent) 100%);
    color: var(--text-primary);
    border: 1px solid color-mix(in srgb, var(--input-border) 62%, transparent);
    box-shadow: 0 1px 2px var(--shadow);
    padding: 11px 12px;
    border-radius: 10px;
    backdrop-filter: blur(5px);
    -webkit-backdrop-filter: blur(5px);
}

.fw-item-badge {
    position: absolute;
    top: 8px;
    right: 8px;
    padding: 2px 7px;
    border-radius: 999px;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.2px;
    color: #fff;
    background: color-mix(in srgb, var(--button-primary) 82%, transparent);
    border: 1px solid color-mix(in srgb, var(--button-primary) 90%, white);
}

.fw-item:hover:not(:disabled) {
    transform: none;
    box-shadow: 0 2px 6px var(--shadow-hover);
    border-color: color-mix(in srgb, var(--button-primary) 50%, var(--input-border));
    background: linear-gradient(180deg, color-mix(in srgb, var(--button-primary) 14%, var(--input-bg)) 0%, color-mix(in srgb, var(--button-primary) 8%, var(--input-bg)) 100%);
}

.fw-item.active {
    border-color: color-mix(in srgb, var(--button-primary) 78%, white);
    box-shadow: 0 0 0 2px var(--active-ring), 0 2px 8px var(--shadow);
    background: linear-gradient(180deg, color-mix(in srgb, var(--button-primary) 20%, var(--input-bg)) 0%, color-mix(in srgb, var(--button-primary) 12%, var(--input-bg)) 100%);
}

.fw-item-main {
    display: block;
    width: 100%;
    padding-right: 68px;
    font-size: 14px;
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.fw-item-meta {
    display: block;
    width: 100%;
    font-size: 12px;
    line-height: 1.3;
    color: var(--text-muted);
    font-family: var(--font-monospace);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.fw-empty {
    font-size: 13px;
    color: var(--text-muted);
    padding: 10px 12px;
    border: 1px dashed var(--input-border);
    border-radius: 8px;
}

.fw-toggle {
    margin-top: 10px;
    background: transparent;
    color: var(--button-primary);
    border: 1px solid var(--input-border);
    box-shadow: none;
}

.fw-toggle:hover:not(:disabled) {
    transform: none;
    box-shadow: none;
    border-color: var(--button-primary);
    background: color-mix(in srgb, var(--button-primary) 10%, var(--input-bg));
}

input:focus {
    outline: none;
    border-color: var(--button-primary);
    box-shadow: 0 0 0 3px var(--focus-shadow);
}

#p-erase, #p-write, #l {
    display: none;
}

.progress-wrap {
    margin: 12px 0;
}

.progress-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    margin: 0 0 6px;
}

#pe,
#p {
    height: 36px;
    background: var(--progress-bg);
    margin: 0;
    border-radius: 18px;
    overflow: hidden;
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.1);
}

#pe div,
#p div {
    height: 100%;
    background: var(--progress-fill);
    width: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    transition: width 0.3s ease;
    font-size: 14px;
    font-weight: 600;
    border-radius: 18px;
}

#l {
    font-family: var(--font-monospace);
    font-size: 13px;
    max-height: 220px;
    overflow-y: auto;
    background: var(--log-bg);
    padding: 16px;
    margin: 12px 0;
    border-radius: 6px;
    line-height: 1.6;
    border: 1px solid var(--border-color);
}

#l::-webkit-scrollbar {
    width: 8px;
}

#l::-webkit-scrollbar-track {
    background: var(--progress-bg);
    border-radius: 4px;
}

#l::-webkit-scrollbar-thumb {
    background: var(--input-border);
    border-radius: 4px;
}

#l::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

.e {
    color: var(--error-color);
    font-weight: 500;
}

#info {
    display: none;
    margin: 12px 0;
    padding: 12px 16px;
    border: 1px solid var(--info-border);
    border-radius: 6px;
    background: var(--info-bg);
    font-family: var(--font-monospace);
    font-size: 13px;
    line-height: 1.5;
    white-space: pre-wrap;
    word-break: break-word;
    color: var(--text-primary);
}

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

#theme-switcher {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--card-bg);
    border-radius: 24px;
    padding: 8px;
    box-shadow: 0 2px 8px var(--shadow);
    display: flex;
    gap: 8px;
    z-index: 1000;
    transition: background 0.3s ease, box-shadow 0.3s ease, opacity 0.2s ease;
}

#theme-switcher.scrolling {
    opacity: 0.6;
}

.theme-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.2s ease;
    padding: 0;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}

.theme-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 2px 8px var(--shadow-hover);
}

.theme-btn.active {
    border-color: var(--button-primary);
    box-shadow: 0 0 0 2px var(--active-ring);
}

.theme-btn[data-theme="light"] {
    background: linear-gradient(135deg, #c6e6fb 0%, #f5d9e8 100%);
    color: #333;
}

.theme-btn[data-theme="dark"] {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: #ffd966;
}

.theme-btn:not(.active) {
    border-color: color-mix(in srgb, var(--text) 30%, transparent);
}

@media (max-width: 600px) {
    body {
        padding: 16px;
        padding-top: calc(98px + env(safe-area-inset-top));
        margin-left: 0;
    }

    .app-card {
        padding: 24px;
    }

    .brand-watermark {
        top: 10px;
        left: 12px;
        font-size: 13px;
        padding: 3px 9px;
    }

    .title-brand-wrap {
        padding-top: 28px;
    }

    .nav-toggle {
        display: block;
        top: calc(12px + env(safe-area-inset-top));
    }

    .side-nav {
        width: min(82vw, 300px);
        max-width: none;
        border-radius: 0 18px 18px 0;
        box-shadow: 0 18px 36px color-mix(in srgb, var(--shadow-hover) 82%, transparent);
        transform: translateX(-100%);
    }

    .side-nav:not(.collapsed) {
        transform: translateX(0);
    }

    #theme-switcher {
        top: calc(10px + env(safe-area-inset-top));
        right: 10px;
        padding: 4px 6px;
        gap: 4px;
        border-radius: 16px;
        background: color-mix(in srgb, var(--card-bg) 68%, transparent);
        border: 1px solid color-mix(in srgb, var(--border-color) 70%, transparent);
        backdrop-filter: blur(8px);
        -webkit-backdrop-filter: blur(8px);
        box-shadow: 0 1px 6px var(--shadow);
    }

    .theme-btn {
        width: 30px;
        height: 30px;
        font-size: 13px;
        line-height: 1;
    }

    .theme-btn:hover {
        transform: none;
    }

    #fw-row {
        flex-direction: column;
        align-items: stretch !important;
    }

    .fw-list {
        grid-template-columns: 1fr;
    }

    .fw-source-tab {
        font-size: 13px;
        padding: 9px 10px;
    }
}