:root {
    --color-bg: #1e1e1e;
    --color-text: #cfcfcf;
    --color-text-muted: #888888;
    --color-primary: #4f97d7;
    --color-primary-hover: #6ca0f6;
    --color-border: #333333;
    --color-error: #ff5c57;
    --color-success: #5af78e;
    --color-warning: #f3f99d;
    --font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    --font-size-base: 16px;
    --font-size-small: 14px;
    --spacing-base: 16px;
    --spacing-small: 8px;
    --border-radius: 4px;
}

/* prefer a light mode */
@media (prefers-color-scheme: light) {
    :root {
        --color-bg: #ffffff;
        --color-text: #333333;
        --color-text-muted: #777777;
        --color-primary: #007acc;
        --color-primary-hover: #005f99;
        --color-border: #dddddd;
        --color-error: #d32f2f;
        --color-success: #388e3c;
        --color-warning: #fbc02d;
    }
}

/* Attributes */
[hidden] {
    display: none !important;
}

[full-width] {
    width: 100%;
}

[full-height] {
    height: 100%;
}

[overlay] {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 999;
}

[modal] {
    z-index: 1000;
}

/**
 * App Element Styles
 */
html, body {
    height: 100%;
    width: 100%;
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background-color: var(--color-bg);
    color: var(--color-text);
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    overflow: hidden;
    height: 100%;
}

header {
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-base);
    height: 30px;
    z-index: 120;
}

main {
    padding: var(--spacing-base);
    height: calc(100% - 50px);
    overflow: auto;
    z-index: 110;
}

footer {
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-base);
    height: 20px;
    text-align: center;
    font-size: var(--font-size-small);
    z-index: 120;
}

nav {
    background-color: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: 0;
    margin: 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    align-items: center;
    gap: 0;
}

nav li {
    margin: 0;
    padding: 0;
}

nav a {
    display: block;
    padding: var(--spacing-base) calc(var(--spacing-base) * 1.5);
    color: var(--color-text);
    text-decoration: none;
    font-weight: 500;
    transition: background-color 0.2s ease, color 0.2s ease;
    border-bottom: 3px solid transparent;
    white-space: nowrap;
}

nav a:hover {
    background-color: rgba(79, 151, 215, 0.1);
    color: var(--color-primary);
}

nav a:active,
nav a.active {
    color: var(--color-primary);
    border-bottom-color: var(--color-primary);
}

/* Main content view with responsive side margins */
#view {
    max-width: 100%;
    margin: 0 auto;
}

@media (min-width: 1920px) {
    #view {
        max-width: 90%;
        margin: 0 5%;
    }
}

.signin-container {
    max-width: 400px;
    margin: 40px auto;
    padding: var(--spacing-base);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    background-color: var(--color-bg);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/**
 * Positioning and Layout
 */
.left {
    text-align: left;
}

.right {
    text-align: right;
}

.center {
    text-align: center;
}

/* Action / Upload panel styles */
.action-panel {
    display: flex;
    gap: var(--spacing-base);
    align-items: flex-start;
    flex-wrap: wrap;
    margin-top: calc(var(--spacing-base) * 1.25);
}

.upload-panel {
    flex: 1 1 420px;
    min-width: 260px;
    display: flex;
    gap: 12px;
    align-items: center;
    padding: calc(var(--spacing-small) * 1.5) var(--spacing-base);
    border-radius: calc(var(--border-radius) * 1.5);
    border: 1px dashed var(--color-border);
    background-color: color-mix(in srgb, var(--color-bg) 86%, #ffffff 14%);
    box-shadow: 0 6px 18px rgba(0, 0, 0, 0.05);
    transition: box-shadow 0.18s ease, border-color 0.18s ease;
    cursor: pointer;
}

.upload-panel:focus,
.upload-panel:hover {
    box-shadow: 0 18px 36px rgba(0, 0, 0, 0.12);
    border-color: color-mix(
        in srgb,
        var(--color-primary) 25%,
        var(--color-border)
    );
}

.upload-panel.dragover {
    border-color: var(--color-primary);
    background-color: color-mix(
        in srgb,
        var(--color-bg) 78%,
        var(--color-primary) 6%
    );
}

.upload-icon {
    width: 48px;
    height: 48px;
    flex: 0 0 48px;
}

.upload-meta {
    flex: 1 1 auto;
    min-width: 0;
}

.upload-select {
    width: 100%;
    margin-top: 12px;
}

.upload-select label {
    display: block;
    margin-bottom: 6px;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--color-text);
}

.select-wrapper {
    position: relative;
}

.select-wrapper select {
    width: 100%;
    padding: 12px 44px 12px 14px;
    border-radius: calc(var(--border-radius) * 1.5);
    border: 1px solid color-mix(in srgb, var(--color-border) 90%, var(--color-primary) 10%);
    background-color: color-mix(in srgb, var(--color-bg) 92%, #ffffff 8%);
    color: var(--color-text);
    font-size: 0.95rem;
    appearance: none;
    background-image: url("../icons/arrow-down.svg");
    background-repeat: no-repeat;
    background-size: 18px;
    background-position: right 14px center;
    transition: border-color 0.18s ease, box-shadow 0.18s ease;
}

.select-wrapper select:hover {
    border-color: color-mix(
        in srgb,
        var(--color-primary) 30%,
        var(--color-border)
    );
}

.select-wrapper select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(79, 151, 215, 0.2);
}

.upload-title {
    margin: 0 0 6px 0;
    font-size: 1rem;
    font-weight: 700;
    color: var(--color-text);
}

.upload-sub {
    margin: 0;
    color: var(--color-text-muted);
    font-size: 0.95rem;
}

.upload-actions {
    margin-top: 10px;
    display: flex;
    gap: 8px;
    align-items: center;
}

/* labels styled as buttons for file chooser */
.upload-actions label.btn-file {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 14px;
    border-radius: var(--border-radius);
    background-color: var(--color-primary);
    color: #fff;
    cursor: pointer;
    user-select: none;
}

.upload-actions .btn-outline {
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text);
}

.file-input {
    display: none;
}

.progress {
    height: 8px;
    background: var(--color-border);
    border-radius: 999px;
    overflow: hidden;
    margin-top: 10px;
}

.progress > i {
    display: block;
    height: 100%;
    width: 0%;
    background: linear-gradient(
        90deg,
        var(--color-primary),
        var(--color-primary-hover)
    );
    transition: width 0.35s ease;
}

.action-help {
    width: 220px;
    min-width: 160px;
    font-size: 0.95rem;
    color: var(--color-text-muted);
}

@media (max-width: 640px) {
    .action-help {
        width: 100%;
    }
    .upload-panel {
        flex: 1 1 100%;
    }
}