/* Simple Image Tool - Global Styles */

:root {
    --bg-color: #f4f7f9;
    --text-color: #1a1a1a;
    --card-bg-color: #ffffff;
    --primary-color: #007bff;
    --primary-hover-color: #0056b3;
    --secondary-color: #6c757d;
    --button-text-color: #ffffff;
    --border-color: #dee2e6;
    --shadow-color: rgba(0, 0, 0, 0.05);
    --active-button-bg: #e9ecef;
    --active-button-color: #1a1a1a;
    --modal-overlay-color: rgba(0, 0, 0, 0.4);

    /* Translucent Gradients */
    --gradient-primary: linear-gradient(135deg, rgba(0, 123, 255, 0.85), rgba(0, 86, 179, 0.85));
    --gradient-primary-hover: linear-gradient(135deg, rgba(0, 123, 255, 0.95), rgba(0, 86, 179, 0.95));
    --gradient-success: linear-gradient(135deg, rgba(40, 167, 69, 0.85), rgba(33, 136, 56, 0.85));
}

html.dark-mode {
    --bg-color: #1a1c1e;
    --text-color: #e3e3e3;
    --card-bg-color: #25282c;
    --primary-color: #3b82f6;
    --primary-hover-color: #2563eb;
    --secondary-color: #a0a0a0;
    --border-color: #374151;
    --shadow-color: rgba(0, 0, 0, 0.2);
    --active-button-bg: #374151;
    --active-button-color: #ffffff;
    --modal-overlay-color: rgba(0, 0, 0, 0.6);

    --gradient-primary: linear-gradient(135deg, rgba(59, 130, 246, 0.8), rgba(37, 99, 235, 0.8));
    --gradient-primary-hover: linear-gradient(135deg, rgba(59, 130, 246, 0.9), rgba(37, 99, 235, 0.9));
}

* { box-sizing: border-box; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0 1em 2em 1em;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: background-color 0.3s, color 0.3s;
    min-height: 100vh;
}

/* Header & Navigation Buttons */
header {
    width: 100%;
    max-width: 1000px;
    display: flex;
    justify-content: flex-end;
    align-items: center;
    padding: 1.5em 0;
    gap: 0.8em;
}

.header-btn {
    background-color: var(--card-bg-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    padding: 0.5em 1em;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.85em;
    font-weight: 500;
    transition: all 0.2s;
    width: auto;
}
.header-btn:hover {
    background-color: var(--active-button-bg);
    border-color: var(--primary-color);
}

/* Modal Core Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0; top: 0;
    width: 100%; height: 100%;
    align-items: center;
    justify-content: center;
}
.modal.open { display: flex; }
.modal-overlay {
    position: absolute; width: 100%; height: 100%;
    background-color: var(--modal-overlay-color);
    backdrop-filter: blur(2px);
}
.modal-content {
    position: relative;
    background-color: var(--card-bg-color);
    padding: 2.5em;
    border-radius: 16px;
    width: 90%;
    max-width: 420px;
    box-shadow: 0 20px 50px rgba(0,0,0,0.3);
    animation: modalFadeIn 0.3s ease-out;
}
@keyframes modalFadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.modal-content h2 { margin: 0 0 1.2em 0; font-size: 1.4em; }

.modal-options { display: flex; flex-direction: column; gap: 0.6em; }
.modal-options button {
    width: 100%;
    padding: 1em;
    border: 1px solid var(--border-color);
    background-color: var(--bg-color);
    color: var(--text-color);
    border-radius: 10px;
    text-align: left;
    font-size: 1em;
    cursor: pointer;
    transition: all 0.2s;
}
.modal-options button:hover { background-color: var(--active-button-bg); }
.modal-options button.active {
    background: var(--gradient-primary);
    color: var(--button-text-color);
    border-color: transparent;
}

.close-modal-btn {
    position: absolute; top: 1em; right: 1em;
    background: none; border: none; font-size: 1.8em;
    cursor: pointer; color: var(--secondary-color);
    line-height: 1; padding: 4px;
    transition: color 0.2s;
}
.close-modal-btn:hover { color: var(--primary-color); }

/* Common Tool Layout */
#main-container {
    width: 100%;
    max-width: 1000px;
    background-color: var(--card-bg-color);
    padding: 2.5em;
    border-radius: 16px;
    box-shadow: 0 10px 30px var(--shadow-color);
}

/* Language-specific Tweaks */
:lang(ja) .header-btn { font-size: 0.8em; }