:root {
    --bg: #faf9f7;
    --bg-secondary: #f0eee9;
    --text: #2c2c2c;
    --text-secondary: #8a8578;
    --accent: #4a7a3f;
    --accent-hover: #5a8f4e;
    --border: #d8d4cc;
    --error: #c45c4a;
    --success: #4a7a3f;
    --warm-glow: #c4a24e;
    --radius: 16px;
    --font: "Georgia", "Times New Roman", serif;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #1a1b17;
        --bg-secondary: #242421;
        --text: #e0ded8;
        --text-secondary: #8a8578;
        --accent: #8fa37a;
        --accent-hover: #a0b48c;
        --border: #3a3a36;
        --error: #d4756a;
        --success: #8fa37a;
        --warm-glow: #c4a24e;
    }
}

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

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    padding: 4rem 1.5rem 3rem;
}

.container {
    width: 100%;
    max-width: 480px;
}

header {
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

h1 {
    font-size: 1.75rem;
    font-weight: 400;
    letter-spacing: 0.15em;
    text-transform: lowercase;
}

.subtitle {
    color: var(--text-secondary);
    margin-top: 0.5rem;
    font-size: 0.9rem;
    font-style: italic;
}

.lang-toggle {
    position: absolute;
    top: 0;
    right: 0;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.8rem;
    letter-spacing: 0.05em;
    transition: color 0.3s;
}

.lang-toggle:hover {
    color: var(--text);
}

/* Upload zone */
.upload-zone {
    border: 1.5px dashed var(--border);
    border-radius: var(--radius);
    padding: 2.5rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: border-color 0.4s ease, background 0.4s ease;
    margin-bottom: 2rem;
}

.upload-zone:hover,
.upload-zone.drag-over {
    border-color: var(--accent);
    background: var(--bg-secondary);
}

.upload-label {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
}

.upload-icon {
    color: var(--text-secondary);
    transition: color 0.3s;
    opacity: 0.7;
}

.upload-zone:hover .upload-icon {
    color: var(--accent);
    opacity: 1;
}

.hint {
    font-size: 0.78rem;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
}

#file-input {
    display: none;
}

.file-name {
    margin-top: 0.75rem;
    font-weight: 400;
    color: var(--accent);
    word-break: break-all;
    font-size: 0.9rem;
}

/* Form controls */
.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 0.4rem;
    letter-spacing: 0.03em;
}

select,
input[type="number"] {
    width: 100%;
    padding: 0.6rem 0.75rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--bg);
    color: var(--text);
    font-family: var(--font);
    font-size: 0.95rem;
    transition: border-color 0.3s;
    appearance: auto;
}

select:focus,
input[type="number"]:focus {
    outline: none;
    border-color: var(--accent);
}

input[type="range"] {
    width: 100%;
    accent-color: var(--accent);
    margin-top: 0.25rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-secondary);
    letter-spacing: 0.03em;
}

.checkbox-label input {
    accent-color: var(--accent);
    width: 1rem;
    height: 1rem;
}

button[type="submit"] {
    width: 100%;
    padding: 0.8rem;
    background: var(--accent);
    color: var(--bg);
    border: none;
    border-radius: 8px;
    font-family: var(--font);
    font-size: 0.95rem;
    font-weight: 400;
    letter-spacing: 0.1em;
    cursor: pointer;
    transition: background 0.3s ease, opacity 0.3s ease;
    margin-top: 1rem;
}

button[type="submit"]:hover {
    background: var(--accent-hover);
}

button[type="submit"]:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

/* Status */
.status-text {
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-style: italic;
}

.progress-bar {
    height: 8px;
    background: var(--border);
    border-radius: 4px;
    overflow: hidden;
    margin-top: 0.75rem;
}

#progress-fill {
    height: 100%;
    background: var(--accent);
    border-radius: 4px;
    width: 0%;
    transition: width 0.5s ease;
}

/* Results */
#results {
    text-align: center;
    margin-top: 1.5rem;
}

#download-links {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
    margin-bottom: 1rem;
}

#download-links a {
    display: block;
    padding: 0.75rem;
    background: transparent;
    color: var(--accent);
    text-decoration: none;
    border: 1.5px solid var(--accent);
    border-radius: 8px;
    letter-spacing: 0.05em;
    font-size: 0.9rem;
    transition: background 0.3s, color 0.3s;
}

#download-links a:hover {
    background: var(--accent);
    color: var(--bg);
}

/* Error */
.error-box {
    background: transparent;
    color: var(--error);
    border: 1.5px solid var(--error);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    text-align: center;
    font-size: 0.9rem;
    margin-top: 1.5rem;
}

.hidden {
    display: none;
}

#hillshade-options:not(.hidden) {
    padding: 0.5rem 0;
}

/* Divider */
#hillshade-toggle-group {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
}

footer {
    text-align: center;
    margin-top: 3rem;
}

.donate-btn {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.8rem;
    letter-spacing: 0.05em;
    transition: color 0.3s;
}

.donate-btn:hover {
    color: var(--text);
}