/* General styles */
:root {
    --tg-bg: var(--tg-theme-bg-color, #f4f7fa);
    --tg-text: var(--tg-theme-text-color, #1a1a1a);
    --tg-button: var(--tg-theme-button-color, #007aff);
    --tg-button-text: var(--tg-theme-button-text-color, #ffffff);
    --tg-hint: var(--tg-theme-hint-color, #999999);
    --tg-secondary-bg: var(--tg-theme-secondary-bg-color, #e9ecef);

    --border-radius-m: 8px;
    --border-radius-l: 12px;
    --transition-speed: 0.2s;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--tg-bg);
    color: var(--tg-text);
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 15px;
    box-sizing: border-box;
}

.container {
    width: 100%;
    max-width: 420px;
    display: flex;
    flex-direction: column;
    gap: 25px;
}

/* Header */
.header {
    text-align: center;
}

.header h1 {
    font-size: 24px;
    font-weight: 600;
    margin: 0 0 5px 0;
}

.header p {
    font-size: 15px;
    color: var(--tg-hint);
    margin: 0;
}

/* Form */
#uploadForm {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* File Upload */
.file-upload-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.file-upload-label {
    width: 100%;
    padding: 30px 15px;
    border: 2px dashed var(--tg-hint);
    border-radius: var(--border-radius-l);
    background-color: var(--tg-secondary-bg);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.file-upload-label:hover {
    background-color: rgba(0,0,0,0.05);
    border-color: var(--tg-button);
}

.file-upload-icon svg {
    width: 32px;
    height: 32px;
    color: var(--tg-hint);
    margin-bottom: 10px;
    transition: color var(--transition-speed);
}

.file-upload-label:hover .file-upload-icon svg {
    color: var(--tg-button);
}

.file-upload-text {
    font-size: 16px;
    font-weight: 500;
}

.file-name {
    font-size: 14px;
    color: var(--tg-hint);
    font-weight: 500;
    min-height: 20px; /* Reserve space */
}

/* Section Title (used for format selector) */
.section-title {
    font-size: 15px;
    font-weight: 500;
    color: var(--tg-text);
    text-align: center;
    margin: 0 0 10px 0;
}

/* Format Selector */
.format-selector {
    display: flex;
    background-color: var(--tg-secondary-bg);
    border-radius: var(--border-radius-m);
    padding: 5px;
}

.format-selector label {
    flex: 1;
    position: relative;
    text-align: center;
}

.format-selector input[type="radio"] {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.format-selector span {
    display: block;
    padding: 10px;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

.format-selector input[type="radio"]:checked + span {
    background-color: var(--tg-button);
    color: var(--tg-button-text);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

/* Submit Button */
#submitButton {
    padding: 15px;
    font-size: 16px;
    font-weight: 600;
    background-color: var(--tg-button);
    color: var(--tg-button-text);
    border: none;
    border-radius: var(--border-radius-l);
    cursor: pointer;
    transition: transform var(--transition-speed), opacity var(--transition-speed);
}

#submitButton:hover {
    transform: scale(1.02);
}

#submitButton:active {
    transform: scale(0.98);
    opacity: 0.9;
}

#submitButton:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}


/* Log & Download Link */
.log-container, .download-container {
    text-align: center;
    font-size: 15px;
    font-weight: 500;
}

#downloadLink {
    display: inline-block;
    padding: 12px 25px;
    background-color: var(--tg-secondary-bg);
    color: var(--tg-button);
    border-radius: var(--border-radius-l);
    text-decoration: none;
    font-weight: 600;
    transition: transform var(--transition-speed);
}

#downloadLink:hover {
    transform: scale(1.05);
}